Why does my circular saw shaft spin and blade does not? So i was cutting wood and noticed the shaft was slipping on the blade. So i took off the blade and put it back on making sure it was tight and it stalled so i loosened the bolt a little bit it stalled less then i loosened it more and it started slipping again i don't know what it could be.

(I have a craftsman 5 1/2 inch 4/5 hp circular saw #H9179 and it is one of the older corded models)

Thank You

Why does my circular saw shaft spin and blade does not?

Because you loosened the nut or bolt holding the blade to the shaft.

  it stalled so [I] loosened the bolt a little

It would probably be more appropriate to  ...

sharpen the blade or
cut more slowly or
make sure the kerf isn't closing onto the blade due to ...

poorly supported workpiece
stresses in wood


How to remove faucet with no screw? NEW EDIT #2, SEE BELOW:

Kitchen sink drips from the tap, stops when I turn off hot water shut-off underneath, so I assume the problem is the hot water faucet. I think I know how to repair a faucet with a screw (unscrew to access cartridge and replace it), but when I pried the "H" cap off this one and the metal disk under the "H", there was no screw underneath...just a hole (see photos).

There appears to be nothing obvious inside to unscrew. So, how do I proceed to fix this faucet?

Thanks!

EDIT #2: I give up on removing it from above--I am going to try to remove this from underneath the sink. I'm attaching new photos of what that looks like, and asking for guidance. As you can see, this has been dripping down and rusted out the washer. Do I definitely need a basin wrench to do this, or can I use a socket wrench? What happens when I get this disconnected from underneath?

Whole sink underneath, showing faulty hot water on right:

Hot water underneath, close-up:

To remove the trim - aka faucet handle and rosette, unthread the rosette, which will remove BOTH the rosette and the handle/lever at the same time.
Many Kohler, grohe and price pfister faucets’ handle assemblies install this way.


Proper installation of a supply line escutcheon I have built 4 houses and finished 3 rehabs including the plumbing without figuring out how to properly install the supply line escutcheons.
I think sticking it to the wall with putty is tacky, no pun intended, and part of the pipe between the escutcheon/flange and the cutoff valve still show.
How do you install the escutcheon snugly and avoid showing any of the ugly pex pipe?

Use copper stub outs for pex.  Like this:
https://www.amazon.com/Sharkbite-25094A-Copper-Elbow-Bracket/dp/B016Q4OAKY
It is very difficult to finish pex coming out of a wall nicely.
https://www.youtube.com/watch?v=IVD-ZMC2jA0


Doorbell transformer - Installed in panel -doesn't work when green is connected? Earlier today I replaced my doorbell transformer in preparation to install video doorbells.  The old transformer was connected outside the main panel, and only had 2 wires.  One to hot, and the other to the neutral/ground bus.    Of course, the new transformer has 3 wires (black, white, green).  My first attempt to install, I connected the black wire to hot, and both the green and white to the neutral/ground bus.   Turned on the breaker and nothing - no voltage on the meter.  However, when I removed the green wire from the neutral/ground bus (leaving white and black where they were), all worked fine - so I just capped the ground wire and used electrical tape to stick it to the inside of the panel box.   Any idea why the transformer did not work with the ground wire connected to the bus?  Something special about connecting at the panel? Is the setup unsafe?
Thanks
Happy New Year!

Follow the Instructions
The instructions say:

For metal junction boxes, it is required to connect the green ground wire from the transformer to the metal junction box or clamp it to the metal conduit.

If it doesn't work when connected properly then either you have something very strange going on in your panel or the device is defective.
The fact that the instructions actually say this, rather than "nothing" or "the green wire is only required if you are not installing the transformer on a grounded metal junction box", means that you need to do it for a proper installation. End. Of. Story.

Ground != Neutral
...except when it is :-)
In a perfect world (electrically speaking), ground would only ever be used for two types of current: device/wiring fault and external current (e.g., static discharge or lightning). In order to make everything work properly, ground is bonded to neutral at one place, typically the main panel.
For a bunch of historical reasons (e.g., separate ground wires have not always been a thing), there are a bunch of situations where there used to be, and in some cases still are, ground and neutral together at the device.
However, there is no requirement that ground and neutral be the same and be connected in a device. But there is, generally, a requirement that each device have a ground connection. (There are exceptions - double-insulated tools, simple devices such as wall warts or lights, etc.) With many devices, the case or exposed metal parts of a device will be connected to neutral, whether or not there is a separate ground wire. However, it is quite possible to build a device which has ground to the case (for safety) but which does not connect that ground to neutral because doing so would make the device not work properly. A transformer is a simple example of such a device.
End result: If you have separate ground and neutral connections (screw terminals or wires) on a device then you do not connect them both to neutral unless the directions tell you to do so. Doing so when not appropriate may cause the device to not work (no harm done) but may be deadly.


What is a NON-self-tapping screw? What does self-tapping mean, really? Someone on the site suggested that I use "self-tapping screws", and gave me a link to the Wikipedia page about them.

So, I went there, saw the definition:

  A self-tapping screw is a screw that can tap its own hole as it is driven into the material.

but I know this to be true of a screw in general... and the photos on that page were simply of what I would call "a screw", period:

So what is a NON-self-tapping screw then? How do I tell apart self-tapping from non-self-tapping screws?

Note: I'm not asking about "self-drilling" screws - the ones whose tips look like the end of a metal drill bit. Those are markedly different than what I know as "just" screws.

To "tap" in this context means to cut threads into a hole.  For this topic, we can think of three basic things a screw can do - drill its own hole, tap its own threads, or just force its way into the material tearing out a hole or threads in the process.

Using this image from that wikipedia article:

The top screw is self-drilling.  The sharp, split point acts as a drill bit to create a properly sized hole.  At the top of that drill point, the threads taper up, and this is the self-tapping portion.  All self-drilling screws are also considered to be self-tapping, and the common vernacular is to just call them "self tappers".

The next three screws in the picture have a blunt tip, so they are not capable of drilling.  They require a pre-drilled hole, but they have a notch or flute at the tip, and this is what the screw can use to cut its own threads or "self-tap".  These are pure "self tapping" screws, but you don't see them for sale at the big home stores.  They are used more in industry to assemble goods on a factory level.  You can buy them - they're just not as common.

The Wikipedia entry has it wrong

This picture from the Wiki page is just regular sheet metal screws and shouldn't be on a page describing self tapping screws:

These do not have a drill tip, and they do not have a flute to cut threads.  Sure they are a little sharp, but not sharp enough to make a hole in sheet metal.  They need a properly sized hole.  If driven into a hole that is too small, they will tear the hole wider (if they are stronger than the sheet metal) and create a weaker connection than a self-tapper that properly cuts the right threads.


Rewire outlet without drilling through drywall I have an un-grounded outlet A which is 3 prong (no-no) that is connected with a fairly old (50 years or so) cable to a grounded outlet B. The connecting cable most likely has a flaw (causes breakers to trip) and needs to be replaced.

Is there a way to replace the old cable with a new Romex cable without drilling through drywall? I am thinking that I could (maybe???) fish the new cable using the old cable.

The best way I have found is to break the old box out and remove the staple if possible and possibly use the old wire for a pull but not often will this work. If it won't I  will drill a hole from the attic or crawel space and fish the new romex in. I use an old work box because you can't really secure the box with nails , the old work box hangs onto the sheetrock or plaster. No staples are required behind the finished spaces but they are required in the attic if not run through holes. Have done many old homes this way that were permitted and inspected .
Glow sticks are helpfull (1/8" or larger fiberglass that glows after being in the light) and a coat hanger formed to grab the end of the stick and pull it to the hole and then the wire connected to the end


How do I connect a WiFi thermostat to my furnace's primary control? I would like to install a Honeywell WiFi controlled thermostat to connect to a Honeywell R7184U primary control. My question concerns the "C" wire. The R7184 has the terminals labeled 1, 2, 3 and 4 with the T1 & T2  being terminals 1 and 2. Which terminal do I connect the "C" wire to? It looks like I have 24V coming at terminal #3.

Edit: Sorry, my error the current thermostat wires connect, white wire to terminal 4, and red wire to terminal 3. The new thermostat is a low amp draw which has to be powered all the time, even if the furnace is on or off, so it can communicate with a router.

Judging by the Honeywell R7184A Controller manual, you have one of these:

You described it as terminal 4 but the diagram just shows two terminals labelled "T", but that is fine:

I found a manual for an EnviraCom device which shows terminals 2 and 3 are 24vac power:

This means we have the right connections, and according to the R7184 manual:

EnviraCOM™ Current Available: 150 mA

So the liming factor here is simply the current available. I can't find any specs at all for the thermostat you posted, but so long as it needs 150 mA or less (at 24 Vac) then it should work. You would make the following connections:

Burner             Thermostat     Desc
Terminal 4 T       W              Heating call
Terminal 3 T       R or Rh        24Vac
Terminal 2         C              24Vac "Common"

Note: your current wiring may not have W and R connected correctly, because with the two-wire system it doesn't matter. Now that you need a C wire, it is important to have R connected to constant power. If wrong, your thermostat simply won't get power.

If your thermostat draws more than 150 mA, you're going to run into various strange problems that may range from occasional glitches to your burner not working at all, and I'd highly advise against doing this.

If you do need more than 150mA, normally you could upgrade the transformer -- but in this case, it's all an integrated solid-state unit. I'm actually not sure you could wire this up without damaging the burner controller. The safest thing would be to use a separate circuit with a relay, but that is far beyond the original scope so I won't post how do to that unless necessary.


Rain chains at an angle from the vertical I'd like to hang a rain chain, but not quite vertical straight down -- at a slight angle from vertical.  What angle from vertical can I hang the rain chains, and still have them work?  Are there any guidelines?

It's going to vary with design and rainfall rate. More flow means more likelihood of spillage and drop detachment, so it depends on your personal preference. Add to that the wind around your home and it's hard to say.

Trial and error are the best approach.


Should I have the return line replaced when installing a new heat pump? I have a 2000 sqft. house and need to replace a 4-ton R-22 system that uses a 1-1/8" return and has a short line run with the condenser 8 feet lower than the evaporator.
I have received quotes that recommend replacing with another 4-ton R-410a system, but the quotes differ on whether to reuse the existing 1-1/8" return line or install a new 7/8" line. The manufacturer install guide says that the system is rated for a 7/8" return line and does not mention 1-1/8".
Will a 4-ton unit still be enough with a smaller return line? Will using the existing bigger line cause problems since it's not rated for it?

The size really would not be a problem, the 410 is a higher pressure system and that allows for smaller tubing but will take more refrigerant (not much).
I am not a fan of reusing parts, yes they can be cleaned but I have had friends come to me after a new retrofit failed in less than 2 years.  The cause of the failure new Poe oil mixed with mineral oil that was not cleaned completely. This has happened 2x that I know of , is the evaporator rated for the 410a pressures?
I would make sure they will warranty all work like I said the size won’t be a problem but will they use that to get out of a warranty claim?  Both my friends had systems retrofitted by hvac companies they only knew they cooled the house. Both companies used the existing equipment as the reason for failure , it won’t affect the system but if you re use anything make sure the system is covered by the warranty as installed.
To cover the system they may want to replace the line, don’t let that be a reason for them to deny warranty coverage but it would not be a problem in theory.


How can I combine the two panels in a duplex on one meter? I own both halves of a duplex (200 amps each) which I've converted into one house. I would like to have one energy bill. Is there a simple way I can easily feed service to the second panel from the first panel from one incoming meter/service?

Well, if you have 2x 200A service, feeding that from a single meter would require a "class 320" meter (320A continuous, which is 400A derated 80%, so it matches, even if it does not appear that way at first.)
The odds are (since those are a significant step up in expense for the meter can) that you don't have that for the meters you have now. So you'd be looking at replacing the meter, with any upgrades required for the currently adopted code in your area, which include adding an outside disconnect if it's NEC2020. This could be rather expensive, will require permits and (probably) professionals and the inconvenience of having no power midway through the procedure.
As such, it will probably take a LONG time to pay off if the thing you are trying to get rid of is the monthly service fee on the second meter. Combining the bills should be easy, but may not reduce that any - could not hurt to ask, though.


How much vent fan throughput do I need for my bathroom? What minimum size (CFM) vent fan do I need per cubic foot of bathroom?

Consider a bathroom that is 10ft. X 4ft. X 6ft(height). What is the minimum throughput rating for a vent fan? I want a vent fan that truly performs when it comes to removing moisture, human methane, etc.

Does the height of the duct, from attic to roof, factor in choosing a properly rated vent fan?

Calculating Cubic Feet
The first step in determining what size exhaust fan is needed, is to calculate the volume of the room. To do this, you'll simply multiply the length of the room times the width of the room time the height of the room.

Length = 10 ft.
Width = 8 ft.
Height = 8 ft.

10 ft. * 8 ft. * 8 ft. = 640 ft.3

Calculate Equivalent Duct Length (EDL)
The next step is to measure the length of the duct run, and then apply some additional factors to determine the equivalent duct length of the run. For example, if we had this situation.

Duct type = Insulated Flex.
Duct length = 15'.
Duct diameter = 4".
Number of elbows = 2.
Number of wall caps = 1.

We'll use these numbers, and the chart below to determine the EDL.

So the example above would look like this.

15' of 4" insulated flex duct x 1.5 = 22.5'
4" elbow adds 15' x 2 = 52.5'
1 4" roof cap adds 30' = 82.5'

Which means in our example, the EDL is 82.5'.
Determine Required CFM
Exhaust fans are sized using Cubic Feet Per Minute (CFM), so you'll have to use the two values calculated above to determine the size of the required fan.  To do this, you'll use the chart below (you'll always round up).

Using our example numbers, we'll place our left finger on 640 cu. ft.. Then place our right finger on 90 ft. (because we have to round up).  When we slide our left finger to the right, and our right finger down. we'll see that we need a fan rated for at least 150 cubic feet per minute.
Running The Fan Long Enough
Selecting an appropriately sized fan, is not the only thing to worry about. You also want to make sure that the fan runs for long enough, so that the moisture can be completely exhausted.  It's often recommended to run the fan for between 20 - 30 minutes, after a shower. This is often made easier by installing an in wall timer to control the fan.

When selecting a timer, make sure it's rated for motor (inductive) loads and does not say "Incandescent only".
Everybody Wants It Quiet
In my opinion, getting the hot moist air out of the building is the highest concern.  Though it would seem, some tend to like it quiet while the air is cleared.
You'll find that exhaust fan loudness is measured in Sone, where the lower the value the quieter the fan. If quiet is important to you, you'll want a fan at or below 1-2 sone.  Here is a chart from Panasonic, that might help put sones into perspective.


Can 12 AWG THHN/THWN wire be placed in a buried conduit? My understanding is all buried wire in conduit must be THWN-2.
Per Southwire's spec sheet here the end of the first paragraph reads:

All Sizes Rated Both THHN and either THWN (sizes 14, 12, and 10 AWG)
or THWN-2 (sizes 8 AWG and larger).

It is baffling me that there doesn't seem to be THWN-2 in 12 AWG.
What do folks do for 20A circuits buried in conduit?
Background, I'm doing all this in conjunction with running 4-8's for a separate 35A 240V circuit to a mini-split. And figured I should fix the previous homeowners error of running 12/2 romex in that buried 3/4" PVC conduit.
Upsizing a 20A circuit to 8 THHN just to get a THWN-2 rating doesn't make sense to me, and I'd run into fill issues.  I would then need to upsize the conduit (not out of the question, but seems an extreme path to take).
Running 12 AWG UF-B in the conduit seems to be the other code compliant. While permitted that seems extreme as well and I'm not sure how to calculate fill using 12 UF-B + 4 8 THHN. Again, likely having to upsize the conduit.
I assumed I could just run 2-12 THHN/THWN (20A circuit A) and add the 4-8 THHN/THWN-2 (35A circuit B), and using one of the 8s as a common ground on both circuits. 6 wires total, fill would be 33%.
I'm wondering if there is some footnote in the NEC that says wire under 8 AWG actually only need to be rated THWN in buried conduits. Or if someone actually makes 12 AWG THWN-2, just not SouthWire?

Not sure where you got the idea that you need THWN-2, only.
All you need is the W.
TWN, THWN, RHW, XHW, XHHW, etc. are all perfectly fine, because they have the W that means they are waterproof, that means they can go in outdoor conduit. Most THHN is also THWN and MTW (multiply rated.)
If you are in a situation where the wire temperature may be extreme you might need to get picky for insulation temperature rating; but to be in exterior conduit (buried or not, they are all wet locations), all it needs is the W.


Soot on the fuse when changed A couple days ago, our water pump conked out.  My brother had to change the fuse to get it running again.  He said there was soot (or something like it) around the fuse when he swapped it out.  It was the same as a conking out a couple months ago.

Where is this ash coming from?  Is the fuse box about to catastrophically fail?  It's the same box from when the house was built around 1956.  Just over a decade ago, the power company messed up fixing a line and a quarter of our stuff got burnt out from the surge and they suggested replacing the whole system coming into our house (i.e. the junction box), which we still haven't done.  (Since that equipment is on our property, they weren't going to pay for it, although it's their fault.)

It's probably carbon from burnt plastic (maybe from wire insulation... so charred cloth if the wires are 60 years old). A picture might be helpful.


Strengtheing a weak bed frame I bought a 200x90 cm. bed and assembled it. The bed frame is assembled out of hollow iron rods. After using for a few days I started having back pain. So I checked the bed and found that some of those rods got bent in the middle and that made the whole frame uneven. I want to strengthen it, however I don't have much stuff at hand, and we are in a lockdown due to coronavirus.

I have not thrown out the wooden planks from my older bed. So I thought putting them on the bars will distribute the load and may help it. My question is what is the pattern that will provide maximum strength? I arranged them in a way (see picture) and it already feels quite solid. I will appreciate any feedback. For information, I don't have an electronic drill machine or any such thing; also I don't know how to use them.

Thank you for reading, it is my first post here. :)

That actually looks pretty well supported the way you did it. If you haven't straightened the rods that bent, you should try to do so. Also, if you have any duct tape, put a strip of it on each end and one down the middle to help hold those planks in place. Good luck and stay safe.


Standard height from floor to ceiling? Is there a standard height from floor to ceiling. I want to install some false ceiling (plaster board) ...

I seem to remember there was a standard but i don't remember it

Any help really appreciated

Simple answer,  If your community subscribes to the the national IRC building codes, then the minimum ceiling height is 7 feet for living spaces.  Some towns will allow less in basement rec rooms, but rarely is it more than the 7 foot min.


How do I build a firewall around my furnace/water heater? I'm in the planning stage of finishing my basement.  I'd like to section off the furnace and water heater, and am assuming that I should fireproof that section of the build.

What's the best way to go about it?

My guess would be steel studs and concrete board instead of drywall, and a steel door.

As best I know, a fire rated utility room isn't required by any code for a single family structure. And for multi-family (e.g. condos), this requirement is to isolate each residence from each other and from common/utility areas. So the below advice is completely overkill.

For the room itself, you can use fire rated drywall. This is usually 5/8" thick, and contains fiberglass within the wall to keep its structure during a fire. Use this on all walls and ceiling. Around any protrusions, (HVAC vents, water pipes, etc), you can fill the gaps with fire rated expanding foam (e.g. Great Stuff). This is usually pink/red in color instead of the normal yellow. For HVAC vents, you can get spring loaded dampers that automatically shut in the event of a fire to prevent it from spreading via the ducts. You can get a fire rated solid door, but to do so, you also need to get an outside air source into this room.

All of the fire rated products are to slow the spread of fire, not to stop it completely. The goal is to get you out of the home safely, before it spreads and you're trapped. Therefore, I'd recommend installing a fire alarm that is connected to the other alarms in the house, ensuring that if a fire starts in this room, you'd know about while there's plenty of time to escape. A standard fire alarm in an enclosed room could easily go unnoticed, or allow you to sleep through it.


How can I change a single box in a vaulted ceiling so that it can accommodate a double fixture? Previously, the vaulted ceiling did not have an electrical box.  My contractor made a level box (think letter "A") and it looks great.  It's all dry walled, etc.  The problem is, the light fixture has two rods and the plate is too wide for the surface he built.  Do you have any creative ideas as to how we can accommodate my light fixture without a total re-do??  HELP!
[![enter image description here][1]][1]

I would consider floating the double baseplate down far enough to gain the width you need. I'd add a box extender that's just enough to get it clear of the ceiling.

The baseplate will be floated a bit, but in my experience this doesn't detract from the appearance assuming that you don't have a level vantage point nearby.


Electrical wiring broken I wanted to replace our under cabinet Halogen bulbs with LED. So I got the LED lights from Home Depot and when testing them from an electrical outlet, I accidentally had the two wires coming together and there was a spark.

The circuit breaker did not trip but none of the outlets are working. Here is the picture

That was the wire that I connected to the electrical outlet and the two wires got connected accidentally and got short-circuited.

As a result, the outlet is not working - there is no power coming through the outlet and the other outlets in that circuit are not working as well

Do you think I should replace the outlet?

You probably have a ground fault outlet that has tripped. look around your kitchen for an outlet with a red and a black button on it and reset it. You might have to look in your breaker panel for a breaker with a reset button on it.


What material to tie two cinder block walls together? I am building a 24" high planter made from cinder block walls: Sketch below.
Though it looks like a normal planter, water is pumped in from a pond, and instead of dirt, various layers of increasingly smaller and smaller rocks are filled in. As such, the walls probably need to support a lot more weight than typical of a planter, as there is rocks and water, not just dirt.
For increased strength, I can run something strong from one wall to the other, since I believe pressure will be equal on both walls. The cinder blocks have holes, which could make a convenient attaching point, but their isn't much space between the bricks, insufficient to run chain. Additionally, I need something that won't rust and deteriorate much over time.
Is there some kind of product I can use for tying the walls good so they support the heavy weight of the rocks and water?
      _____________________________
     /                            /|
    /            @  <--flowers   / | <--brick wall
   /            \|/             /  |
  /              |             /   |
 /                            /    /
/___________________________ /    /
|                           |    /
|                           |   /
|                           |  /
|                           | /
|___________________________|/

       ____                            ____
       |  |                            |  |
       |  |oooooooooooooooooooooooooooo|  |   (slide view)
       |  |                            |  |
       |  |     (rocks + water)        |  | <-- three 8"x8"x16" cinder blocks tall
       |  |                            |  |
       |  |                            |  |
_______|  |____________________________|  |_______<-- ground level

The normal way would be reinforcing bar around insides of the blocks, then add concrete. This is called a "bond beam". Blocks with open ends are used.  If you use enough reinforcing it can be very strong.
For your way stainless threaded rod, you probably need to go to a fastener specialist for that. (or stainless rod and you thread the ends, but threading stainless is hard)
or stainless, or aluminium flat bar and you drill the ends and put bolts through crosswise. aluminium will probably last 5-10 years, stainless much longer.


Water leaking inside outdoor electrical box. What should I do? I have some very old outdoor path lights in my front yard (see pic). Recently I found that they trip my upstream GFCI outlet when they were turned on by the timer at night. After some investigation, I found one of them is the root cause of the trip, and I realized the electric box is filled with water once opened... I closely inspected and think there are three possible places where the water could come in:

upper hole that connects to the light cover, which admittedly already has some crack on it and it is not very tight and water sealed.
the front plate itself, which has some soft cushion around the plate that I think is for sealing
the two pipes under the box, for whatever reason the water might come from the ground?

The things is, I tried to use teflon tape around 1 and clean, retighten 2, there is still water inside after some rain last night. I am wondering what I can do to fix this. Since these lights are buried in the ground, I am hoping I can fix this particular one instead of ripping them all out.
More info about the light: they are so old that I couldn't find much info. It seems all the replacement pathlights that I can find in home centers are low voltage ones (12v). However, these lights connect straight into a mechanical timer in my garage, which is using regular 110v voltage.

That’s a standard weatherproof (Bell) box, and yes, sometimes they do accumulate and hold water as you have found.
Code not only allows boxes to be drained.
Code requires boxes to be arranged to drain; according to 314.15, a 1/8” hole is allowed.
I have found conduit bodies and boxes at a low point (at the bottom of a hill or conveyor) to fill from the bottom, and others to fill from the top. It’s not important, just drill a hole in the bottom and you won’t have any more problems.
So turn off the power and drill a hole and forget about it.


Actual efficiency of an old oil furnace? We purchased a house with what appeared to be a relatively well-maintained oil furnace, about 30 years old (installed in 1984). We don't have any records of annual oil usage, or any way to find that out. From what I can tell, it was originally 80% AFUE.

Energy.gov says old heating systems may be operating at 56%-70% AFUE.

Is there any way to guess what the actual AFUE for this furnace may have been? It's been removed, so there's no way to test anything at this point. The furnace appeared to be well-maintained, and was fully functional. Is it really conceivable that the AFUE could have been as low as 56%? That's a waste of nearly half of the energy! Could it have even been lower? Is there any place where I can find an average AFUE for furnaces of a certain age?

There is no way to determine with any certainty what the AFUE was for the boiler in the past. A service technician can check the flue gasses with a flue gas analyzer and determine what the AFUE currently is.

A boiler can keep operating near its original efficiency as long as it is properly maintained. On an annual basis, at minimum the following things should be done: replace the oil filter, clean out the boiler and chimney, and replace the nozzle.

Basically everything on a boiler is replaceable. If you have the knowledge, you could theoretically keep a boiler going indefinitely. You can even replace the lining on the firebox if it wears out. The kits to do this are relatively inexpensive and can increase the life of the burner for many years.

If the boiler is still running well, there most likely is not a need to go out and replace it right away. Even the new high efficiency oil burners are only rated between 86 and 87 AFUE. It would take many years to make up the cost difference.


Why won't this bed's feet touch the floor? My wife and I just got a hand-me-down Queen-size bed after our old one broke. It was disassembled and brought to us by people unfamiliar with its previous assembled state.

You might be able to tell that neither the two wheels on the feet nearest the headboard nor the two feet in the middle are actually touching the ground. That's my problem.

Here's a close-up of the feet at the head and the connection between the frame and the headboard.

The metal plates on the headboard looks like they were made to accept several different kinds of frames — the ones with hooks, for example. But of all the holes in the metal plate, the only ones drilled through the headboard are the ones these bolts go through.

The three pieces of wood also came with the bed. None of them is thick enough for the currently-hovering feet to rest on. You can slide them under the hovering feet easily without lifting the frame. One of them has a screw sticking out of the end, so it doesn't seem like they were supporting the box springs.

Is there any chance that this bed was assembled properly at its original location? Did we do something wrong? Is it safe (for the bed) for us to sleep in it with only the headboard and the wheels at the foot of the bed holding up the frame? That doesn't seem like it's going to be enough support, and a similar problem caused the demise of our previous bed.

It is a possibility that when the previous owner set it up originally they set it up that way for medical problems, like excess stomach acid.  I've been told by doctors to raise the head of my bed before, but I never did.  He just told me to put wood underneath the feet or wheels at the head of the bed.

If any of the screw holes match up where all the feet rest then try that.  If the wood is not drilled out behind the holes you choose then pre-drill them.


Electrical main panel flush mounted in concrete wall It is possible to install an electrical load center flush mounted (recessed) into a concrete wall? I've seen plenty of junction boxes (outlets) embedded into concrete or masonry but can't find any examples of load centers installed this way, only flush mount installations being between studs. I couldn't find anything regarding concrete or masonry installation in installation instructions or specs. Considering its larger volume I can see how it might cave in or deform in while concrete is poured.

I'd like to do this in a garage where the walls will be concrete but can't think of a reasonable way to connect conduit if the load center is surface mounted.

Edit: Located in WA state so currently NEC 2017 is in force, later this year going to be NEC 2020.

Oh heck no, don't do that.

Imagine you found the perfect house.  You love it too, but your partner also made clear that you that you weren't "getting any" except in that house's bedroom.  Except, somebody concreted a 12-space FPE Stablok into reinforced concrete, conduits going through it and all.  Your insurance company is saying, "If you want insurance, that HAS to go".    What sort of choice four-letter words would you have for whoever who  thought it was bright idea to concrete that in there in 1983?

Of course there will be no choice.  You'll have to stick a new service and panel in an awkward and unsightly place, bypass that panel altogether, and rewire the entire house.  And it's made of concrete, so the only way that won't bust the budget is conspicuous Legrand Wiremold all over the walls and ceilings.  Thanks loads there, Humphrey!

If there's anything experience teaches us here, it's that changes to service panels are often necessary.  Far beyond ordinarily "adding circuits", people have serious problems that require panel replacement.

They find out they are dangerous Zinsco or FPE StabLok firestarters, that have to go.
They find themselves with a Crouse-Hinds or Pushmatic that is inherently obsolete and simply cannot meet today's standards.
It doesn't have those problems, but it's a dangerous "Split Bus/Rule of Six" panel (which, granted, can be solved by subpaneling if the service wires are in conduit).
They don't have enough spaces, because the same genius who set it in concrete also picked a 16-space panel. "But it's 32 circuits!" which buys you nothing in NEC 2020.

Of course, that's what we know today about 1980's panels.  What will we know tomorrow about today's panels?  Will we find out that Square D HOM's relatively young plug-on neutral scheme is as dangerous as FPE/Zinsco?  Will GE drop all support for older panels (again) just as JFCI breakers become mandatory?  We don't know. That's the point.


What is the easiest way to install 4" recessed lights in 6" holes? I purchased some nice-looking 4" recessed LED fixtures to replace my existing fixtures that use incandescent bulbs.  I've now discovered that my current recessed lights are of the 6" variety.  I like the size and appearance of the 4" lights better than any 6" fixtures that I've seen.  How hard it is to "shrink" the holes in the ceiling so that 4" recessed lights will work.  What's the best way to achieve this?

Four inch and six inch recessed fixtures consist of two main parts - the can and the trim. They need to match.

The first issue will be getting the old can out. If it is old-work style, it may be held in just by pressure clips on the sides, fairly easy to remove. If it is new-work style, it will be attached to framing members, either directly or with a brace system. More complicated to remove and usually requiring cutting a bigger hole to get to it.

Even if it is old-work, a 6" hole differs from a 4" hole by 1" on each side. Cutting a 1" ring from drywall is hard, leaves you with a fragile piece, and will be difficult to tape and mud smoothly, and hard to brace properly.

I would suggest cutting a somewhat larger square out of the existing ceiling area. This will allow you to remove a new work can, if that is what you have. Leave at least 2" on each side of the hole. I would cut the new 4" hole (check the fixture for exact hole size) before mounting the patch to the ceiling.

Once you have a section out of the ceiling, you may be able to reach the framing to attach a new-work type unit. More likely, you will use an old-work style.

In either case, you will need to brace the new patch to provide strength to hold up the patch and possibly the new fixture. You can do this by using furring strips that are at least 6" longer than the size of your patch. The furring strips will extend on either side of the patch.

The strips should be screwed to the ceiling beyond the patch and the patch should then be screwed to the strips. I would use 4 strips, all parallel, two on the outside edge of the patch and two just a bit wider than the location of the new 4" hole.

Once the patch is up, tape and mud (spackle) the edges.

Finally, you might want to think about moving the new fixtures to a slightly different spot to get a solid surface to attach to. This may require some adjustment in wiring.


Forgot washer when after building a desk I just finish building a desk. I already drilled holes prematurely (not deep, the table top isnt pre-drilled) and force my screw to fully go in.
It includes washers that is meant to be between the table top and legs but I totally forgot about it!
Should I take it apart to put in the washers? If so, would I run the risk of having the screw not being able to screw tightly (with/without the washer)
The washer is about the 50% of the hole depth.

Take out the screws, put the spacers in, replace the screws and tighten snug to firm, but not hard. See how it performs.


Should I make space for a new 50A breaker in a full panel or install a sub-panel? I'll start by saying we just bought a fixer-upper house.

I searched the topic of adding sub panels and a lot of the answers are a bit over my head so I need some advice.

My house was built in the 20's.  At some point in the last several years, someone updated the electrical stuff to a familiar breaker system.  The wiring looks modern and insulated and it also looks like things are grounded as far as I can tell.

What I want to do is install an electric stove which requires a 50 amp circuit in place of the deathtrap gas oven (it was old, the line to it had leaks, and I like cooking on induction.)

What I have, I think, is 100 amp service in the breaker box.  The breaker box is full, no slots to add a 50 amp breaker.

So what do I do?  Should I add a sub-panel?  Should I yank the existing panel and put in one with more slots?

In my mind I would think I would put the heavy current circuits like A/C, Oven, and clothes dryer on the sub-panel.  That's how it was in my last house.

Anything I do, I'll spend the money to have a licensed electrician to make sure it's up to code, but I want to do the actual work myself.

The house is a single family.  Two stories for about 1200 sq ft and an unfinished basement.  No outbuildings, garages, wells, etc. Gas Heat, Gas Water Heater.  Central A/C.  electric clothes washer and electric dryer.  I want to install a 50 amp electric range as cheaply and safely as possible, but I want to do it right, and of course the wife wants it done right now :)  I'll add pictures tomorrow, probably.  Current idea is to double check the gauge of the wire that runs to the clothes dryer to make sure it's heavy enough to handle the stove and then beef up the breaker and receptacle, just to get it done fast.  If we do that, we will be able to cook, but not dry clothes, so I'll be in the same place in a month or two.

Some additional information.  The breaker box is a Challenger brand SLB12 (12-24)CT.  125 amp max.  The Main breaker in there is 100 amps.  There is already one doubled up breaker in there.  I was incorrect, there is one available slot in it.  Will add pics soon (they are too big for SE and I need to edit them).

I would start by putting a rather large subpanel as close as possible to it, probably whichever Siemens panel ThreePhaseEel recommends, or a CH or QO if space is an issue. 42+ space.   Position it with an eye toward rerouting the service wiring there.

Even before that, talk to the power company about upgrade options.  If a particular size is possible, get the subpanel with that main breaker, but don't sacrifice spaces to do it.

Short term, if the new subpanel is >=100A it doesn't need any main breaker at all, or even a main-panel breaker.  The main breaker in the main panel will protect it.  Use at least 100A wire to connect the panels, i.e. At least #3Cu or #1Al.  A reason to use cheaper Al on such a short run is the lugs will be aluminum.

Having a breaker in the main panel can be avoided with a lug-breaker, which snaps in like a breaker but has only lugs.

Now, at leisure, move one circuit at a time from the old panel to the new.  That's just to get away from those somewhat dodgy Challenger breakers. If wires don't reach, I typically put 4-11/16" square boxes at opportune locations to splice. Ideally metal conduit the rest of the way to the new panel, and THHN wire inside the conduit.  Ideally.

With all the circuits moved over, try to straightline the subpanel straight off the bottom (switched side) of the main breaker.

Alternately, if the power company's upgrade path calls for a new meter pan, get one with a main breaker.  Gut the old panel, using it only as a gutter, to the new subpanel, using wires rated for main breaker current.  If that's the plan, you can use a main lug subpanel instead of a main breaker one, saving some space.  42-space main lug CHs are not that big.


How do I source, remove, and prevent green mold on my aluminum windows? I live north of the equator in a humid climate.  The 2 north-facing windows pictured below only get direct light (lots of it) in the evening.  We get a lot of rain.  There is green mold growing from the windows for some reason.

I want to

determine why I'm getting this mold
clean off / get rid of the mold
prevent it from coming back without having to replace the windows.

The white on the stucco between the lip of the window and the stucco is unpainted white caulk that has been there for 2 years, and that I should have painted, and will once I clean off the mold.

Click for full size image

Mold and/or mildew (yours looks like mildew, but no big difference in regards to abatement) are both fungi and will grow where dark and damp conditions exist.

1) The cause is moisture.

2) You can clean if off easily with a scrub brush and soap, but to help prevent regrowth you should chemically kill it. A 1/4 cup bleach/1 gal. water solution will work or there are numerous consumer cleaners with bleach that will do it.

3) Take steps to keep the area dry, like rain gutters, an awning over the window, etc. Thoroughly clean, caulk and paint the stucco with a good quality exterior paint (most have mildew growth inhibitors). Chemically killing it will help prevent regrowth but be prepared to repeat if moisture cannot be controlled.


What is the proper waterproof bathroom underlayment for vinyl tile flooring? This question discusses vinyl tile flooring underlayment in a bathroom, but fails to address how waterproof the answer can be.

In my project, we have water-damaged bathroom subfloor and have pulled out vinyl flooring that was on top of it and then cut out the subfloor in order to replace it. In our replacement, we're going to use thin vinyl tiles instead of rolled out vinyl flooring. We plan to put down 1/4 inch birch sheets (someone told me it was called "luon") on top the replaced plywood subflooring. Between the luon and the plywood subflooring, I was told to use self-leveling compound. But then we planned to put the vinyl tile squares right on top the luon. My worry there, however, is that even if we place the tiles very close together, water will seep through, hit the luon, and bubble it. So, my question is -- are we supposed to put a material or flooring on top of the luon before we put the thin vinyl tile squares?

I'm wondering if we should be using concrete board instead of luon, and then put the vinyl tile on that, or if we're supposed to smear some compound on the luon to waterproof it, or some other thing we're supposed to do so that water that leaks to the luon won't cause it to bubble.

Concrete board would be your best bet as long as it is smooth if not you will have to use floor leveler and I would suggest using a mesh tape on the seams with floor leveler or other type of compound so the tile does not crack. There is many types of waterproofing you can just roll on with a paint roller and paint brush. One other thing to consider is using a glue both waterproof and keep the tile in place.


Is installing a gable fan worth the investment? We have 2 gable vents in our roof (approx 2' high or so), one at either end, and upon inspection it does not appear that there is really enough overhang in the roof for soffits.  I still have to inspect it closer from the outside, but they are for sure not installed at this time.  The roof is also slate, so going in through that is not really an option we'd like to pursue.  If we install a attic gable fan on one end, will there be enough air flow through the attic to make this project worth our while in terms of heating/cooling costs, or should we go another route?

I can tell you from experience in my house  a slate roofed colonial, it will make a difference. Even with the fan mounted in an attic window that is that is 3 inches off the floor of my walk-up attic the temperature drop in the attic was 30 degrees.Most fans will have a spec sheet telling how many square inches of ventilation opening they require. It is important to remember that you are calculating square inches of unimpeded opening so subtract for louvers and other obstructions. In my case I have a large peak where hot air tends to get trapped. If we have several days of very sunny and hot weather I place a small table fan on the attic floor. With the small fan pointing up it circulates the air to remove the hottest air trapped at the ridge.


Can I put a shower pan where tile USED to be? I pulled up the tile in my bathroom. Water was underneath and had rotted the wood nearby. Now I have a concrete pan underneath where the tile used to be that slopes toward the drain. Can I put a shower pan over this concrete pan? If so, do I need to extend the shower drain?

At this point you really should do it right.  Since this is the basement floor, you will be placing the shower pan on the concrete.  You'll want to adjust the drain so that it can connect correctly to the shower drain.  If this concrete is already sloped (and it sounds as though it may be) you may be able to remove the sloped part if it was poured on top of the slab. Otherwise you could use some leveling compound to create a flat surface for the shower pan.

I'm assuming now that the rotted wood was in the walls.  You should use a product designed to back shower tile such as a cement backer-board rated for this use.  Your building materials supplier should be able to get you the right product.  Follow the manufacturer's recommendation for proper installation and surface preparation needed before applying the tile.

Be sure to remove and replace all the rotted wood while you have this all exposed.  It won't get better on its own.


Replace switch with dimmer for lights on two fans The two lights are wired to one switch. The fans are wired to the other switch.  Can I install a dimmer just to control the lights and use a one pole since there is only one switch?

Yes you can do that. Turn off the power and remove the two wires from the old switch and hook them up to the two terminals of the dimmer.


Ceiling light fixture wires - entirely in box? For new overhead light fixtures like this that normally come with long-ish wires, is the entire length of the wire supposed to be in the electrical box?  I assume that the part with the wire nuts must be, but does code allow for the rest of it to sit on top of the fixture's insulation but outside of the recessed box?

There is going to be some of the wire loose above the cover to allow the fixture to be wired 410.20. I don't see a specific length listed in section 410 (luminaries, lamp holders & lamps). Installing the fixture per the manufacturers instructions is the key because there are so many diferent types code doesn't always give specific requirements. An example of this would be a 4" canopie or shell may only need 6" of free wire to be able to make the connections but a 12" canopie or shell may require 8-10" to make the connections. Hope this helps.


Adding old-work box without making a large hole? I am changing out the vanity light, above a sink and mirror, in a bathroom.

The old light fixture had it's own wall plate screwed to the wall that the wires ran into from a hole in the drywall behind.

The new light fixture (just under 10lb in weight) requires an electrical box (as well as being a code requirement.) This house was built in 1980 and does not have an electrical box in the wall so I need to add one.

There are no studs within a few inches (the light needs to be directly above the sink) so I could use a braced box like this:

But I'd like to avoid tearing a large hole in the drywall if I can safely avoid it.

So, I'm thinking I could attach strips of plywood behind the hole to spread the weight out over a larger area and add one of these:

The ears of this would rest on the plywood. This way I don't need to make a hole larger than the box.

Do you think this setup will hold a 10lb fixture (assuming the drywall is OK) or should I just rip the hole and add the braced version?

The braced versions are designed to be installed through the same 4" hole that you'd use for the blue 'old-work' box. I wouldn't trust a 10lb light fitting to be kept up only by the strength of drywall - especially in a damp environment like a bathroom.


Just installed a new sconce. When I turn it on, I blow a fuse!!! Help? I moved to this house a year and a half ago and have replaced about 9  sconces so far with no problems. I replaced one tonight, and when I went to turn it on, I blew a fuse! Never happened before. I had to wait a whole hour to be able to reset it and the second I tried it again the lights went out again :( I think this might be the only sconce that has 2 switches to turn it on. I didn't change the switches though, only the light.  Help! I don't want to call an electrician like google suggests. They are extremely expensive and scarce around these parts!

If all you changed was the light fixture the Hot and neutral may be reversed with a grounded fixture when you turn the power on it goes to ground tripping the breaker try reversing the fixture connections as that should fix the problem if this was the only change. Many times wiring in switch loops are not properly marked and are easy to get reversed.


Reading the measurement of the slope of a floor I have been told the slope of a floor is 2.5 degrees. How does that translate to the dropping of the floor so many inches in four feet?

48 inches Tan(2.5 degrees) = 2.10 inches.

or a 4% slope.


Do shower doors for tiled openings have to fit the width exactly? So I just measured my cement board to cement board width and before tiling it is 4'11".  This is due to the pan instructions of putting the pan 'against' the frame.  The pan is cast iron covered in porcelain so I would not have to tile that.

I was thinking I could buy a standard shower door of 5" but the pan instructions screw that up.  Once tile is in, I am guessing 4 foot 10.5 inches is left.

Are there 5' shower doors you just cut down and the glass overlaps more?  What are some suggestions here? Last time I was at home depot, all the doors were of a fixed size.

Thanks.

Almost any such door has a range of adjustment or applicability, often in the form of panel lap. Tiled openings just aren't that precise. Look at the installation manuals for any models you like. They'll tell you what the range is.

For example, this one specifically lists 56-60".

  Up to 4 in. of adjustment for width, if needed


Installing a 240V 30 A outlet for EV charging I would like to install a 240V 30A outlet for EV charging in my deeded parking space in the common basement garage in my condominium building.  The electrical closet with all individual unit electric meters is conveniently adjacent to my deeded parking space.  Rather than drill a hole through a steel reinforced concrete floor from my unit into the garage to run a wire from my in-unit main breaker panel to the EV charging station, can I do the following:  1.  install a new main breaker panel between the unit electric meter (in the electrical closet) and the in-unit breaker panel (thus making the in-unit breaker panel a subpanel); and 2. run a wire from the new main breaker panel (which would be physically located in the electrical closet in which the unit electric meter is located) to supply my 240V 30A EV charging station?  The condominium is located in Cambridge, MA.

First you have to consult with your Condo HOA to see what their restrictions are and then proceed per their instructions. Otherwise your thinking about putting the mains by the meter and sub feeding your home panel and new charger is the least expensive and least intrusive of your options.


Can 2 wires of a higher gauge be used in place of 1 wire with a lower gauge? I need to wire a 220v 55 amp circuit in the attic for a new HVAC system.  I would normally run a single 6 gauge wire to handle the 55 amps.  However, I already have 2 10 gauge wires run to the attic.  Can I connect the 2 10 gauge wires together at both the MSP and the box in the attic and protect it with a 55 amp breaker and have it function the same way as a single 6 gauge wire?

No, you cannot parallel that size conductor. Rule 12-108 states that conductors smaller than 1/0 AWG cu or al cannot be paralleled. You will need to run the larger wire.


Why would lights plugged in to lamp holder outlet adapter be testing as live? We bought an old pendant light for our flat, with a two prong plug.  Rather than rewiring it in to the existing outlet, I just bought one of those $2 lamp holder outlet adapter.  To be on the safe side, I checked it with my contact volt tester, which lit up when it came within a few inches of the unit (not even in contact).

I plugged the pendant in to a standard wall fixture and all was fine (no charge on the casing, the tester only lights up with contact on the cable).  What's more, when I plugged our bedside lamp in to the ceiling adaptor the same thing happened - a good 2-3 inches out the fluke lit up.

Is there something about those outlet adapters which may be causing the pendant and lamp to be live?  Or perhaps the ceiling fixture is rated too high for the pendant and lamp?

I would advise checking the wiring of the switch.  It sounds like it might be a case of the switch for the lamp is switching the neutral instead of hot. The result of this is that when the switch is off, there is no visible light because there is no return path for the electricity (broken by the switch), but there is still eletricity making it up to the fixture.


What type of rheostat can I use to control an LED bulb? I am making an Edison wooden lamp and instead of a toggle on/off switch, I want to be able to dim the lamp.  The bulb I am using is rated at 6 Watts.  What type of rotary rheostat should I use for the dimming function?  It needs to work at 120V.
Many rheostats I am seeing are rated for 100W which may not properly dim an LED given their low wattage.

I don't think you can.   Get a dimmable LED and use a standard inline light dimmer.


How can I drill through a Linoleum floor? I would like a drill a hole through my dining room floor to run a wire. The floor is carpeted, so I pulled back the carpet in the corner to find an old linoleum floor.  I attempted to drill a hole through it, but the linoleum seemed to melt and then form an impenetrable barrier. What type of drill bit could I use to get through the linoleum and the wood below?


Heat causing concrete to heave I mostly hear about this happening for roads on very hot days, but I'm wondering what about the heat causes the concrete to heave? Is there any concerns for foundations/garage floors/drive way heaving for the same reason? If so, what can I do to protect them?

heat causes it to expand. If there's no room to expand, it buckles. It's usually a bigger issue for blacktop, as it's darker and absorbs more heat. I doubt your house foundation or driveway has enough exposed mass for this to be of any concern, though...you typically need highway amounts of surface to cause the buckling


How to test if both Hot wires are disabled without Neutral? Supposed the breaker is off but the left side is still hot (let's say breaker defective). Won't it work if you measure the terminal in the hot right and load left like in the following picture?

Why won't it work (if it won't work)?

Original message:

I'll connect two chair lugs to the screws in the above 125A main breaker feeder cooper. If I shut down the main breaker, how do I check both hot wires are gone without any neutral (we don't use neutral since all our equipments are 240v)? A defective breaker may only disable one of the hots. If I use a multimeter, where will I put the other lead on for each?

That's what a non-contact tester is for. You test with it before and make sure it is showing voltage and then flip the breaker and make sure it is clear. It should not be the only thing you do before working on potentially live wires/equipment, but it provides a very useful double-check.


Which side of a sink should I install a garbage disposal in? I am about to purchase a garbage disposal to install myself. Our kitchen sink has a large, deep side, and a small, shallower side. Which side is more appropriate to install the disposal in?

The small bowl is typically called a veggie bowl. The idea is that you use the large sink for cleaning dishes or soaking and then the other sink is available for prep usage, peeling etc.  So, the disposal would go on the small bowl.


Warped siding letting mice in Some of my 40yo T1-11 siding has warped leaving gaps at the bottom between it and the house. I think mice may be entering through these. I was told not to caulk because moisture might build up. Other than replacement are there options?

Re-nail the bottom of the T1-11 to the sill plate every 6 inches. I use Simpson StrongTie ring shank stainless steel siding nails. Be sure you know where any water pipes and drain lines are in the exterior wall, and use the length of nail that would not go much more than 1 inch into the sill plate. You could go 1.5 inches into studs low on the walls where there would be no pipes or wires.

Simpson StrongTie stainless steel siding nails


What size feeder do I need for an RV shore power panel? I'm looking to install a shore power panel for an RV, which will have a 50-ampere, 30-ampere, and 20-ampere receptacle in it. Each receptacle is protected by an appropriately sized circuit breaker, that is built right into the panel. The panel will be similar to this one.

I have a 50 ampere GFCI breaker in my main service panel, as well as a length of 6/3 with ground cable (decommissioned Hot Tub circuit). Can I re-purpose this circuit to feed the RV panel, or do I need a larger feeder?
Reading through the National Electrical Code section 551, it seems to me that I should be fine.

National Electrical Code 2017
Chapter 5 Special Occupancies
Article 551 Recreational Vehicles and Recreational Vehicle Parks
551.73 Calculated Load.
(A) Basis of Calculations. Electrical services and feeders shall be calculated on the basis of not less than 12,000 volt-amperes per site equipped with 50-ampere, 208Y/120 or 120/240-volt supply facilities; 3600 volt-amperes per site equipped with both 20-ampere and 30-ampere supply facilities; 2400 volt-amperes per site equipped with 20-ampere supply facilities; and 600 volt-amperes per site equipped with 20-ampere supply facilities dedicated to tent sites. The demand factors set forth in Table 551.73(A) shall be the minimum allowable demand factors that shall be permitted in calculating load for service and feeders. Where the electrical supply for a recreational vehicle site has more than one receptacle, the calculated load shall be calculated only for the highest rated receptacle.

According to this, it seems as though the calculated load for the panel would be 50 amperes (based on the highest rated receptacle), and the feeder should be based on 12,000 VA (12,000VA / 240V = 50A). So I should be fine with a 50-ampere breaker and 6 AWG conductors, right?

Where the electrical supply for a recreational vehicle site has more than one receptacle, the calculated load shall be calculated only for the highest rated receptacle.

clinches it.   However, this presumes this is one site.  If it is reasonably plausible that this is 2 sites, and Junior could roll up and park his TT30 right next door -- then yeah, you'll have a problem.

And I would address that problem by fitting a generator interlock so both the 50 and 30 can't be on at once. I wouldn't worry about the 20.

Also, build a birdhouse with a door over that thing.   You'll thank me later (actually you won't though).


Different Pressure in Parts of the House We are in the middle of remodeling our house. The water pressure in the bathroom is low but at the outside back faucet it is very high. The shower head doesn't have enough pressure to run it correctly. And the pop-off valve on the brand new water heater is leaking every time we run hot water. Any suggestions what may be going wrong and how to fix it?

You possibly have galvanized steel pipes which when replaced with PEX or copper would fix your low water pressure. I'm not sure why galvanized steel was ever used for water pipes, but you can use a magnet to tell if they're steel or not. Other than being a different color than steel, copper isn't magnetic and steel is magnetic.

Your T&P valve on your water heater will leak for 3 reasons. 1 if the pressure is too high, 2 if the temperature is too high, or 3 the valve is failing.

Reason 1, your pressure too high, can be corrected by adding an expansion tank to your hot water line. Water expands when heated, and it needs somewhere to go or it'll build up a pressure much higher than your normal water pressure.

Reason 2, your temperature is too high, can be corrected by turning down your water heater temperature. The US Department of Energy recommends as low as 120F, 140F is the most common, and it really shouldn't ever be set higher than 160F because the scalding/burn risk is extremely high at that temperature.

Reason 3, your T&P valve failed, is unlikely since it is new. Typically they fail where they never seal or never open. So it leaking only when the heater turns on makes it more likely to be reasons 1 and/or 2.


Is a dryer vent tube being compressed like this up to code? There's a 4" dryer pipe in my wall that is smashed slightly in order to get it to fit into the wall made with 2v4s. Is this OK?

I can't answer whether it complies with code or not since that depends on where you are, but I doubt it would matter.

It's compressed some, but the volume is the same; it's just a different shape, and only slightly at that. Codes regarding airflow (and water flow) issues are mostly concerned with turns. A 90 degree angle will limit airflow whereas a larger radius bend would not, but the straight runs are rarely if ever a problem.


Do air compressor quick disconnects seal on both sides? I realize the air pressure quick disconnects are self-sealing, but do they seal on both the male and female end ? or is it only one way?

No.  Only the female end self seals.  The male stays open, at least on my cheapo version.


What causes a HVAC control transformer to overheat? I recently replaced my 24 volt HVAC control transformer. The outside unit started up including the air handler and ran for maybe 10 minutes. After the units shut down I noticed that the transformer was hot to the touch and no longer is working.

What causes this and how can I fix it?

Underpowered transformer
Sounds like you may not have gotten an equivalent replacement.  When looking for a replacement transformer, you should be concerned with

Input, or primary voltage
Output, or secondary voltage
Volt-amperes (VA) rating.

If the transformer is not designed to supply the amount of current needed by the components on the circuit, it will overheat and likely die. Current generates heat. The more current that flows through the transformers coil, the hotter those tiny wires get. Get the wires too hot, and they will break. Heating and cooling cycles of the transformer can cause the wires to become brittle, which can also lead to failure over time.
If you've recently added components to the system that draw power from the transformer (WiFi thermostat, electronic dampers, etc.), you may have to upgrade to a transformer with a higher VA rating. If you replaced an old transformer with a new one that had a lower VA rating, that could explain the overheating.
Short on transformer secondary
A short somewhere in the circuit on the secondary side of the transformer, could also lead to overheating.  Often times the secondary circuit has no overcurrent protection (fuse), so it can be easy to overload the circuit and not know until it's too late.


Wiring 4-wire Electric Range - Can I use these connectors? Our electric range is hardwired to a 40 Amp circuit with 4 copper wires (ground, black, red, and white neutral). I don't think it was ever installed correctly since each of the bare wires was just screwed into the terminal block without any terminals.

I want to do this right for our new range, so I bought some terminal lugs but I'm not sure if they are safe to use because of the current requirements.

Oven Terminal Block:

Terminal Lugs:

Some lugs had a max temperature warning of 90 degrees Celsius but these had no warning. Am I safe to use these?  Will they be able to handle the load?  Will there be any copper vs. aluminum mismatch between this and the terminal block?

I believe the main 3 wires coming out of the wall are all 8 AWG 7 strand.

Here is a link to the terminal lugs for reference:
https://www.alliedelec.com/thomas-betts-btc0208/70092679/

If you have 3 wires coming from the wall (hot hot neutral, no ground), then you hook the wires to the 3 terminals that you see.  Note the odd little strap linking the neutral stud to the chassis of the range.  It is "grounded" to neutral.  Any fault with the neutral wire will energize the chassis at one of the hot voltages.  Yikes.

If you have 4 wires coming from the wall (with ground), a little work is required, but this increases safety. First you remove that odd little strap, as you will be connecting neutral and ground separately.  Then you attach the ground wire to that green terminal you just removed the strap from.  That lug in your photo is a fine method to do that!  Then you connect hot-neutral-hot to the 3 studs, much like the above.

The T&B lug connectors in your question are certainly good for 40A.  UL would not let them label for #8 wire if they were not good for 40A.  They are undoubtedly a good choice for ground wire. For "hot" wires, after torquing their screw to spec, I would wrap them with shrink tubing or electrical tape.

I agree with 'Bat that the T&B connectors are a little concerning as far as hitting the chassis or something else.  That compartment doesn't apear to have a cover, and they seem awfully exposed.  See how they fit (you are sure to be able to use one) and make a judgment call.  As far as the ring terminals he is recommending, you will need larger ones that fit on #8 wire.  They do make those, but not necessarily insulated.  Then you can shrinkwrap them with shrink tubing.  Just use black.

Uninsulated is good, though, as you can solder them with a nice large soldering iron, not the electronics pencil types but either the inductive gun type or the really big 16" long types.  For the solder, go out of your way to find old fashioned lead solder (non-RoHS; RoHS compliant unleaded solder will crystallize over 10-20 years, it is a death sentence for any eelctronics built that way). Do not use plumbing solder, it's acid core and not lead.

On a 3-wire connection, the neutral is so important that I would not trust a ring crimp terminal alone.  I would use one of the T&B lug connectors, it doesn't matter if that makes contact with chassis.


Can a 220V AC to 12V DC adapter be plugged into 120V mains? I ordered a piece of equipment with a small low-RPM electric motor that came with DC adapter. It's marked

ANGEL
MODEL SG-4805
DC 12V
AC ADAPTOR
HA 10025-2003A
AC 220V 16VA
50/60Hz
DC 12V 850mA

Can it be plugged into 120V mains (safely, and without loss of performance)?

When I look around on the internet, I see some adapters that state the input like INPUT: 100-240V but this one does not give a range.

It would not be a good idea to try to plug it into 120V.

Internally, that adapter is likely to have one of 2 options.

Option 1: A simple transformer/rectifier/capaitor arrangement.
In this case, since the transformer windings ratio is fixed, you should expect to get about 6.5V out (12/220*120).
Although supplying a low voltage to your motor isn't likely to do much (if any) damage, it certainly won't perform as you'd like it to.
It will probably also be much easier to stall - which could lead to some damage to the motor and/or adapter.

Option 2: A switch-mode power supply.
In this case, the incoming mains AC is rectified & smoothed to high(ish)-voltage DC and this DC is then 'switched' through a much smaller transformer at a much higher frequency than the 50/60Hz mains (typically many 10s of kHz).
These circuits can be designed to operate from a very wide range of input voltages, but this is not always the case as it would likely increase the cost & complexity of the circuit.
If your adapter was designed for a wide input range if would probably be marked as such.

The fact that your adapter's specs include a 'VA' rating lead me to strongly suspect that its an 'Option 1', since transformers are rated in VA.

You should be able to source a suitable replacement locally. The specs you should be most concerned with are the output voltage (12V) and current (no less than 850mA - more is ok).


How close to plumb to deck posts need to be? I'm building a deck as the floor of a 30' yurt. Construction is 4" x 6" joists on 4" x 4" posts, on pre-cast concrete pier blocks, on tamped gravel footings. Posts are 20" - 30" long. Lumber is pressure treated.

As I build the framing, I have many variables to measure: the plumb of the posts, the rotation of the posts, the level of the joists, the height of the joists relative to each other. Adjusting each one affects all the others, so it is an iterative process. I want to know when it's good enough, so I can stop iterating. I'm asking here about the plumb

Ok Jay, here it comes!  It is important to make the posts as close to plumb as possible. The closer you are to true plumb, the less stress will be exerted on your mounting fixture. In all honesty, I think the posts are a bit tall and should have been cut to flush down closer to your pad, but then I digress.

Here is a trick to help you plumb and adjust your posts quickly.  Pound a couple of pointed pieces of 2X2 or 2X4 firmly into the ground at 90 degree angles to your post.  Then take the temp support strappings and screw them into your post with a drywall screw. You can now adjust the strapping against the ground stakes until your left and right post sides are perfectly plumb. Screw the strapping into the stake, add a second screw top and bottom and you should have a very secure, perfectly plumb post.

I see in your picture you are using strings.  That is good, but if you can get your hands on a good self-leveling laser, it would make sizing the posts so easy, and give you excellent level  cross checks as you continue to add more posts to the gridwork.  Good Luck Jay


Disposal of hydrochloric acid I used hydrochloric acid and water to remove concrete from my tools (in a plastic bucket) but did not know how dangerous it was and how complicated the disposal process can be--first time using it obviously. It is pretty late at night and there's not much I can do but I am scared to leave it outside overnight uncovered and I don't have a lid for it

You can neutralise the acid by mixing with alkali.  However, be careful.

You will need quite a lot of something like baking powder.  Or if you have any left over - cement powder.

Add a small amount to the acid - it will foam and release gas (Carbon Dioxide).  Don't add too much at once or the bucket will overflow and you will get acid everywhere.

Keep going, small amount at a time until it no longer foams when you add more.  You now have salty water that can be poured down the drain.

I repeat, be careful because of the foaming and you will need a lot of powder.


Unable to remove light fixture because of a wire entry holder Hello,

I'm trying to remove a florescent light fixture but a plastic yellow wire entry holder is preventing the fixture from coming off. (See photo) It looks like a holder that had been crimped with 3 wires in place. Note I'm referring to the yellow plastic holder on the fixture, not the yellow wire nuts.

How can I remove the holder? The wires are tight, so I can't pull the fixture away more than half an inch from the wall with the holder in place.

Looks like you just squeeze together the two yellow tabs with small pliers and the strain relief should pop out. Let me know if it works.


Safety hook on double pole circuit breakers My home was built two years ago, so I would expect everything to have been done up to code. The problem is that I don't know what the metal ring in this photo is. It loops over the double pole circuit breakers, but only if in the off position. When hooked over the circuit breakers, the metal ring appears to prevent them from being pushed into the on position. The problem is, if the circuit breakers are turned on, and the metal ring were to flip over (it's fairly free to rotate), then the circuit breakers are prevented from flipping into the off position. Isn't this a valid safety concern? Yet I am confused because the hooks on these circuit breakers appear to be made to do this as seen by the hooks I have pointed out via green arrows (green speckles follow the loop I am talking about).

I am seeking to learn:

What is this gizmo named?
Is my safety concern valid?

This is a breaker lockoff device
The gizmo on your water heater breaker is a lockoff that's designed to let you turn the breaker off, then attach a padlock with a 1/4" shackle (or a lockout tag with padlock(s) on it), so that you can then lock the padlock, stick the key in your pocket, and be sure that some bozo isn't going to flip the breaker back on while you are servicing the water heater.  Code often requires this when the breaker is the only disconnecting means for the load in question and the breaker box is not visible from where the load is located.
And no, it won't screw up the breaker's ability to trip
Modern circuit breakers are universally trip free (UL489 and related standards require this behavior, even), which means that they will trip properly, no matter what position the handle is held in.  As a result, it is possible (and even required, for breakers feeding fire alarm control panels in larger buildings) to safely lock a breaker on with the appropriate hardware, even, and you do not have to worry about mechanical blockages outside the breaker itself keeping the breaker from tripping.


Maintainability of natural stone vs porcelain floor tile? I am planning a kitchen floor retile project, I'm initially researching tile selection.  I was comparing two tiles and someone at a big box retailer told me that while marble tiles look nicer, they have the disadvantage of being more difficult to maintain.

He said marble tiles are porous, and thus they stain more easily.  They are also more prone to chipping.

How true is this?

As far as staining goes, both the porcelain and the marble (marfil actually, unsure if this matters) have a shiny "polished" finish... And thus they seem smooth and at first glance, non penetrable with liquids, i.e., tea/coffee stains, etc.

The guy at the store is correct. If the marble is not taking on any water now it is because they are sealed, it is a maintenance item, that will need to be resealed every 5 years at the least with heavy traffic, 7-10 years with light traffic with a penetrating sealer. A kitchen floor is definitely heavy traffic.

The porcelain tile is non porous, just the grout will need to be sealed as a maintenance item, according to the same guidelines as mentioned above.

FWIW, both will chip or crack if something heavy enough drops on it.


What kind of grease can be used on outdoor screws to avoid rust I have fixed some screws outside to mount a house number onto masonry.

I feel like I should probably apply some sort of grease or water repellent to avoid rust as they will be exposed to rain frequently.

What kind of grease should I smear over them to avoid any potential rust over time.

I've done some reading and I keep seeing copper or lithium grease mentioned to preserve bolts, are these right for screws or is there something else?

Any coating of grease or other rust inhibitor will wear off over time. The right approach is to use fasteners that are corrosion resistent either due to their material (such as stainless or brass), or are plated (with zinc, chrome, or other durable material).


How to build a sauna? I would build my own DIY sauna, but I can't seem to find extensive information about it. Nor I can find plans to build one. How can I build one?

My father has a lot of home building knowledge, but we've never built a sauna.

I have built a few of them in kit form, they are pretty basic. Cedar finish, cedar slated benches heat and steam source. The info is out there.

This is a website for free plans so it says. Looks like it has a lot of info on it.


Will this 10-foot wide gate design be rigid enough? We've been working at putting a fence around our property and are almost finished. The last part that we have to do is we're adding gates to the end of our driveway.

The fence that we put up is a hogwire fence with wood framing. It looks like this:

However, to keep with the style of the fence, I'd like to build a matching gate. I've seen some ideas online of how to build a large gate that won't sag and came up with this similar design, but I'm still not sure of it: (Front and back views)

I'm hoping to keep the opening as large as possible so that trailers and such can easily enter. We are also having the gap split into two gates and will be using an automatic opener system. Currently I'm looking at having it at 20' wide, so two 10' gates.

The question that I have is primarily, is this design reasonable in hoping that it won't sag? They will both be 10' wide X 4' high. I know that these will be incredibly heavy gates and this just seems unreasonable; but I saw it being done with a 10' wide X 6' high privacy gate, so I would think that these might be a little better off than that.

Also, our driveway is mostly flat and so we'd be able to use wheels if needed, but I'm hoping to avoid that if possible.

Last; I've thought about maybe buying two of the metal farm tube gates instead and just mounting this design (or similar) onto them. Does that sound like a better idea? Or possibly some form of metal support to add to this.

If you were my client and I was taking money for your project, I'd put wood on a metal substructure, have wheels on the ends, and make sure the posts were extremely well stuck in the ground. (You might be able to skimp a little on the post as long as the wheels are in contact with the ground at all points in the arc, but the other two points would be non-negotiable.)


loose leaf on dining room table I have an old table with multiple leaves.  When the leaves are in, on one end of the basic table, the leaf fits tightly.  On the other end, no matter how you push it in, as soon as you let go, the end and the leaf pull away about 1/4".

Does anyone know of some kind of fastener I could mount underneath the inside edge of the table and the leaf to hold them together tighter?

Thanks!


Buzzing sounds when I switch off the electrical socket Is it fine to hear buzzing sounds when switching off power points?

I hear this sound occasionally when I switch off my power points.

Is it fine to hear buzzing sounds when switching off power points?

It suggests something is plugged in and turned on (drawing current) and that maybe the switch contacts are not clean or are pitted.

The buzzing sound is probably arcing as the switch breaks the current. Its a sign of further damage accumulating.

New sockets are cheap enough (less than two cups of coffee) that you could try replacing one and see what effect it has.

At a minimum I would turn the circuit off at the breaker and open up the socket to looks for signs of overheating.


Fireplace sealing to avoid "false chimney" I'm building a new fireplace with a 2cm granite surround (around the firebox opening). This leaves (by design) a 1/2" gap between the back of the granite and the face of the firebox & smoke dome (gap is several inches wide x 1/2" thick).

My question is: To seal off this gap (to avoid a "false chimney" fire hazard), what type of grout should I use? Will the same standard thinset that I use to attach granite-to-fireplace work, or do I need some type of special heat-resistant thinset or mortar?

Or, instead, or in conjunction with, is there a caulk that is suitable for high temperatures that would work in this application?

I would use fire brick mortar. It will hold up to the heat and seal the gap so you won't have the false chimney issue you are concerned about.


How to split 1/2" OD male pipe for sink/dishwasher? (warning, language may be imprecise/wrong)

I'm connecting a dishwasher for the first time. Under the sink I have what I believe is a 1/2" OD male threaded supply line. I guessed this based on the fact that the flexible hose has a label that reads "1/2 OD in to 1/2 FIP out". Please see attached picture.

I thought I would be able to buy a 1/2" inlet to two 3/8" outlets, but my local stores did not carry anything like that. I bought this dual outlet valve, but the fitting was too large for my supply line.

I spoke with two different people at HD, and both of them seemed really confused that my supply line was 1/2" OD. They kept trying to get me to buy the 1/2 FIP again even though I had already tried it.

I tried to buy a 1/2" OD to 1/2" FIP adapter, but couldn't find any at HD.

Thank you.

If you use that valve and your dishwasher starts leaking one day and your replacement takes a few days to arrive, you'll have no hot water to your sink. You should use a tee with a valve on each end of the tee so you can control the water flow independently. In fact, some cities require this. I learned this the hard way by failing my plumbing inspection by using the valve you linked.
The label you describe is kind of confusing. OD is typically used to describe pipe size, not fitting size. 1/2" FIP is used to describe pipe thread size. If 1/2" is indeed too large, maybe you should try a 3/8" sized fitting? Just to be sure, can you update the question with a picture of the label?
Finding copper/brass FIP/MIP fittings is going to be difficult and/or expensive. It might make more sense to buy a cheap cutter and get some shark bite fittings. Or if you want to be adventurous, solder it yourself..


Can you paint linseed oil putty with water based paint? The putty is sealing a window and has has spent three weeks drying. I've heard that you can use water based paint over linseed oil putty, but I want to check.

It was a Selleys linseed oil glaziers putty. The pack says to paint it between 2 and 4 weeks with "house paint" which seems, at the same time, both obvious and uninformative.

Normally you can use latex over oil based products (never the other way around) if they are fully cured and dried. If the putty you are referring to is glazing compound, then you may have to wait a bit longer for it to cure. Glazing is very slow to cure and take paint. If you can still very easily dent it with your fingertip, wait, the solvents have not yet evaporated.  You certainly can test a small area and see how it goes.  However, don't be surprised if you get some peeling in a few months. Oil based paints are hard to find now, but would work better. I don't know what product you used, but there may be some recommendations on the can about painting.


isolated grounds in branch circuits? How does this work with conduit? I recently was told that grounds from different branch circuits in a box need to be isolated.  I'd really like to understand the purpose of this. It doesn't really seem like it would contribute to either function or safety.
This also seems like it would imply that metallic conduit, which must be grounded can only have one branch circuit, regardless of size.
Now I know the latter isn't true, because NEC 250.122(C) gives an example of doing just that.  Is there any way of explaining this discrepancy, or is this just one of those things I just have to accept at face value regardless of whether it makes sense.
NEC 250.122(C):

(C) Multiple Circuits. Where a single equipment grounding conductor is run with multiple circuits in the same raceway, cable, or cable tray, it shall be sized for the largest overcurrent device protecting conductors in the raceway, cable, or cable tray. Equipment grounding conductors installed in cable trays shall meet the minimum requirements of 392.10(B)(1)(c).

I'll bet what you heard about isolating was about the grounded wire, which is what we normally refer to as the neutral wire. See:
Grounded vs. Grounding
for a more complete explanation.
Neutral wires indeed need to be kept separate for different circuits in the same box. The exception, sort of, is an MWBC where one neutral actually serves two different hots on a pair of circuit breakers. Mixing neutrals can result in a situation where a neutral gets overloaded because another neutral connection broke, where if they were not mixed that circuit would instead go dead. Plus mixing neutrals will not work with GFCI breakers.
The grounding wires, aka "the ground", can be mixed without any problem.


Using 12/3 wire to run a different outlets in a kitchen I am running 12/3 wire into 3 kitchen outlets. In my panel box I had an electican deciate two 20amp breakers for the red hot wire and black hot wire. I have connected the black wire to 2 different outlets and are working great. I need another outlet using the red hot wire. So, my question is I know that the red is hot so do I just connect it to the other reds and continue my circuit to the third outlet? Then do I also connect to the 2nd outlet white and neutral wires on the last outlet to finish the circuit?

You have a multi wire branch circuit. You are correct that the reds go to 1 set of outlets with the white and ground from the point you brought the black, white & ground. The first outlet in each string should be a GFCI for all counter top outlets 2014 NEC 210.8.A.6. The handles should be tied with a listed snap on tie or a double pole breaker to be fully code compliant.


Light switch no power when on I have this bathroom light switch, when I turned it on, I tested power between red and black wire, there is no power

If I turned it off, there is power red/black line

How does it work exactly? I don’t understand this

UPDATE 1

According to answers below, this is a 3-way switch but it unnecessary because there is only one switch for the bathroom light. My goal is to move this switch to a different location. Right now it is OUTSIDE the bathroom. I want to turn it inside the bathroom. So should I continue to use this same switch and the way it is routed? Or should I take advantage of this and re-wire it?

What you're trying to do isn't going to work

Judging by the extra Romex freshly brought into this box, it looks like you're trying to power an additional lamp or outlet from here, and specifically, from this here switch.

Not gonna happen.  At least not the way you intend.

However, a new thing changes the picture: Smart switches.  There's good chance we can save this.

If you can pull the other switch out, and get us some photos of what's going on in the back of the box, we will be able to advise.

Why you can't just pull wire to any old place

In the future, don't buy anything or pull the wire until you've figured out the circuit :)

Your new branch needs "always-hot" and "neutral" if it's an outlet, or "switched-hot" and "neutral" if it's a lamp or fan.  You can't just assume those are going to exist in any given location.

That switch is a 3-way switch, as HP discusses.  In 3-way circuits, the downside is they almost never have the 2 wires you need in any given switch location.  The upside is, they have extra wires, and with smart switches, we can take advantage of that.


How many vent stacks should a house have? I just purchased a 1948 pier-and-beam in Austin. The pest control guy came to deal with rats, and asked me to locate my vent stacks. We seem to have one for the washing machine, but none is visible for either the bathroom sink or the kitchen sink.

Is this normal? Should I be looking for a vent stack terminating in the attic, perhaps under the ceiling insulation? There's definitely an unpleasant smell in the house from time to time.

Both the bathroom and the kitchen are original (though the bathroom has been updated).

It may also be worth noting that there's a guesthouse, which I believe utilizes a sump pump to deal with its sewage. The guesthouse has its own stack pipe.

Most homes will merge the vent pipes as they go up the walls so that you only have one vent exiting the roof. All vents need to slope upwards, so the guest house couldn't run the vent underground to use the vent stack in your home.

That said, if you notice that drain lines are gurgling after the water goes down (indicating suction) or are slow to drain but have no clogs (indicating it's trying to overcome the air pressure in the lines) then there may be a blockage in the vent or it may not be properly installed.

Note that for some situations, you can also have an air admittance valve to provide a one way vent (fresh air can get sucked in, but sewer gases cannot escape), which allows you to vent plumbing in a kitchen island or other location that cannot go up and out the roof.

For the odd smell, it's difficult to diagnose over the internet, but it could be a dry trap, a failed wax seal under the toilet, or a dead animal in an exhaust vent or inside a wall.


A/C compressor connection to the house not sealed anymore. How do I fix it? The A/C compressor that sits outside our home had a sealed connection to the house (pretty new, 3 years old), and it seems a "gasket" was created with silicone.  However, the soil underneath the compressor started to shift a bit, and so the compressor now sits slighly farther from the house.  We have fixed that, so it's not moving anymore, but now the A/C hoses connecting to the house look like this:

Should I simply put some duct tape around it to seal it again?  Should I remove the silicon and create a larger silicone gasket?  Not sure if this is a big deal, and we haven't seen any unwanted side effects, but I want to avoid any long-term problems.

Remove the silicone pieces and trim the grey rubber back and then use Great Stuff to fill in the voids and insulate the pipes. You've got a pretty good opening there and you don't want any critters crawling in there.


Standing water at back of shower need suggestions Contractor converted bathtub to shower, finished yesterday, shower has standing water at back and middle of shower after use. What are possible solutions.

The short answer

As others have said in comments, the slope of the shower - called the "fall" - is the most fundamental thing to get right.  You need a gentle fall from the edges of the shower to the drain on all four sides, so that any water immediately flows to the drain.  This is "bathroom installation 101", and an installer who does not know this should not be licenced to operate.

I'm sure you won't want to hear this, but the solution is likely to require a contractor removing the shower, ripping up the tiles, re-levelling the floor to apply the correct fall, re-tiling and then reinstalling the shower.  Worse, if the contractor was really dodgy, you may find that the waterproofing on the walls & floor is substandard, the implications of which are serious.

It's essential that you do not pay the contractor (if you haven't done so already) and that you let them know that you will take legal action if they do not fix it. The bad news is that cost of the rework will now be several times the cost of original work.

The longer answer

From a "doing" point of view, this is what needs to happen if it is done properly.

If the shower frame was installed after the tiles went down (as would be the case with a frameless shower), then the glass and frame need to be taken out and put gently into another room.
Next, all the tiles on the shower floor need to be chiselled out.  Worse, if the wall tiles were laid down after the floor tiles, then the bottom one or two rows of wall tiles need to come off before the floor tiles.
Then the precise edges of the shower frame need to be marked perfectly on the floor, so there is no ambiguity about precisely where the high points need to be.
Next, a competent floor-leveller needs to use re-level the floor under the shower, so that it falls correctly down to the drain on all sides.  This could end up an even bigger job, because if the level of the shower is ends up higher than the surrounding bathroom and there is no drain in the rest of the bathroom, then the existing ardit may need to be jack-hammered up before new ardit is laid.
Then the floor tiles need to be re-laid.  Depending on how well the ardit work was done at the previous step, there may also be a need to add some extra slope with the tiles (e.g. by adding thicker blobs of glue to the outside edges of the tiles near the frame and less glue immediately near the drain).
Finally, the wall tiles and shower need to be put back.

I note further that an installer who hasn't installed the correct slope may also have taken short-cuts in other areas.  For instance, were the shower walls and floor fully water-proofed?

If not, you have an even bigger problem on your hands.  A bath is obviously water-proof, but a shower is not: grout is porous and therefore water will seep into the walls and floor every time you shower.  The problem will be especially bad if water is pooling on the shower tiles instead of flowing down the drain, because it will soak through the grout and then into the sub-floor and eventually into other rooms as well.

Alternatives??

Notwithstanding all the bad news above, depending on what exactly what done by the contractor, there may be short-cuts to fix the problem.  As someone suggested in the comments, more information about the installation would help us answer your problem.

Please note that I'm not a builder, just a person who has done renovations myself (including a very recent complete bathroom demolition & rebuild).


Should the cord on my miter saw have a grounding wire and plug? I have inherited a chop saw, hooray, but it only has 2 prongs on it’s power cord. Is it safe to use? Is there a way to ground it? Thanks!

In a two-prong device, if there is a short from the hot wire coming in from the wall to the metal housing of the device, the metal housing becomes hot too, which is a shock hazard.

The third (earth ground) prong simply returns current to earth in case of a such a short so the housing doesn't become hot. If this kind of short happens and you have a third prong, you'll pull lots of current momentarily from the wall through the housing down to earth ground at the moment the short occurs and trip the breaker. If you don't have a third prong, you become the conduit between the hot housing and earth ground when you touch the device, which could be long after the short mechanically has occurred, since the short is "waiting" for a return path -- i.e. someone touching the housing.

Anyway, if the saw has a metal housing, definitely replace the cord. If the saw has a plastic housing, the risk is lower. You can add an earth ground by replacing the power chord and tying the earth ground prong to the metal inside the unit. I usually do this with a ring lug if I can find something threaded inside the chassis. You could also clip the metal housing to something else nearby that is earth grounded (three-pronged), since earth grounds should, by definition, all sit at the same voltage.