What sizes of DWV pipe are commonly used for (very) small residential homes? One of the DIY projects I sometimes contemplate is replacing the ~45 year old galvanized steel drain pipe in my house with PVC DWV pipe and fittings. There is at least one slow, dipping leak I currently have a bucket underneath. There are also other connections which have been "repaired" by wrapping them with black electrician's (?) tape. My feeling is that even I could do a better job than what is there now.
One of the things I thought I would do if I ever actually did this was use slightly larger pipe. However, while browsing the big box store websites, I got the impression that the most common DWV pipe they seem to offer is either 1 1/2" or smaller and 3" or larger. In particular, 2" PVC … the next step up from 1 1/2" pipe … doesn't seem to be offered in the bulk 10' lengths which the other diameters are available in.
Is my impression about this correct or am I just looking in all the wrong ways? If it is true that 2" is not as popular a flavor then, well, why would that be the case? What (obvious?) aspect about how DWV installations "work" am I not understanding/grasping?
Below is some additional background about my home for context.
My understanding is that most of the plumbing & electric in my house was put in by the previous owner when it was built in ~1950. The only drains in the house are for

The kitchen sink.
The bathroom sink.
The shower/bath tub.
The toilet.

The toilet sits right over the main outlet pipe leading to the septic, so there is essentially no additional drain pipe for it. All of the other drains feed into this main septic outlet underneath the toilet. There is only 1 vent pipe and it also connects to this septic outlet pipe.
The other drain pipe consists of about 32' of galvanized steel pipe.
The main drain line is (unvented) 1 1/2" pipe from the kitchen sink's trap to outlet to the septic. The path is ~6' from the trap to a "T" with a plug on one end. The other end of the "T" runs ~13' to reach the outlet to the septic.
The bathtub drain has a straight run of about 5' of 1 1/2" pipe into another "T" into the 1 1/2" to the septic outlet.
About 8' feet of 1 1/4" pipe is used to connect the bathroom sink to the 1 1/2" pipe.
Basically, because the setup is not that big and most of it can be directly accessed, every time I consider making a spot fix … during which I may break some other weak spot … it seems to make more sense to just yank most of the existing pipe and replace it.

Find a better store, if the ones you are going to don't have 2" PVC in full sticks (or possibly look higher up in the store you are in, and get someone to drag it down.)

In MY house, the only place you'll find 1-1/2 or 1-1/4" is the tailpieces on the sinks - as soon as it hits pipe, it goes up to 2", because it's not that much more expensive and it greatly reduces the odds of having any issue with it. I don't recall having any trouble finding it in full sticks. The main line is 4" (not 3") for the same reason. Builders looking to squeeze maximum profit don't do that sort of thing, but builders who plan to live in the building for a while sometimes do.

In retrofitting, you might need to use 1-1/2" due to space constraints. In any case, if you are redoing the pipes, you should probably bring the venting up to current code while you are at it.


Replacing light fixture UK unable to determine which wire is which We had our kitchen redone within the last year, part of that was adding a new light fitting which was to be replaced later in the year.

That time is now, I've just taken the old one off which has seemingly the same connections, but after plugging into what I thought was the exact same position, our power just keeps tripping.

I have been putting the Blue and Brown the the Neutral on the fitting, the middle in the Earth, and the Black and Red in the Live.

Could anyone suggest what  I am doing wrong?

Stupidly, I didn't take a photo of the light fitting before I removed it so I'm not sure if the combination has been mixed up.

Thanks.

One of those cables goes to a switch loop. You need to find out which. Open up the switch that controls this light and see what wire colours it has.

If the brown and blue (new colours) are the switch then connect

red to brown (which takes live to the switch)
blue to the "L" terminal of the the light - blue is switched live so you must  put red tape around the blue wire.
black to the "N" terminal of the light (neutral)
put a green/yellow sleeve over the bare earth wires and connect them using an approved connector. If the lamp has metal parts, they need to be connected to these earths too. The middle terminal in your second photo would probably be intended for this. Check for continuity between all metal parts and the earth wires.

UK Wiring colours

              Old       New
 Live         Red       Brown
 Neutral      Black     Blue


How to make sure a dampen floor and wall is caused by a leaking pipe? I got damp tiles on the floor in my bathroom.
I also noticed rising damp on tiles fixed to a wall from exterior side of the bathroom.

Pictures:

I think it is a leaking pipe installed bellow the tiles but not 100% sure.
As I remeber the pipe was installed somewhere close to the area where I see the damp so the leakage is likely to be true but....

From the other side of a coin just before the problem shows up we were cleaning the patio with a preasure cleaner and it was very extensive cleaning as we were preparing it for sealing/painting job.
The patio is a cross of the bathroom wall and I belive high preasure pushed a lot of water in to the concrete below the tiles as they are not not well grouted, so this could be the other case.

Leaking toilet output could be a case as well.

To check posible pipe leak I have done simple test with a water meter like this:

1) Checked that all outside connection (shower, sinks, garden outputs) are not leaking.
2) Closed all outgoing water sources and took a picture of a meter at that stage.
3) Than, after 40 min I took another picture of the meter.

As you can see on the image bellow the gauge has moved sligtly in this 40 min. This would indicate water loss.

I'm not sure how to read the gauge, what exactly is the loss and what it could mean.

What further steps to take to make sure whats wrong?

Thank you.

I'm adding an update with a third measurement following 5 hours after the send one. In my view they all show nearly 1 liter leaking a day. Could someone validate please?

There's no way to positively say whether it's the pipe or the pressure washer.  The water meter readings may, or may not, be meaningful - that water could be going somewhere legitimate as Daniel Grissom said, and it's a very small amount of water.  To check the pipe you'll have to get access to it, which means tearing up the tile.  So what's more likely - a pipe started leaking at the same time that you pressure washed the patio, or that water got into the wall while you were pressure washing?  If it was me, I'd get several fans blowing on the damp area for a few days to see if it drys up.  If it makes no difference after a week, then maybe you need to dig into the tile.


Plumbing utility sink into washing machine with no vent So I currently have a washing machine that has its hose running into a 2" standpipe that is coming out of my basement floor.  A humidifier hose and AC hose also squeezes into that standpipe and it's pretty tight and janky looking.   I'm trying to clean everything up with proper piping, install a laundry box and also a utility sink.

There is no vent or additional plumbing nearby that is easily accessible.

The standpipe is on the left, machine in the middle and the sink would be on the right.   Can I have a single PVC pipe that connects the sink to the machine that then connects to the standpipe?   Do I need a mechanical vent for it to work?   It all seemed to work fine before but I am sure it wasn't to code (Toronto).  What is the best way to connect the humidifier and AC to the same pipe?   Should I have individual connections piped to the standpipe?

Here's the standpipe on the left with humidifier and washer draining into it:

Diagram of the current setup:

Proposed setup - sink on right and washer on left, draining into standpipe.

Or here's another proposal.   My understanding is I need to swap the sink wye and put it above the washer so there's no chance of backing up the utility sink.

What considerations should I be making with regards to venting, angles and heights?  Any other considerations?

Thank you for your help!

Don't stack the san tee's on top of each other like in your second drawing. As the top fixture drains it can create a vacuum inside the Lower trap  arm and siphon the water from the trap allowing sewer gas into the room. What you want to do instead is use an upside down wye or "Y" fitting (so there is two openings on top and one on the bottom)  with a 45° elbow on the branch that isn't completely vertical.   You should end up with what looks like  a lower case h but flipped upside down. Now that you have two separate vertical lines you can add your san tees on top of each, then run your drain line to your sink,  and the other can serve the laundry.

And as for the vents.   On top of your san teesRun the pipe up higher than the flood rim of either fixture (the point where water will overflow), so either top of sink or washer whichever Is higher.  Put a 90° elbow on one and point it towards the other pipe.  Take one more san tee but flip it opposite direction (the middle hub/opening should curve upwards not down) put that on your other pipe pointed at your 90° , tie them together.   Add another small piece of pipe to the top and a AAV Or studor vent on that and your all set.

The condensate and air conditioner you can run to the corner of the sink,  or you could put another upside down wye & 45° on the laundry standpipe/drain ABOVE THE P TRAP and run them into that.

In that situation they will act as a sort of trap primer.  Not that you would need one there.   But the important thing about those two lines are that they must have a 2" air gap.  Meaning you can't tie them directly into a sanitary sewer line.  They have to be an indirect drain.

BUT*
This has all been with the assumption that your local authority having jurisdiction uses these Uniform Plumbing Code.  I can't speak for IPC however.

And for any of this to be true  you would need to know if the stand pipe has a p trap below the floor or not.     If it does you shouldn't be adding any fixtures to that stand pipe.


Fire alarm has 3 black / white wires, 1 red? I have a newish room (built in 2008, New York), and the smoke alarm had a wiring setup I am confused about. It has 3 black wires, 3 white wires, and 1 red wire. See attached picture.

Anyone know why there are so many wires? Shouldn't alarms just need 1 black/white? Not sure what the red was for.

I would refer to the original alarm in there, but the owner told me they don't remember how it was setup when they took it down.

Related, there are two wall switches in the room that don't seem to control anything - I am now suspicious that they go to this box, but no idea why you would want 2 wall switches going to the same box that has a smoke alarm?

Thanks

The red is probably the comm conductor for linked units. It is a bit odd that there's only one, but it could simply be the first in the chain. Without knowing the entire circuit layout I can't speculate further.

The extra blacks and whites are probably part of a lighting circuit on the same breaker. To connect your alarm you'd pigtail from each color.

Your mystery switches could be for switched outlets. Check for half-switched outlets where you'd expect end tables, for example.


How to safely chip away at a tile to make room I need to install a shower against a tiled wall.
I have 2 issues :

I need to safely remove a tiny bit of the tile, to give me more access to the water outlet of the pipe. What tool and method should I use to avoid breaking the whole tile?

Behind the tile, there is some cement/concrete (I think). I need to remove it to have access to the water outlet, but without breaking everything (the tool I use will be very close to the tile). Should I use a drill or a chisel and hammer?

You should use an abrasive grinding tool with a relatively fine grit or tooth, not a cutting tool. You don't want anything that can catch the tile and shatter it, and you want to operate at a fairly high rpm to reduce chatter and grab.
Apply pressure parallel to the face of the tile only--don't push inward or outward or you risk spalling the face of the tile. Keep the tool square with the wall.
High speed, low pressure. That's the name of the game.


What can I do with a buried copper gas line? When we bought our house in 2005 we were advised by our utility company that there was a gas line on the property. We discovered it is at the bottom of an old BBQ grill that apparently didn't work and was turned into a planter, overflowing with ivy.

One day I came outside to find the grill/planter had fallen over exposing the brass or copper gas tubing.

What can I do with this now? It appears copper is no longer considered stable for gas so I suppose I can't use it for a fire pit.

Suggestions? i have sent an email to the utility company asking for advice. The copper is now bent because the planter fell.

Thanks in advance!

M

In our neighborhood of 1970 built tract houses some homeowners added copper lines to a grill in back and a gas light front. The copper lines are invariably  connected to a saddle valve on the black iron gas service line above ground just before it enters the structure. (Fortunately no previous owner of our house added this.)

Some years back I helped a neighbor whose grill was non functional, dilapidated and whose gas light rusted out at the bottom and fell over. I made sure the saddle valve was off at the supply and I removed both the grill and the gas light. I cut off the copper lines below ground and flattened the copper tubing for 6" or so to seal it, then buried it. So there is 100 ft or more of abandoned copper tubing in the ground still connected to the gas service line.


Screws breaking through drywall paper One of the several scenarios in which a screw doesn't form a nice and tight seal on drywall paper just below the surface is if a joist/stud is not in the same level as the adjacent two and there is a gap between it and the drywall. As you're driving the screw to just below the paper, the paper breaks and the screw goes in too deep, resulting in less clamping force than a snug screw.

Q1: Is a screw like this completely useless? If not completely, how useless is it?

Q2: What percentage of screws per sheet are safe to be like this?

P.S.: I would appreciate no perfectionist type responses like "why do you have uneven joists" and such. I'm remodeling a 110 yr old house and I'm not replacing joists, some of which have sagged. I sister what I can but some require planing, and planing ceiling joists and having sawdust fall over me is my definition of misery. So I'm trying to be in an acceptable ballpark. Thanks

It depends how far in. Ideally you want it less than 1/8" in. Within 1/2" drywall, that's a decent amount. If you get more than 1/4" in you run the risk of cracking the gypsum underneath and not providing the adhesion.
I don't know about a percentage. I would drive another screw nearby if you over-drive one. Leave both in.


What can be safely attached to a gas furnace cabinet? The gas furnace in my house is in my laundry room about 3 inches from a stacked washer and dryer.
As such, my laundry room is short on space, so I had the thought I could add some organization by using the furnace itself. But I'm not sure if this is safe.
A few things I've thought about attaching to or placing on the furnace:

magnetic racks that can hold a few pounds
a box of wool dryer balls
cleaning agents (bleach, wood cleaner, 409, etc)
cleaning tools (broom, mop, etc)
box of dryer sheets

What I'm looking to find out:

How safe is it for these items to be placed on or attached to the furnace?
Are any of these items at risk of causing a fire during normal operation of the heating part of the system?
Will these items (especially the magnets) interfere with the furnace?
For future reference, what kinds of materials and items should absolutely not be attached?

Gas Furnace Info: Carrier Performance Boost 90

The external surfaces of the furnace and ductwork are not hot enough to be a fire hazard with the items you listed. As we don’t know if this is a newer sealed combustion system or older gas vented system you would need to stay away from a vent they can be hot.
I would not hang heavy items like gallons of anything even if magnets could hold them the duct’s are not designed for this but light loads I don’t see a problem.
I probably would not put even 409 or any chemicals there I had one customer that used the main trunk line to the registers as a shelf. The heat cool cycles caused spray bottles to dribble when the heat was running the air in the bottles expanded dribbled on the duct and one of the bottles had a cleaner  that dissolved the galvanized coating and it started rusting. (My guess it was a slightly acidic cleaner as even vinegar will dissolve galvanized coatings).
I was able to clean the rust and use cold galvanizing spray to stop the rust she then put the stuff on a raised tray and that stopped the dribbling.
You don’t want stuff dribbling down the side.
I don’t see a problem with dryer balls anti static sheets or hanging a broom by magnets and would not expect any problems because of the magnets.


How could the location of a radon abatement hole impact its effectiveness? The radon level in my partially finished basement is from 8 to 11 pCi/L. I'm looking to have this installed professionally by contractors and the recommendation so far is to create the hole near the outside wall of the house. It seems that the recommendation is being made to make the install easier but I'm uncertain if it's most effective. I do not mind if carpet or drywall needs to be torn up.

Would I see an larger decrease in radon levels if the abatement hole was placed in the middle of the basement rather than in the corner or at the side of the house?

It's a simple matter of airflow, so the answer partly depends on the collection mechanism.

If your system will rely on underslab media, such as washed rock or plain gravel soil, flow reduces exponentially with distance from the vacuum source. For this reason a centrally-located port would be most effective, by far. An alternative would be to have multiple peripherally-located ports.

If your system will be a sealed drain tile type, it won't matter as much. Theoretically, vacuum will be roughly equivalent at all points in the pipe, and will therefore draw uniformly on the adjacent medium. In a large or complex tile layout some reduction in vacuum could be expected at remote points, but a true central port location is probably not an option as drain tile is typically installed at the perimeter of a foundation.

Leaks in the system can dramatically reduce effectiveness on a localized or system-wide basis, of course.


How to cool tank water in summer? My home is supplied water from a well, that gets stored in a roof-top tank. The problem is that during these summer days (45°C), the stored water heats up and gets scalding hot. Its impossible to shower or to even to wash my hands!

I need a solution to this. Is there something like a water chiller which can cool the water as it flows into the house. I know there are whole house tankless water heaters, I basically need something that does the reverse job of that.

An aquarium chiller is meant to cool down a tank of water. You will find different types for different sizes of tanks and how much they need to cool the the tank.

However you may get a cheaper cooling effect by simply putting the tank in the shade by for example building a simple shed around it. This will prevent the direct heating from the sun.


Painting over bright color with Kilz and single-coat of one-coat paint: overkill? Underkill? We are expecting to close on a new house Friday, and my out-of-state father-in-law will be there for the weekend only to help us paint a couple of bedrooms.  The rooms are bright colors now, and we want to replace the bright colors with a light gray on the wall and a white on the wainscoting.  We intend to use a coat of Kilz primer, and he is recommending we use an expensive one-coat paint (Behr Marquee) on top of it.  Will a single coat probably suffice?  Is it overkill to use an expensive paint+primer on top of a primer?

We will be painting with semi-gloss, and I believe that is what is on the walls already.

I agree on using the primer first. However, the combination primer/paint may be overkill. I would plan for 1 coat of primer and two coats of regular paint, as it is tough for the average DIYer to get full coverage with one coat of paint.


how do i flatten my hardwood? I have a 60 year old house and the original hardwood floors have been covered for at least 25 years and the slats are cupped with the edges of each slat being higher than the center of the slat. What is the best way to sand these floors smooth so that i may put either another layer of hard woods or vinyl slats over the top of these existing floors?

Worst case scenario: remove the flooring.

Medium damage throughout: Lay down 3/8" plywood over it, first replacing heavily damaged areas.

Every board is slightly cupped: Have it professionally sanded and refinished. Upright floor sanders can be rented but they are not for novices. A random orbit sander would get it done... eventually.


Is this gap between foundation and siding supposed to be here? If not what should I fill it with? I have hundreds of crickets in my basement every fall. I see them crawling up my foundation so when I looked underneath the siding I see this. There is what looks like ripped plastic paper but then just a large gap into my basement around the entire house.

Is there supposed to be a direct entrance into my basement under the siding? (Maybe for moisture reasons or something?) If not what should I fill this with. Would like to do it once but do it right.

If the gap is supposed to be there could I install a mesh like this to help with the problem?

You can buy rolls of 'bottle or bristle brush' type material in different diameters. Essentially plastic bristles with a twisted wire core, simply cut to length and pushed up into place.

Originally designed to deter mice, but it'd work for crickets just as well.


toilet is continually clogged Appreciate if someone can tell by not providing good sealing of the toilet bowl "s" trap pipe going into the floor affects the flushing strength / clogging or just leads to escape of gases

If the wax seal is misaligned enough it could potentially lead to clogging, though I would also expect water on the floor if that is the case.

If the toilet was just seated poorly, then your risks are escape of gas and escape of sewage.

Frequent clogs are usually caused by an obstruction, either in the toilet itself or downstream.  Venting problems usually manifest as gurgling or slow draining versus a complete clog.


Should I synchronize programmable dual zone thermostats to come on at the same time? I have two zones in my house and both have programmable thermostats. The temp in the house is set to 18 degrees while I am at work all day, and when I return it is programmed to 21 degrees. When I return home should I program both thermostats to come on at the same time since the furnace is on anyway for one thermostat.

Like Ecnerwal says in the comments, it probably doesn't matter much, but knowing more about your system and climate would help -- recovery time would be very different if the ambient temperature is zero or 15 degrees.   Depending on your system, if only one zone is calling for heat, it may come up to temperature a bit faster than if two are (especially if it's a forced hot air system); if one zone is more important to be warm when you return, set that one to come on first.

More importantly, you might consider whether you need both zones at 21 when you return -- perhaps one zone could stay cooler until later in the evening; the savings from delaying that increase will probably be more than any difference in how you raise both zones.


How can I repair damaged plaster when I come to repaint? I have a couple of problems with the plaster of my house, and when it comes to repainting, I want to try to fix them.
I've watched some youtube videos, and done a lot of googling, and although my search has produced a variety of products that I can use, I've had conflicting information and also such a wide range of products, that I am at a loss of how to proceed. It's also quite hard to find exact details of procedures, as there are many topics on what to use, but it's unclear how to apply.
photographs of problem areas are below.
Some are caused by penetrating damp, which is now fixed.
For the green, my plan was to try to sand the bumps away, and then apply something like "Polycell Ready Mixed Plaster Repair".
It's unclear if I have to remove the paint first, or how to even remove the paint as it's not really flaking. I was basically going to slap some on, and buy one of those trowels and try to smooth it as flat as possible, then when it is dry, sand it and paint it (first adding diluted paint as a primer).
For the yellow, I am really not sure, perhaps I can do the same thing?
The white at the bottom I really have no idea, I suppose again, the same thing but I am not sure how to get a clean edge.
I have read things about pva glue, stain block, joint compound (?) and all kinds of stuff, so I am overwhelmed. I am a total DIY beginner, the best I've done so far is just sanding and painting.
Any advice would be welcome.

Here are some general guidelines. This sort of work needn't be complex.

Loose paint and plaster must be removed. Repairs made over them are likely to fail.
Securely-bonded paint does not need to be removed.
Glossy surfaces should be scuffed or etched, or should have a bonding primer applied before repairs.
If moisture isn't a common problem, standard joint compound (drywall mud) is a fine material for skimming. It's inexpensive, easy to use, and easy to sand.
If moisture occurs regularly, use a cement-based setting type joint compound or powdered plaster repair mix. This cures rather than simply drying and resists moisture damage much better.
Prime all patched areas to seal the surface in preparation for paint. Ideally, prime the entire wall for best uniformity.


Water heater on concrete--should I build a platform? How much heat loss in winter? I don't know if that title is the best way to phrase the question.

It is winter(ish) now, and I swear the hot water just doesn't last as long as it does in, say, September. The water heater tank is insulated with the standard factory insulation. The house is heated, of course. But I know the concrete slab is colder now than it was a couple of months ago.

I'm wondering about building a short wood platform (pressure treated 2x4's, 3/4" plywood) to put the water heater on. But I'm not crazy about taking the time to drain the tank and move it, and cut and resolder the pipes. I mean, I certainly can, I just don't know if it will end up being worth the effort.

Any thoughts? Does anybody think the water heater is losing substantial heat through the bottom into that big concrete heatsink it's sitting on?

Probably won't make any noticeable difference.

Normally the bottom of the water tank portion is insulated if electric, and not remotely in contact with the floor if fuel-fired (there's a burner between the bottom of the tank and the floor, and a substantial amount of space taken up by the burner assembly.) I'd save the idea until you were replacing the water heater, if you want to do it.

More likely that your inlet water temperature is lower, as well as heat loss from pipes being higher. While deep well water is fairly invariant, city and other shallow-piped water systems do vary quite a bit seasonally.


Is it OK to liquid nail drywall in a hard-to-reach corner? I need to drywall around an 8" air spiral pipe coming out of a wall at a 45 deg angle and there is very little room on the side between it and the wall the pipe runs parallel to.  So it is very very hard to screw or nail the drywall because there is simply no room to reach with a screwdriver/hammer/drill.

Are there any issues with affixing that piece with liquid nails?  I was going to apply some liquid nail on the framing behind and basically glue the drywall.

Yes you can.  I have my guys use Liquid Nails for ceilings.  We still add screws but not really sure you HAVE TO.  Definitely nothing wrong with using the correct adhesive for a few studs on a piece of drywall.


What is causing my gas water heater to make a high pitched noise? I woke up two mornings ago to water that was colder than usual, so.. I naturally went to check the water heater and the pilot was out, the pilot light has never went out in the 4 years- almost 5 I've owned it. I turned it back on and all was fine until that night, I noticed a high pitched squealing noise like pressure escaping a tiny hole.. I was pretty tired so I waited until the next morning to check it out. When I went back to finally find the source of the noise the next morning, I noticed it was louder than it was that night. I turned the pilot light off first thing, and the noise immediately stopped. As soon as I press the ignition to turn it back on the noise starts again and doesn't stop until the pilot is off.

I have no idea what could be causing it, is it normal ageing or is there a cause for concern? I've pretty much left it like that the past few days and the intensity of the sound hasn't changed but it's becoming annoying real fast.

It sounds like either a dirty pilot light or your the flame may be getting into your air venturi. I would have the burner pulled and clean both the pilot burner and main burner including venturi tube.


Is my two-way switch installation easily fixable? I'm trying to fix an uncompleted installation of a two-way switch.

One switch, the light and all the wiring have been installed by someone else, with whom we can't have any contact soon.

I bought the second switch and tried to install it. I blindly tried different combinations and had those results:

With some wire combinations, it didn't work at all.
With some others, it worked 3/4 times, but in some positions, one switch didn't work until I reached the other one.
When bridging all wires of the second switch together, the first switch controlled the lamp (ON/OFF) -- but I now doubt it, maybe some of them wasn't wired correctly?

In no case was it working fully as expected, but I didn't try all combinations.

I have a basic understanding of the way it should work when everything is wired correctly.

I tried to systematically understand the consequences of inverting wires in all combinations, and came to the conclusion that it should either

work as expected
work 3/4 times
everything is shortcut and the light is always on

So, if I understand correctly, the wiring is wrong. The colors seem random and non-standard, so I can't rely on that.

Is this correct? Is this something I can easily fix?

UPDATE: each switch is connected to 3 wires coming out of the wall.

UPDATE 2: I'm living in Belgium, but the colors of the wires in my walls don't seem to be the national, or even less the European ones ;-)

Look at the other switch; there should be 1 coming in; a black live, and 2 travelers black and red or black and labeled black coming out. The neutral will just be pigtailed. If there is just a single switched live going out then you will need to run an extra wire to the other switch.

To make a single switch into 2 you need an extra traveler (switched live) between the switches.


Turning light on turns power to fire alarm off I have a ceiling fan connected to a two way switch. When I turn the ceiling fan/light on, the power to the hard wired smoke detector is cut off, whereas turning the fan/light off returns power to the smoke detector. I am stumped. Any ideas?

Thank you in advance for your responses!

Alex

Updated solution per comment:

The fire alarm should not be connected to a switch at all. It's likely that it is connected to the same switch as the light but with the wires reversed. The solution would be to remove the fire alarm black & white wires from the switch and splice them in the box to the cable that feeds the switch, but before it "hits" the switch.

Old answer saved for posterity... i.e. it may help someone else:

There's so many ways to get into this situation and it's impossible to guess which one you're in but: Take a look at this site: https://www.homeimprovementweb.com/information/how-to/three-way-switch.htm It contains diagrams for all the different ways of wiring a light with two switches. Something you will notice about the diagrams is that there is no other load (device that consumes electricity) in the diagram.

In your situation a separate load, the fire alarm, was introduced into the two-switch system and it should not be. In each diagram you will see a section that says something like From power source. This is where the electricity is coming in and this is where your fire alarm should be spliced in. i.e. The fire alarm should be connecting to the power supply before the two-switch system.

Now, how to fix this? If you're lucky the electrical box that feeds the fire alarm will have two separate three-wire cables running through it and it just happens to be spliced into the wrong one. In this case you just need to re-splice. But it's also possible that there is no 2nd wire in which case you will need to splice into whichever light-switch box (or possibly the fan box) and run a three-wire cable to your fire alarm. Yes, this could be just as painful as it sounds. If you have drywall up you may need to get into the wall to thread the cable between the boxes and then have to repair and paint...

In any case, good luck.

P.S. It's also possible that the power supply is coming into this system from the fan's electrical box. If this is the case then your worst case (having to bust through the drywall) becomes a little easier.

Here's a sample diagram (modified from option #1 of the web site given above) of where a separate cable may be spliced in so it doesn't behave the way you're describing.


How can I fix this toilet flange? So I'm in the middle of a bathroom remodel and I was having problem removing some damaged flooring around the toilet flange and ended up taking a reciprocating saw to the lip of the flange to make it easier.  I thought i would just replace the whole thing so it wouldn't be a big deal.  Turns out under the flooring is a series of elbows butted together so there is nowhere I can cut and replace an elbow.  Is there anyway to salvage this toilet flange so I don't have to remove and redo everything pictured (the other side of the Y leads to another toilet in an adjacent bathroom)?  It's a 3in drain pipe.  I'm wondering if it would be possible to set a 4in flange right on top (after cleaning up the rim) or if there is some other product that will do essentially the same thing.

-edit- having problems uploading pictures from my phone.  The top of the flange is basically gone.  It is plastic.

-edit2- added pics finally

Your pictures are showing that it will be necessary to remove the existing drain lines up to the place where there is free pipe to cut into thus allow gluing in a new coupling. It will unlikely for there to be a decent way to fix this by any other means. Any type of cobbled together "fix" is always going to be a potential weak spot in the system ripe for failure.

It is possible to buy special reamers that can be used to remove pipe inside of a coupling joint so that a new pipe or fitting can be glued into there. However I am not sure such tools are available for your size of drain line. These tools also require good "straight in" access to be able to be used. It might be an option for you to investigate but will likely be more expensive than just replacing some of the existing drain lines.

For you the expression "think before you cut" should have new meaning.

Edit -- I did a bit of looking and did find that there are reamers available that will work for 3" size plastic pipe. Here are some pictures of what they look like:

With one of these and a suitably sized right angle drive electric drill you may be able to fix your problem by reaming the nearest accessible coupling. Use does require that you be able to securely clamp the fitting being drilled into place. Also make sure that you would have a really good hold on the drill while reaming.

Rather than trying to point you to a specific web site I would suggest that you do the Google search for "PVC Pipe Reamer".


Toilet intermittently continually fills My toilet has started running on after flushing - water continues to enter the cistern from the top of the fill tower, and flow out through the overflow. It's not a "perfect" failure; if I depress the ball-float and let it bounce back up, sometimes that shuts off the valve and the water stops - but it doesn't shut off every time. I don't seem to be able to stop the water by manually lifting the float (to exert more pressure on the valve).

I'm guessing I need to replace the valve that the float controls, but I can't find a definitive answer or instructions - largely because I'm not 100% clear what that specific valve is called (so this might be a duplicate for the same reason - sorry!)

I've attached a picture of the cistern, with the valve I think is faulty marked, in case this helps diagnosis.

It's difficult to tell without a close up photo of the valve however your guess sounds correct.  It's possible there's some grit or chalk built up that's preventing the valve from closing fully.  Unscrewing the part you've circled may allow you to verify and clean it out.  Ensure you turn the water supply to the cistern off before removing the part.


What can I do about this gap between my driveway and the street? I have a low car and the ditch between my driveway and the street is pretty big. I usually enter my car in reverse at a very steep angle as to not have it scrape the lower front. My neighbors park cars pretty much around the driveway and it is sometimes not easy to get in at such an angle as not to scrape. I would like some suggestions I can do on the curb itself to alleviate this problem.

The drive way is about 14 feet long. The ditch is about 18 inches (between the driveway and street) and 3 inches deep.

The street is slightly higher than the driveway. If I get a chance, I’ll take a picture with a level.

More pics

More neighbor examples

The gap exists for drainage.  Technically, it's a gutter.
In order to create a level surface to drive on, you need to fill at least part of the gutter - but you need to do so without impacting the gutter's drainage ability.
Any permanent change you make WILL need to be permitted by the city/county, or they will likely make you take it back out again at your expense.
A not so permanent solution, however, would be to assemble a ramp structure which can be removed and which can support the weight of your car without impeding water flow.  Something with a very rough design like this:

For the strength to surface area needed you're probably going to need to use metal.  Unless you're a welder/metal worker this may not be a DIY project at all.


Should I use remodel or new construction recessed fixtures when installing a new ceiling? We have a stomped ceiling on the first floor in our new home (built in 1969) that we want to get rid of.  Every contractor we've talked to says that scraping it off isn't an option because it's been painted over, so we are opting to install another layer of drywall over the existing textured ceiling.  We could also rip down the ceiling, but that seems like more work than we want to do right now, but if that's the ideal scenario, please comment on that.

Since I have the opportunity, I want to install recessed lighting because I can cut into the current ceiling and run electrical and cut as many holes as I need to in the drywall since the ceiling will be covered over.

My question is: Would it be better / easier to use remodel or new construction fixtures?

Here are the scenarios I am currently envisioning as options.

Install remodel cans into the existing ceiling and then drywall over this with the new ceiling and cut holes for the cans in the new 1/2 inch drywall.  This would mean that the lip of the remodel can is stuck between the new and old drywall and the trim that I attach to the can would have 1/2 of drywall between it and the actual can.  This is what I'm leaning toward, for ease of installation, but is it a problem to have the trim 1/2 in away from the can, with the trim against the drywall?
Cut bigger holes in the old drywall and use new construction cans.  This seems like it'd be more work, but I could lower the edge of the can down to the edge bottom edge of the new drywall, so the trim is right up against the can.
Install remodel cans into the old drywall and wire them up, then take them down when the new drywall goes up and then cut new holes in the same places and re-install them so the lip is flush to the new drywall (but I would have to modify the clips so they can accommodate 1" thick drywall).
Bring down the old ceiling completely and use new construction cans.  (seems like a lot of work)

The only other concern I have is that 1-2 rooms are additions to the house where there is no attic access, but I believe (hope!) there is insulation above them.  Do either the remodel or new construction install lend themselves to making sure that I get adequate insulation above the cans if I can only access them from below?  I am using IC rated cans even when there's no insulation.

Thanks for your input and advice!

EDIT: I did remove the ceilings and it was a good thing too, found several issues including HVAC vents cut off without being replaced so that a few rooms didn't have heat or cooling!

Scenario #4

I would just remove all the old drywall and use new construction fixtures. It may seem like a lot of work but all these other problems go away. Plus my "drywall guy" would throw a hissy fit trying to finish a layer over another layer with a texture. The drywall won't lay flat like it should and finishing will cost you more money or it won't look right.

Pulling down old drywall goes a lot faster than you think, especially if it is nailed instead of screwed. Once you get started large pieces can be pulled down.

One problem is the ceiling drywall is usually installed first so the wallboard is supporting it (trapping it) at the edge of the room. While pulling it down the wallboard could be damaged if it is not cut loose. Replacing it will require inserting the new ceiling drywall above the wallboard.

Good luck!


How tight a fit for a chimney liner? We are evaluating what size flexible chimney liner to use for a new fireplace (masonry heater). The liner will pass through an existing concrete flue.

The flue is constructed out of 16" square concrete blocks which have an interior of 8 1/4" - 8 1/2". The measurement varies a little depending where we measure.

The flue is not perfectly straight but was constructed with some gradual bends in a few places, I assume to avoid house framing and the roof ridge.

So the question is whether an 8" stainless flexible liner would be able to fit into a flue like this, or would it be too close a fit? The chimney is about 30' long (2 story house).

The next size down seems to be 6" which seems like it would be acceptable but might not draft quite as well, although its substantially cheaper.

Thanks

I think you'd have one heck of a time trying to get an 8" into that hole.

Unless incredible care was taken with the inside joints, there's very likely some point where a bit of mortar is poking out that will block the liner, or an offset between blocks at a "slight bend" will,  given only 1/4 inch of clearance.


How can I tell if this is a split bus panel with no main breaker? Looking for the main shut off or to confirm this is a split bus. Thanks!

The arrangement of the breakers looks like my 50-year-old GE split bus panel. With the dead front off I can see the wires that go from the lower right hand one of the four 2-pole breakers at the top to the lower bus. In my panel the lower right 2-pole breaker is a 60-A breaker which feeds the lower bus for all the 1-pole breakers below.

In your panel it looks to me like the lower left 2-pole breaker has two heavy wires which "disappear" under the 1-pole breakers and so may connect to the lower bus. If you switch off this breaker, does this cut power to all the 120-V circuits?

What are the four 2-pole breakers powering? In mine they are (CW from lower left) electric dryer 30 A, a/c condensing unit 40 A, electric range 50 A and "main" 60-A feeding the 1-pole breakers below.


Use 60Amp disconnect as a pass-through to another disconnect We would like to add a second air-conditioning unit.  The original 60 Amp disconnect is grounded via EMT to the panel.  The existing EMT will meet code requirements for both conduit fill and derating requirements (this was asked in a separate question).  I would like to use the existing EMT to run additional wiring through the existing disconnect to a new disconnect for the new unit.  Is this code compliant?  Thank you.
Elmo

This should be fine, but triple-check the fill if you want to be sure, and make sure it's labeled properly too!

Your usecase (extra wires run through a disconnect box to another disconnect) falls under NEC 312.8:

  312.8 Switch and Overcurrent Device Enclosures with
  Splices, Taps, and Feed-Through Conductors. The wiring space of enclosures for switches or overcurrent devices
  shall be permitted for conductors feeding through, spliced, or tapping off to other enclosures, switches, or overcurrent
  devices where all of the following conditions are met:

  (1) The total of all conductors installed at any cross section
  of the wiring space does not exceed 40 percent of the
  cross-sectional area of that space.

  (2) The total area of all conductors, splices, and taps installed at any cross section of the wiring space does not
  exceed 75 percent of the cross-sectional area of that
  space.

  (3) A warning label complying with 110.21(B) is applied
  to the enclosure that identifies the closest disconnecting
  means for any feed-through conductors.

The 40% and 75% fill rules are trivial in this case -- the gutters on even the smallest disconnects are larger than 3/4" EMT in order to provide the Code-required wire-bending space, so you'll be nowhere close to either one.  Since these are true feed-through conductors, though, the existing disconnect will need a a label applied to it in accordance with 110.21(B), though:

  (B) Field-Applied Hazard Markings. Where caution,
  warning, or danger signs or labels are required by this
  Code, the labels shall meet the following requirements:

  1) The marking shall adequately warn of the hazard using
  effective words and/or colors and/or symbols.

  Informational Note:
  ANSI Z535.4-2011, Product Safety
  Signs and Labels, provides guidelines for suitable font
  sizes, words, colors, symbols, and location requirements for
  labels.

  (2) The label shall be permanently affixed to the equipment
  or wiring method and shall not be hand written.

  Exception to (2): Portions of labels or markings that are
  variable, or that could be subject to changes, shall be permitted to be hand written and shall be legible.

  (3) The label shall be of sufficient durability to withstand
  the environment involved.

  Informational Note: ANSI Z535.4-2011, Product Safety
  Signs and Labels, provides guidelines for the design and
  durability of safety signs and labels for application to electrical equipment.

Given all that, I would simply make up a printed label that says "Caution: Feed-through conductors are disconnected by breaker XYZ in the panel" where XYZ is the label given to the new breaker in the loadcenter's directory, and apply it to the inside of the existing disconnect's cover where it's sheltered from UV, water, etal.


Roll up garage door spring ... unwound? A couple of days ago we lost power and I had to open the garage door manually. The door did not stay up as it is supposed to. It stay half the way so I had to shove a piece of wood to keep it up and move my car. We hardly ever loose power here (California, USA) so I never bother to look at the springs. Now I was looking at it to plan adding torsion to the springs so the door would stay up and I noticed that the left spring looks unwound (comparing green arrows). It also does not feel hard like the right one. You can see it a bit wavy?  I installed the springs myself about 4 years ago. I can easily rewind it but I'm concerned what would happen when I loosen up the bolts (two bolts on each spring pointed to by red arrows). I tried to move the left spring by inserting the handle bar but it is not loose. It wasn't hard doing the install but adding torsion is not without risk.
Any chance the springs are slipping from the cups (ends)?
Thanks

The paint marks are used as a general guide to how tightly the spring is wound.  In this case it's clear that the right spring is wound more tightly than the left one.  Yes, it's possible that the left one has slipped or they were not evenly wound to start with.
The two springs should be tensioned the same and this is done by counting the turns as you wind them.  The tension should be set so that the door is roughly "neutral".  By that I mean that it can be moved up and down with minimal force from either the opener or from a manual operator if the opener is disconnected.  At the top it should stay up when properly tensioned.
You are correct, however, that tensioning these springs can be very dangerous!!  But using proper tools and methods and wearing safety glasses you can minimize the danger of personal injury.
Using the winding tool that fits snugly into the sockets on the hub, you take the tension off the setting bolt and then loosen it.  Now using one of the tools (you will need two of them) you can wind or unwind it from about 1/4 to 1/2 a turn.  Repeat until you have tightened to the desired tension or loosened it fully.  DO NOT RELEASE THE HUB AND LET IT SPIN!!  That is VERY dangerous!
If you find you are unable to do this yourself safely, please call a qualified overhead door service tech.


Unsupported Subfloor Hanging Over Joist I'm renovating a 2nd floor bathroom and I made the mistake of cutting out the subfloor flush with the wall shared by the doorway. The problem is that this wall sits between 2 joists so my new and existing subfloor butts up against one another in unsupported space.

My original solution was to install blocking but the issue is that there is round duct work that runs directly under the wall between the joists. I've considered adding another joist but there is only 5 inches of space between the joist and the duct work. What is the best solution given this situation?

Ended up creating a bridge under the subfloor gap using a 2x8 that sits on a 2x4 sistered to the nearest joist. I used construction adhesive and screws to attach both subfloors to the bridge. There is no longer any bounce in the floor.


Can I use a socket conversion unit to split a washing machine socket in order to add a dishwasher? Is it ok to use a socket conversion unit to split a washing machine socket into 2, so that we can use it for a dishwasher?

The socket conversion unit is 13Amp and the switch above the kitchen worktop does look like the cooker one (i.e. doesn't have a big red switch).

As you might be able to tell, I'm pretty new to this.

EDIT:

This is the socket converter I've got:

I've also found the instructions for the washing machine, which does say not to connect it to an extension lead nor multi-socket. However I'm unsure whether a conversion kit is considered as a multi-socket.

The answer to that question in Electrical standards is NO!

The problem is that both these machines use heating elements that can cause surge power to heat water. Now if you use(not you but anybody unknowingly) use them at the same time it could cause an overload. Fine- you are protected by 1-The wall plug, 2-The DB Breaker.

Causing such an overload during peak operation of machines can cause unwanted deterioration of equipment and unnecessary load on electrical wires.

There do exist double isolators(the one on the wall with the red switch/light/fuse)(but they are rare) that can be rated separately by Amperage and should not exceed the amperage of A) The circuit breaker in the DB (taking into account that the proper mm2 wire is used) B) The wattage rating of the actual device

I am completely talking theory here based on what I think it should be(but does not mean that is your case)It could be likely that using the single isolator you could use two sockets-but they have to be certified in order to count towards a propel installed wiring system- and only a certified electrician(qualified does not mean certified) can help you out.

BUT

So the forumula is simple Ohm's Law

Washing machine = 1000Watt
How much is a 1000watts? 1000(Watt) / 240(Volt) = 4.2AMP MAX

If I were a gambling man i would bet a 100 bucks your wall isolator is up to 15AMP and your DB breaker is 5AMP using a 1.5mm2 cable. So how could you possibly accommodate another device of a similar wattage.

Another way.
How much is 5AMPs? = 5(Amps) * 240(Volt) = 1200Watt

When we used to install electric water boilers we were required to use 5mm2 solid copper (3500Watt) and 15AMP Breakers and nothing else is allowed to leach of that circuit.The Units had dedicated isolators in the loft near the unit and internal safety breakers.

To elaborate on your question and demonstrate the difference.

What you are replacing is a switch system that "Isolates" electricity in the event of electricity leakage or short circuit. Isolates means it creates a gap in the Neutral and Live at the same time Isolating the device from all electrical currents(Earth should also be isolated but that is another story-and usually is not)

What you want to install is a normal switch.When you turn it on-it turns on weather there is a short or leakage and will not turn off in the case of fault- causes backwards stress to the DB to trip the circuit. This does not Isolate the circuit. It just cuts out the Live, meaning that if for some unknown reason there was electricity pumping back into the neutral.. it could cause a fire or other damage.

The AMP rating is just what it could handle at MAX peak current.

SO..

The simple answers by many would be- Yea use a splitter- it will be OK (and most likely if you call Dave your neighbourhood white man van- he will install for you for a few bob and nothing will ever happen.. but if he guarantees it he is lying.. so don't be fooled.)

But a professional answer will be NO- It wont be OK- especially if your home insurance finds out after it ....

It may sound stupid, and could  cost a bit- but be safe- Rent a certified electrician and demand a certificate of testing once complete and Tell your insurance.

There can be no maybes in human life - these things cannot be taken lightly- You feeling lucky? Go play euro millions.


New Hardwood Floors Chipping I just bought a newly built house in Maryland and have been living in it for about three months. Most of the house has hardwood flooring that for the most part looks really good. However, I've found some spots here and there throughout the house that are starting the chip.

What are my least invasive options for fixing this problem? I say least invasive because I do not want to tear up the whole peg board and replace it. I'm thinking that I could put down some wood glue and try to stain that small piece or something; If that's the solution can anyone recommend the materials I need to do that or brands of glue, etc. Or is that a bad idea? I don't want my repair job to be noticeable.

I'd agree with Ed Beal, start a warranty claim in case you start finding it all over. Otherwise yes, if you can lift the feather/chip & work some glue in there that would be great. Immediately wipe up any glue that squeezes out when pressure is applied.

Make sure you put a piece of Saran wrap over it to then clamp it down with something heavy. The Saran wrap ensures you won't glue your heavy item to the floor.

Assuming that works & it seems nice & solid, then you'll need to put at least 3 coats of clear polyurethane over it to avoid Foot, Mop or Swiffer injuries in the future.


Should drywall used on a ceiling be of a different weight/grade than drywall used on walls? Should drywall used in a ceiling be of a different weight/grade than drywall used in walls?

We are demoing a closet this weekend, and will need to repair the remaining drywall in a few places.

Depends on the ceiling/wall function. In most cases for repairs you want to replicate what was there, unless you are ripping the entire wall/ceiling or it's too hard to track down matching replacement drywall.

If the wall/ceiling is a firewall, you normally need to replace the structure that was there, which may be double-layer 5/8 type X ("firecode") gypsum. I prefer it for ceiling applications anyway (single layer where double-layer is not needed), as it's far less prone to sag than the thinner grades. It's also heavier, which you may not be fond of - and it is sometimes used on "acoustic" walls for that reason.

I've dealt with old walls that use as little as 1/4" drywall. 1/2" is what's normal/standard in new construction - 1/4 and 3/8 may be available from a supplier but I would only use those for repairs of a wall starting with that thickness where replacing the whole wall doesn't make more sense.


Is a tank-style water heater always under pressure? Is a tank-style hot water heater always under pressure?

In other words, is the entire tank pressurized?

Is the pressure largely created by the force of the incoming cold water supply?

Yes, the tank is under pressure from the incoming cold water supply. After all, the incoming cold water is what is pushing hot water out of the tank and into your faucet.

However, there are usually two safety valves:

Temperature/pressure relief valve that will let the hot water or steam out, if internal pressure or temperature goes over a certain limit.
A vacuum breaker valve that will let air in if internal pressure is less than external (air) pressure: prevents the tank from collapsing if there is no cold water coming in and you're pumping hot water out.


pressure tank overcharging I replaced my 1/2 hp well pump a month ago, after over a decade of use. All seemed well until short cycling began. I hope I am using that term correctly. Essentially what is happening is the pressure switch cuts on almost immediately after a tap is opened and cycles on and off at a very rapid rate during the time the tap is open. When this first happened, i drained the pressure tank completely and checked the air pressure. Very high. Bled the air down to 38 (for a 40/60) and things seemed normal for a week or two. Then it did it again. Checked the pressure and same result. I've just bled off the pressure a second time....what is happening?

Your bladder has a slight leak, and water is leaking in to the airside, raising the air pressure. It will eventually fill with water, and you will see water coming out of the bladder when you attempt to bleed it down.


How do I install a dimmer switch? A friend was trying to help me install new dimmer switches and instead of disconnecting one wire and putting it on the new switch, he just cut the wires and couldn't figure out how to put them back.

I used my multimeter to find which wire was which and got the three way switch to work, however next to my three way switch I also have a single pole switch for the lights above my sink. Now, that switch alternates with the three way switch. One set of lights goes on, and the other goes off. If the switch by the garage is off the lights above the sink won't work. I think I have the traveler wires reverse??

Typically A dimmer that can be used in a three way circuit will have a common (black) wire, and two (non-black, non-white, non-green) travelers.  Here is a wiring diagram from the installation instructions of a random dimmer.

It can also be installed as the second switch in the circuit.

As you can see, in this example the common wire is black, while the travelers are red. Without further detail about your current wiring, it's impossible to provide more assistance.


Foundation Built on Ledge Rock A corner of my houses foundation sits on ledge rock. There's some corrosion that lets moisture in where the foundation meets the rock. The foundation is field stone and was built 100 years ago.

Why would someone build on ledge? And how can I repair the foundation? What materials do I use? Cement? I'm a new home owner and have lots of questions, sorry.

Thank you in advance.

Someone built on rock because the rock was where they wanted to put the house. This mighf reduce foundation cost, too.

You repair the foundation the same way you repair any brick or fieldstone foundation -- mortar in new pieces if necessary, tuckpoint to fill in eroded-away mortar, etc. Think of the ledge rock as a natural foundation slab and work from there.


Puzzled why motion sensor set off home alarm while away! While I was out of town, my neighbor had called and left me a message that my home alarm was running for about 15 minutes on Christmas Eve.  Upon arriving home the next day, I found the house secure but my security pad indicated that the motion sensor in the family room had been activated.  Outside of a roaming mouse in the house, I'm assuming that I have a motion sensor that needs to be replaced.  I'm curious if anyone else has experienced their motion detector to be erroneously set off? Is there a way to check the sensor?

Many things can set off a motion sensor erroneously, though it depends on what sort of motion sensor you're talking about.  There are a number of different types of motion sensors; PIR (passive infrared) is the most common in home security systems.
PIR works by looking for changes in the ambient temperature in areas it's monitoring, the assumption being that if there's a large enough temperature "blob" that's moving across the field being monitored, it's a person.

Assuming you don't have pets, things like a cold draft, or incandescent lights turning on/off, or an insect flying in front of the sensor could all trip the sensor.

Another possibility is an electrical fault of some sort, such that the sensor itself didn't trip, but the alarm system thought the sensor did.  If it's a wireless sensor, you may want to replace the batteries; if it's wired, you should check continuity, and that there's a resistor in place.

I can say that yes, I had a number of false positives from the motion detectors I had; I replaced them with more modern sensors, and haven't had a problem since.  If you really want to cut down on false alarms, you could get a dual technology motion sensor, so that two different ways of detecting movement have to agree before an alarm is generated.


Concrete bags vs truck for slab I'm looking to pour a 10'x14' 6" slab for a garden shed (roughly 2.5 yards of concrete). One bid would bring a concrete truck, one write get a bunch of quickrete bags (~120) and rent a mixer. The largest rental mixer would take about 8 batches to do this job. The plan is to use 6" remesh in the slab.

Would doing that many batches/partial pours cause any problems with the slab structure? What's the best way to do the partial pours - do an eighth of the area per batch, full thickness? Spread each batch thinly over as much as it will cover? Our just plop it in wherever?

You should get a batch mix for this so that you can continuous pour it from end to end in a short period of time. This is the best way to assure a uniformity and even drying time for the whole slab. Mixing in small batches often ends up with one end ready for finishing when you are still messing around with mixing at the other end.

When you get it all poured from a batch truck you then get to concentrate fully on on the troweling and finishing aspects and coverage if needed due to too hot or too cold of weather.

Another thing that demands close attention is to ensure that the wire mesh gets pulled up into the center thickness of the slab as it is poured. Too often it gets pushed down to the underlying fill sand/gravel where is does no good. I have seen this be an even greater problem with a small mixer process because many wheelbarrow trips across the area keep pushing down the mesh and it gets neglected in the due course of going back for another load at the mixer.

Lastly why not put at least some re-bar in the slab. It is a small cost adder to provide much greater strength to the slab to keep it in one piece.


How do I get a low voltage thermostat to control a 240v heater? Can someone help me understand how this contactor works?

A1 (Yellow) Always has 120v and is connected to a high limit switch.
A2 (black) Always has 120V and is connected to a line voltage built-in thermostat.

Both sides of the thermostat also read 120v at all times and doesnt change with the contactor closes and the space heater is running.

The root problem I'm trying to solve is how do i get a low voltage thermostat to control this 31a 240v heater?

Not with that contactor

The contactor in your illustration is internal to the heater.  It is a 240V contactor and should never be connected to a 24V thermostat.

You are seeing 120V because your electronics training is in automotive or hobbyist DC electronics and you are stuck in the notion of a GND/common from which all voltages are measured.  You have permanently clipped your black voltmeter lead to the machine's chassis.  If you want that to work with mains power, try moving to the UK.  Here, everything is relative, there is no common, and you must measure between opposing terminals and leave safety ground out of it.

That contactor coil is 240V.

Switch the T-STAT line instead.

The T-STAT circuit is a pilot signal for the contactor whoch carries 240V but at very little current (limited by the contactor coil).  We can use that.  Note that it goes through a couple of safety interlocks, those should not be defeated.

I would put a much smaller contactor (i.e. Relay) to replace (or in series or parallel with) the "T-STAT" switch shown on the diagram.  That would be a relay with a 24V coil, 240V contacts and insulated for 240V.

Get a 24V supply transformer (they are $12 and attach to any junction box).  The transformer supplies R and C.   Run R, C and W to the thermostat, run C and W to the coil of the aforementioned relay, and you should be all good.

If you put this relay in series with the factory Thermostat, the heater will fire only when both thermostats call for heat, so set the factory 'stat to 90F setting so it is always calling for heat.

If you put this relay in parallel with the factory thermostat, the heater will fire when either thermostat asks, this can be a great way to make the thermostats be backups for each other.  Set the latter to 40F (or whatever you consider your don't-freeze-pipes minimums) so it is rarely calling for heat.


Searching for a specific window lock I recently moved into a new place and almost all the window locks are broken and these windows are single hung and are located on the ground level. I have looked numerous places but I cannot find a similar lock and I cannot locate window manufacturer information. Can anyone tell from my picture what kind of lock this is or where I could find it?

This type of locking mechanism is a sash latch. From the picture it looks like it's not installed in the way sash latches are typically installed.

Usually this type of latch is attached to one of the sashes of the window. Here is such a latch on one of my sash windows:

You can see it's not installed into the frame like yours, instead it's on the end of one of the sashes and latches into a bit installed on the other sash. In some windows, like my basement windows (not pictured) both sashes slide, in this window I took pictures of, only one side slides. Here's a better look at the lock's position within the entire window:

As you already know, your particular latch is older and while you will probably have difficulty finding this exact model from a retailer you will likely find modern equivalents that may fit. As @keshlam, and @Comintern noted in the comments technically this latch is not appropriate for your window. Buying a new latch and installing it into the frame in the same way as your old latches could result in them breaking the same way. If you go with this approach I would recommend that you search online or bring the latch with you to a store to find a new latch that matches in dimensions and see if you can find something made out of a durable material.

Another approach that @Ecnerwal mentioned: there's no rule that says you need to use the same style of latch. If you're not keen on replacing the entire window(s), you can buy latches that are appropriate for your style of window. From your picture it's not clear if your windows are sash windows (they slide open) or casement windows (they open outwards on a hinge). My guess is they are casement windows in which case there are many options available to you. Again, you can search online or bring your window measurements to a store to find latches that will fit and suit your style.


Grounded Conductor Sizing OCPD: 400A
System: 480/277V
Ungrounded conductor size: 500kcm

How do I find the minimum size Cu THHN grounded conductor?

I tried using T250. 102(c)(1) from 2017 NEC 70 and I got 1/0 AWG but I am not convinced that I answered the entire question or even if I am on the right track.

I need to know how to approach this problem.

I am assuming we are talking about copper conductors here and the service is not a parallel feed.

NEC table 250.102(C)(1) is for sizing a service with no overcurrent protection so it is sized by the incoming conductors so it would require a 1/0 copper grounding conductor.

NEC table 250.122 sizes the grounding conductor by its overcurrent protection. So if this is after a 400A breaker, your grounding conductor would be a #2 copper conductor.

I need to make this clear. You are calling for a minimum grounded conductor which is a neutral and I am assuming you mean a grounding conductor . I am giving you information on sizing a grounding conductor. If you really do mean a neutral you shouldn't downsize it from a 500 Kcmil without professional assistance since it would require a load study.

Hope this helps.


What kind of contractor would I need to service or replace pull down attic stairs? I have attic loft with pull down stairs access to it and I need it either serviced or replaced with a new rope system. Can you advice what kind of contractor I'd need for this?

As you can see on the picture below it is not your basic attic ladder but quote sophisticated garage like pull down stairs.

The trouble with it, it's too loud pulling down and especially pushing back up. I'm thinking to move my office up to the loft but it'd be not possible to move those stairs at 1am when everyone is sleeping...

It looks to be exactly like a garage door. I take it lowering the stairs tensions a spring attached to the drums so it is easier to raise. Exact same system as sectional garage doors. The springs can be very dangerous to someone unaware of their potential. I think you should look for someone experienced with sectional garage doors, they will understand this system immediately.

If the rollers are hard plastic or rubber, the system could be made quieter by going to softer rubber. Applying foam to the closure panel could reduce any drumming effect, but will take careful detailing to keep it out of the way and looking attractive. Rubber padding could be added to stops to limit banging. A certain amount of noise is the nature of the beast, unfortunately.


Refrigerator filter dripping Replaced water filter   its dripping      we are leaving and turning off water   will that stop it from dripping while away for an extended period/

Turning the water off will limit the supply of water but it may drip unless you try and fill a glass of water (yes with the water off) this will remove the pressure from the system and should stop the dripping.


How to insulate brick/plaster walls from extreme heat? I live in Rajkot, India. Temperature goes above 40 *C (104 *F) for at least 4 months a year.

I live in a single floor house with 3 sides of house and roof is exposed to sunlight.

It's a house built with brick walls, plaster and concrete slabs. flat roof floor is tiled with white ceramic tiles. Outer walls are painted white.

Is there anything I can do to reduce the inside temperature?

Add a corrugated roof slanting from 1ft to 2ft high with the corrugations pointing to the higher side. Convection will pull the air to the higher side and out, providing some airflow.
Insulate the ceilings of your living areas with rigid foam panels to limit heat gain from the roof. Provide awnings above your windows for shading in the summer, especially on the South facing windows, use a passive solar calculator online to size the awnings properly for passive sun heat in winter.


How do I remove the old plastic dishwasher water supply line connection near the shut off valve? The water supply tube from our old dishwasher is hard plastic.  It's not flexible enough to meet the connector on the dishwasher.  The fitting  near the water supply shut off under the sink was smooth around the outside and we couldn't get it to budge with pliers.

We are trying to replace this hard tubing with a universal dishwasher connector but can't remove the old plastic. Afraid we will break something if we force it.  Once we get the plastic off, how do we get the brass PEX fitting to match the universal?

There are many ways to skin this cat. But probably the easiest one would be to cut the plastic pipe so that there is no water in it. The reason you want to remove the water is so that you can then use a hair dryer to get the plastic warm and soft. Use two pliers- one to brace the copper valve and the other to twist the plastic pipe or connector off.

If that's not working, a pipe sander or dremel tool (with a cut off wheel) could probably chew through that connector pretty quickly, but I suppose you could also try using a box cutter to cut into the connector (which looks like it will be easy if it's warm and soft). But just be careful to not cut too deeply or you might damage some copper or brass threads. You should cut most of the way through the connector and then maybe use a small flat head screw driver to pry the connector loose.


Can I add cords to recessed light fixtures to make them portable? Imagine one of those 4ft led shop lights with a 6 foot plug-in cable that you can get from anywhere. If you had a basement with finished walls and floors but an unfinished ceiling with electrical outlets up between the joists you could simply hang the light where you want and plug it in and you're good to go, right?
Ok, so now imagine you want to do the same thing but instead of that 4ft shop light you want to use recessed light housings or retrofit kits. Rather than hardwire the housing or jbox though I would wire them up with 12 ft cords with plugs. This way I can mount the housing/retrofit wherever I want and simply plug it in like any other hanging lamp, right? Or no?
The reason why is that due to the size, shape, and ducts/obstructions in my basement it's not very clear how many lights I would need nor where they should be placed for best coverage. However if I can move the boxes around and simply plug them in then I can start with a reasonable best guess and then expand the system or relocate individual lights as needed.

The NEC doesn't care what type of light fixture you cord-connect as long as you aren't burying the cord
The NEC's provisions for using cord-and-plug connections for light fixtures (luminaires) don't discriminate between luminaire types.  So, as long as you are using correct clamps in the fixture knockouts to strain-relief the cord to the box, mounting the fixtures securely so they don't strain the cord, and leaving the ceiling unfinished, you should be good to go.  Just keep in mind that if you ever do decide to finish the ceiling, you'll have to swap the cords and receptacles out for ½" KO face plates and fixture whips.


How do I repair a small rips in roofing felt from inside the loft I have a normal UK type “cold” roof, with interlocking tiles over the roofing felt.    There are a few small rips in the felt about 5cm or 10cm long; I rather not have to get all the tiles removed to repair them.   As the tiles are in a good state, I don’t have any leaks at present, but I rather fix the problem before it becomes an issue.

You can purchase self adhesive flashing which, in small pieces, should adhere well to the felt, and should be suitable for the heat and cold experienced as roofing underlayment.  The rips are small enough that this should be sufficient - if you run into a larger rip you may need to choose a different method, or support the flashing as it may fall off due to its weight if it's larger than a few square inches.

Alternately, get more roofing felt and a tube of roofing caulk, and glue felt patches over the rips with the caulk.  Make sure the caulk is rated for the temperatures, and apply it liberally so you don't create a water pocket.


How well does masonry blocks used in European home construction insulate compared to a well insulated American (wood) wall? Are there any equivalents to the Building Science insulation reports done for the US/Canada done in Europe?

I spent the last few weeks going over some properties that I will be rehabbing in France and was wondering if there was every any substantial reports done on masonry bricks.

One of the reasons that I ask is that a couple of the properties we were thinking of using more American techniques to add on square meterage but even though I have a good relationship with the inspectors they said they would want to see some substantial support that the methods I use exceed the "normal" methods.

Insulation value of masonry walls vs wood-frame walls

You should be able to find guidance. For example Scottish Guidance, UK Guidance

In the UK, I believe regulations specify maximum U-values

  U-values are measured in watts per square metre per degree Kelvin (W/m²K).
  So for example, if we consider a double glazed window with a U-value of 2.8, for every degree difference in temperature between the inside and outside of the window, 2.8 watts will be transmitted every square meter.

  A range of possible U-values are indicated below for the purposes of comparison:

Solid brick wall                2.0
Cavity wall with no insulation  1.5
Insulated wall                  0.3
Insulated roof                  0.2
Single glazing                  4.8
Double glazing                  2.8
Low e double glazing            2
Triple glazing                  1.5
Floor                           0.2

  Part L of the Building Regulations (Conservation of fuel and power) now prevents certain forms of construction by setting limiting standards (ie maximum U-values) for building elements.

More detailed advice on construction suggests various combinations of materials to meet U-value regulations.

So, if regulations in France were comparable to those in the UK you might need evidence that your constructed wall will have a U-value less than 0.28 W/m²K and that the overall building's U-values still meet regulations.

In France, I imagine your best bet is to find similar French specifications or EU specifications.

Some notes about U-values, R-Values etc

I have a small "Architects Pocket Book" ISBN 978-0-7506-8617-4 which contains all sorts of strange and wonderful information, including the following:

Thermal Conductivity (K Value)
The heat (W) transmitted through unit area (m²) of a material of unit thickness (m) for unit temperature difference (K) between inside and outside environments, expressed as W/mK

Thermal resistivity (R-value)
The reciprocal of thermal conductivity. i.e. mK/W. It measures how well a material resists the flow of heat by conduction.

Thermal resistance (R-value)
This measures how well a particular thickness of material resists the passage of heat by conduction, calculated from the R-value in units of m²K/W

Thermal transmittance (U-value)
The reciprocal of thermal resistance. i.e. W/m²K. This measures the amount of heat transmitted per unit area of a particular thickness per unit temperature difference between inside and outside environments.

U = 1 / (Rsi + Rso +Ra + R1 + R2 + R3 ... )

Where

Rsi = thermal resistance of internal surface.
Rso = thermal resistance of external surface.
Ra = thermal resistance of air spaces within construction.
R1 = thermal resistance of successive components.

Note that for wood frame construction I understand you have to average the U-values for the parts whose cross-section is all wood (where the wooden structural members are) and parts which contain voids or insulation-filled spaces. I assume this has to be an appropriately weighted average (by area of each type of cross-section).


How to cut 2-1/4" diameter hole in sheet metal box? I have a sheet metal (galvanized steel) box on my roof that's currently protecting the return and supply ducts for my old package unit air conditioner. I'm replacing it with a split system, and repurposing the steel box and original holes through the roof for the new refrigerant lines.

I bought a set of Sigrist exit seals to use for the horizontal penetrations of the new refrigerant lines through the wall of the box, but I have no idea how to actually go about CUTTING the 2-1/4" holes they require... the holes are way too big for a drill bit, and (AFAIK) hole saws are only for cutting through wood (and other relatively soft materials).

I cut holes in sheet metal with hole saw bits all the time.  Depending on how thick your material is you might need more than one hole saw to get through it in a reasonable amount of time.  22 gauge is certainly no problem.  Not sure how thick your sheet metal box is.  You want the ones with the most teeth but generally these are the cheaper ones so you should be fine.  I am not sure I'd try on 1/4" plate steel but sheet metal shouldn't be a problem.


How do I fix my "OLD" glass door knobs? In my 100+ year old house, every interior door is made of solid wood. Their locksets have glass knobs connected by a square threaded rod which actuates the latch.

I have found replacement parts at hardware stores, however they have lasted only a couple of months.

Is there a way to install a modern knob in one of these doors?

Three options:

Buy vintage glass knobs and shafts.  These are widely traded on eBay as of this writing at about $40/pair.  If it survived 50 years in a different house, chances are it was well made.
Buy better quality reproduction glass knobs.  The item you pictured is looks like plated brass.  Get the solid brass stuff for more money.
"House of Antique Hardware" (http://www.houseofantiquehardware.com/) can get you set up just fine.  The cheap stuff is about $35, the good stuff more like $45 a pair.
Get reproduction or vintage cast iron or steel knobs.  These won't break, even with a hammer.

If you get glass knobs DO NOT OVER-TIGHTEN THE SHAFT.  It will contact the back of the glass knob and break it.  Mark the depth of the shaft before threading! Tighten your set screws properly.  Tighten set screws so they hit the flat, not the angles, of each shaft.  If the turning pressure is too high take the lock apart and find the problem (lubrication is optional, but chances are a spring is jammed in the works or something is bent).  These locks are simple to take apart.

The extra effort to use vintage is worth it: the house likely won't look right with modern knobs.  See also Fixing vintage glass doorknobs with loose glass to brass connection


How can I transition a square duct to round of the same outer size? In remodeling my bathroom I had to convert a 6"x6" square duct underneath the floor joists in the basement to flex so I can get around my new toiler drain. I cannot for the life of me find a 6"x6" square to 6" round transition anywhere.

Do I need to fabricate one myself? I don't know what to do.

I am aware that a 6" round duct is smaller than 6"x6" square by ~20%. It feeds the foyer which I have kept the damper nearly closed anyways because it gets very hot/cold in that location.

They do exist. Best bet is probably to contact a local sheet metal shop, if they don't have one they can build one. Expect this to cost in the tens of dollars range.

You could potentially cap the end, and then use a round duct takeoff. The downside is it will restrict flow to the vent because of the abrupt end and sharp angles internally.

There's another type of side takeoff that is rectangular, and if you can find one you could potentially modify it yourself using a couple strategic cuts and copious amounts of foil tape.


Shutting off water during extra-long term vacancy If vacating a condo (for context, high floor apartment-style unit in hi-rise) that will not be used for quite a while, is it ok to shut off it's water for as long as TWO YEARS?

There's nothing wrong with shutting off the water for that length of time provided you take the proper precautions. The water in all your traps for the sinks, toilets and showers will evaporate and allow sewer gas and bugs to get into your condo. They should be adequately sealed to prevent this. If you have a water heater, you should drain it and shut off the breaker if it's electric. Drain the water from your fridge, and very importantly use tape or something else to ensure the door is slightly ajar the entire time (otherwise you get terrible stink).
Have your maintenance department shut off the water from outside your unit so a leaky valve won't be your problem.
Or, hire a management company and let it be listed on AirBnB.


Small alcoves in exterior walls for utilities access? I am in Oaxaca, Mexico at the moment and almost every building seems to have these – photos from Google Street View. Am I correct that they are to give the fire department access to gas and electricity lines without going into the building? How would one correctly refer to them in English?

They appear to be giving access to meter readers, and nothing more. The one with pipes could be water or gas. Alcove works, as does recess (a multipurpose word, but one meaning is the sort of hole in the wall pictured with meters in it.) Niche could also work.


Alternative to using a bearing on threaded rod? I have a project where I use a threaded rod to allow a piece to move up and down the rod when rotated (much like a deodorant stick) now I need to fix the threaded rod to it's container in such a way that still allows the rod to rotate but not allow it to move any other way. My idea is to use a bearing between the rod and the container. The only way I can think to do so would be to weld the bearing to the rod. Is a simpler way or an already made piece of hardware to do this sort of thing?

Put a thrust bearing in the container and then, on the rod you can put a washer followed by two nuts.  Tighten the nuts against each other so they don't move.  Or maybe a nylock nut.

Assuming I'm understanding your question right.


Wiring a switch to an outlet to control Garbage disposal I have a gfs outlet with the power coming to it.Can i install a swith next to it to go to a outlet under my sink to power the garbage disposal

NO. You CANNOT power a disposal from an existing kitchen counter receptacle circuit.

If the dishwasher is on a 20A circuit typically you can share that circuit, other than that usually they are on a dedicated circuit.


Insulating a post and beam construction roof/cathedral ceiling My house (built 1972) has a cathedral ceiling with post-and-beam construction in the main room. The ceiling temperature can get as high as 90F, or even greater on a very hot sunny summer day, as measured from the floor with an IR thermometer ("gun"). The roof doesn't look to be very thick, probably less a foot in total? I'm not sure what insulation is in the roof, if any. This room has quite a few floor registers, however, it is still much colder in the winter and hotter in the summer than adjacent bedrooms (~5F). I was wondering if there is anything that can be done to improve the efficiency of heating/cooling this room. Can more insulation be blown in between the pine ceiling and the roof?

I live in sunny eastern Washington, hot dry summers 100F+, sometimes cold but not too bad winters, 10-20F lows.

I don't need a new roof yet, the current asphalt shingles look fine so I don't want to do something as drastic as replace the roof to add more insulation but it would be good to know that is an option for the future.

The tongue-and-groove wood planks conceal insulation above them, probably fiberglass batts between the rafters. As you've observed, they are clearly insufficient, because the room is too hot. There are two safe ways to improve the situation:

Add more insulation underneath the existing ceiling wood, then install a vapor retarder (retarder, not barrier. A smart membrane, not poly sheeting), then cover that up with drywall.
Remove the roofing materials and install 4-8 inches of rigid foam insulation board above the roof decking, then new roof sheathing over that, then new roofing materials.
Build a metal roof (white or bare metal) over the existing shingle roof, using eave-to-ridge 2x4s to build ventilation channels under the new roofing. Such a roof will reject the vast majority of the sun's rays, which is the primary driver of heat gain.

Since you don't want to mess with the roofing, that leaves option 1. If you don't want to ruin the look of the ceiling with the tongue-and-groove boards, you're out of options and will have to live with the situation.


Do dishwashers and clothes washers require dedicated circuits in an older home? 2 part question Thanks in advance.

My home was built in 1969.  My dishwasher is currently on a 20 amp circuit.  It is also shared with the garbage disposal and 1 gfci electrical outlet. We rarely use that outlet for anything.  Is this a code violation or hazard?  I do run the disposal on occasion when the dishwasher is running.  If this is a hazard,  I would like to have an electrician update it.
My washing machine in the basement was on on it's individual circuit but a radon fan was installed and tied into that. Should I get another separate circuit for that also?  Thank you.

I do not believe either of these situations is hazardous.

However, keep in mind that codes have changed over the years to require a lot MORE circuits in the kitchen than (typically) there used to be. In particular, you should have at least one circuit for small appliances, separate from the disposal, dishwasher and other built-in appliances. But if everything is installed correctly then it is perfectly safe as is, with the catch that if you run a toaster AND disposal AND the dishwasher is doing a heated dry cycle (the motor & controls the rest of the time use relatively little current) then you may trip the breaker.

A radon fan should not use much electricity - I wouldn't be concerned about combining it with your washer circuit.


upgrade to a 200 amp service, cable wiring sizes The house currently has a 3/4 inch conduit to feed the main wires coming from the power company to the breaker box. This is very much inadequate. I plan to upgrade to a much bigger breaker box.
My question is what size wire should i use from the meter to the breaker box. There is no NEC or any kind of regulation here and SE wire doesnt exist here so ill just run separate wires through a new conduit.

For a 200A residential service in the US or Cananda typical would be 4/0-4/0-2/0AL or 2/0-2/0-1/0CU conductors. Either combination would normally be run in 2" conduit.

This is only scratching the surface of what you need to know to do this project. Are you aware and knowledgeable of all the other requirements/codes/etc???


How can I repair a hole in wood laminate kitchen countertop? Builders made a hole in the worktop, the surface is a laminated wood. What is the correct way to repair this ?

You can use "burn-in" or "fill" sticks to repair high pressure laminate as shown in this video.

http://m.youtube.com/watch?v=Li_i1Vdr7xU


How do lawnmower blade sizes work? I went to my local big box store this past weekend to find a replacement for my lawnmower blade (it's a Craftsman Precision Plus if that makes a difference, but it shouldn't).

When I got to the lawnmower blade section, I was impressed to find about 50 different sizes, although they all looked to be the same length.

However, despite very little variance in length, some were billed as being "42 in." (inches?) while others were billed as "21 in.". Although some were definitely longer than others, the variance was no more than a few inches. No way one was actually 21" and another was 42".

How do blade sizes work? Is "21 in" actually 21 inches? If so, how does that explain variances of only a few inches?

Mower blades are generally sold with the length designation matching the mower deck width. A larger riding mower may have a swathe width of 42", but they'll usually use two or more blades in a side-by-side or staggered configuration rather than one large blade.

So before buying, figure out what brand your mower is, and what the deck width is. Then when you're looking in the store, match the brand and deck width with the mower blade set. The blades won't actually be 42" long - probably more along the lines of 21.5" or 22", since they have to overlap a bit for you to not end up with a center stripe of unmowed grass.

For example, this pair of blades meant for a 42" riding mower are 21.5" long each, and this pair of blades meant for a different brand of riding mower are 25.25" long each. The reason for the different lengths but the same overall width, is that the mowing decks have different geometries of how the blades are spaced and staggered.

The blades labelled 21" were probably for a push or walk behind mower with an actual deck width of 21".


Help in identifying a mystery wall socket I am trying to identify a mystery wall receptacle that I have in my house (built in the 60s, USA).  I have one in the living room next to a fireplace, another in a bedroom.  It looks somewhat like the C8 socket, but is more rectangular and rough-looking.

Does anybody know what this is?

EDIT: added opened picture

Thanks for providing the "opened" picture, which clearly reveals that this is 300 ohm TV (and/or FM radio) antenna twinlead.

Not quite as obsolete as a buggywhip, but pretty close.


Wiring gas hob with electric ignition to mains We are currently in the process of moving into our newly renovated house. The electrician has completely rewired the house, and the plastering has been done. Only when we went to install the oven and hob did we discover that the electrician hadn't added a socket underneath the worktop for connecting the electronic ignition of our gas hob.

There is a cooker control unit (CCU) for the oven, but no single socket for the 3A plug of the hob. I don't want to drill through the work surface and lose the single socket on the CCU. My question is, can I simply hard wire a surface-mounted single socket to the cooker outlet, and then plug the hob's ignition into that?

If it is solely for the use of the electronic ignition then wire it in anywhere you please. The ignition does not use that much power.

But if it has a electrocnic cooker then you need a dedicated socket AND dedicated breaker with out anything else running on that ciruit, which is also rated at high amperage and earth leakage.(Usually stoves likes this do not use a plug but have to be hard wired with copper cable into the oven where there are several warning messages)


How can I find the circuit breaker that my outdoor outlet is on? I have one outdoor outlet where there is no power coming in and I am unable to determine which circuit breaker it is on so I can restore the power.

The first thing to check since this is an outdoor outlet is to see if there is a GFCI device built-in ("test" and "reset" buttons on the outlet). The GFCI may have cut power to the outlet. Sometimes several outlets are connected to a single GFCI so if there isn't one at that outlet look for others nearby. All outdoor outlets are required to have GFCI protection since the 1970s, although sometimes older homes haven't been updated.

If the GFCI is fine or you can't find one, next check the breaker panel. A breaker that is tripped should is identifiable because the switch is in the middle (neither ON nor OFF). However sometimes it can be difficult to tell, especially with older breakers that have a little bit of wiggle.

The easiest thing to do is to turn them all fully OFF and then ON, one by one. Alternately, some circuit breakers have the GFCI built into them, so try the "Reset" button if you see one.

Once you have identified the breaker, update the label next to it so that you don't have to guess next time.

If you can't find a breaker that restores power, check for a sub-panel somewhere and/or double-check for a GFCI (could be somewhere unusual).

(Bonus tip: if you are trying to identify the breaker for an outlet that works, plug something loud into it: a radio or a vacuum cleaner turned on. Then when you are at the panel you can hear the sound stop when you have flipped off the correct breaker.)