How can I repair the rust penetration in my air compressor? I have a compressor that I use for pumping my bike, and now a hole came out of nowhere in the tank. See picture. And some orange powder also came out of it.

Question

Does there exist glue or similar that can close the hole?

I highly recommend against attempting to repair a tank that handles compressed air at over 100 PSI. Failure could be impressive and catastrophic. None of the liquid repairs designed for fuel tanks or tires are in any way appropriate, and a full reconditioning is not cost-effective.

fred_dot_u is correct that the damage was caused by internal moisture. The entire tank is compromised, and the scope of the damage is likely far greater than what's indicated from the outside. The fact that the penetration is so high up seems to indicate neglect. A compressor should be drained daily after use.

Retire the compressor, or fit a new tank that's rated for the intended purpose.


How do I fix a stripped hole in a vinyl casement window? While replacing my window crank with a T-crank I noticed the screw that is holding the gear box in place didn't seem to be doing it's job.  Upon further inspection it seems that it's stripped out.

How do I fix a stripped hole in vinyl?  Can I just use toothpicks and wood glue like I normally would?

I mentioned a longer screw in my comment, I need to expand on this. A longer screw of the same size may need to be inches longer to contact wood framing because of shims. But a longer screw that engages with framing will not affect the gear box functions. A larger screw as some suggest may affect the gear box. I have used longer screws on high precision gear boxes that worked as well or better than the original that stripped out. But going larger may cause offset or problems with the gears in simple from the larger head and or shaft.


Why are boards replaced in a laminate floor duller than the others? We recently had to replace several planks. We used what we had left over from the initial installation.

Those boards are dull and I'm unable to get it to the same finish as the original.

Any ideas what happened? Why it happened? and how I make the replacement boards shiny?

Interesting question. It sounds like the installed flooring has become polished by wear or was at one time sealed with a gloss finish.

If you have additional replacement material you can test various finishes to match the installed ones. Laminate manufacturers recommend sealing the flooring after installation primarily to protect the joints from spills and from absorbing water from humid air but also to make the floor easier to clean.

Try the manufacturer's recommended sealer first, then matte, semi-gloss and gloss, then compare to the installed sections in various lighting scenarios.

If you determine a suitable match, mask the original planks, apply and rejoice.


Feedback on creative ways to sound proof - insulate existing finished ceiling Without going into details on the, well, lets call them 'domestic political restraints' inhibiting me from tearing down the existing ceiling or blowing in insulation, I'd be curious to get some feedback on a 'novel' approach to insulate an existing ceiling.
Granted, this approach would require a fair amount of drywall patchwork, but this is the best I can come with at the moment...
I'd start roughly in the middle of the room and cut a 1 foot wide hole in the ceiling perpendicular to the joists. Effectively just take a drywall knife and cut across the entire ceiling.
Within the hole, begin stuffing insulation batts (perhaps mineral wool) down each side of the joints until I can't press any more in. Granted this wouldn't be air-tight but would drive some r-value and create soundproofing.
I was also thinking of using an extendable stick (e.g. pointer stick or hiking stick) that I can  insert into ceiling small and then lengthen within the joist to give some extra pushing power if needed.
Is this just ridiculous?
(Per a question from a commenter, note that primary goal is sound isolation over adding r-value. Would be curious if someone would recommend just adding a 1/2 drywall w/ Green Glue sheet on top of existing rock for a reasonable STC gain)

Check out 4x8 sheets of "sound board" available in the lumber department of your big box stores. Using thermal insulation to muddle sound doesn't add up. My neighbor, a drywaller, put it up throughout his condo unit then drywalled over it. You could just screw it directly into your ceiling then add drywall on top of it. Electrical boxes would need box extensions but this is a lot easier and more to the point than trying to shove thermal insulation into narrow spaces filled with pipes, vents, conduit, romex, and maybe some speaker or other low voltage wires....and which only mitigates heat loss with a bit of sound insulation. Go for the real thing and don't let those cloggers get you down (sorry Geico, or whosever ad that is on tv)...


What type of insulation can be used near knob and tube wiring? I have a house build in the 1920's.  I recently had a HVAC system installed, and i have to insulate my actic (Unfinished).  The three bedrooms and one bath on the floor below have a center ceiling electric light, wired with the original knob and tube electric.  What would be the best form of insulation around this area of the attic?

None. K&T was designed to have an air space around the wires. If you fill that space up with insulation--any kind of insulation--you're defeating that part of the design and causing a major fire hazard. Keshlam is right--the best solutions is to bite the bullet and have the house re-wired. Then you can install whatever kind of insulation you'd like, including in the walls, which right now are most likely empty and uninsulated--another consequence of K&T wiring.


Using indoor only power adapter outside I'm setting up a mineralization unit for my pool. The unit came with a 12V1A power adapter which says Indoor Use Only on it. At the same time, the instructions say that the unit should be powered using an outlet that's wired directly into the timer for the pool pump, so that it only operates when the pump is cycling the water. I'm having an electrician add an outlet with a weatherproof cover. My question is, is having the power supply protected by a weatherproof box the same as using it indoors? I imagine the box protects against moisture. But what about heat and humidity? I cant seem to find a similar power adapter that would be rated for outdoors.

Those waterproof covers are only rainproof. They are open at the bottom for the cords to go through so they are not moisture and humidity proof. Outdoor rated cords have a heavier, much heavier, insulation to protect them from the outdoor environment, sun, UV, animals,etc. The male and female ends are also insulated heavier and are of higher quality. Connecting to a weatherproof box is not the same as indoor use and if the outlet is outdoors, it will have to be GFCI protected.


What is simplest strategy to map circuits to breakers in the panel? My breaker box is very poorly labeled and I want to figure out which circuits may have overloaded (or close to it) and which could reasonably handle a little more.

In the past I have just tried flipping one of the breakers and then running around the house flipping switches and trying receptacles.  Surely there is a better way?

If there is a reasonably priced tool that would make this a lot easier I would consider it.

I tried one of the breaker finders, but it was worse than useless. So my solution was simple. I took a piece of paper and drew maps of every room in the house. On the map I located every outlet, light switch, etc. Then I turned off each breaker one at a time, and tested every outlet in a room, every switch. It helps to have a few items to plug into different outlets so you can test more than one outlet at a time.

For some boxes, you must be careful, as you may have two circuits going into the box in some cases. And some outlets may even be split in two, or some outlets are set up as switched outlets. Identify all of these things, taking careful notes on the map.

This all took little time, and perhaps even less time than it would have taken with a breaker finder. In the end, I have those maps, so whenever anything needs doing, I pull out the map and shut down the correct breaker easily before I do any work. Even so, I STILL check the box to test if the lines into it are dead. You can never be too careful with electricity.


Is it okay to throw paper towels & rags with mineral spirits in the trash bin? Newbie painter here. Is it okay to throw rags and paper towels that soaked mineral spirits into a plastic bag and then into the trash can?

No it is not safe. The plastic bag will most likely make it worse. I have seen just an open pile of rags (not bagged) smoldering in a jobsite waste can at the end of a work day. I removed them and set the pile in the yard just to be safe, it was a pile of ashes in the morning.


Does running a dehumidifier with an AC unit save money? I've done as much research as i can an every site i hit seems to have a different story on my question: "Will a dehumidifier save energy while running your AC through the summer"?

The ones that say "yes" pretty much reason that you usually can raise your thermostat a few degrees because of the lower humidity it will "feel" more comfortable. While they reason that yes AC do dehumidify also but it will put less of a load on your AC system.

The ones that say "no" say AC units doesn't run optimally when a dehumidifier is running (they don't go into details). Also, by design, dehumidifiers heat the air. How much of a difference that makes, i don't know.

That being said dehumidifiers do pull quite a bit of energy (i'm sure not NEARLY the amount of an AC unit though).

I live in zone 5 (central IL). Hot/humid summers and cold/dry winters. I don't need a dehumidifier for the winter (we actually need a humidifier then).

Also, as a lot of you probably already know, current dehumidifiers are some of the most unreliable appliances you can buy. Its one of the few things i know make sure i get an extended warranty for. I'm on my 3rd unit and, one of the reasons i'm here, is to find out if i need to budget for another one. Sure i'm sure there will be days when i could not run the AC and just run the dehumidifier but i don't think there will be enough of those days to warrant a dehumidifier if i really don't need one.

A dehumidifier is about the same as a window AC unit with both parts in the house, for most purposes. They draw just as much power as an A/C unit of similar size (or more if they happen to be old and inefficient.)

Given that the required energy labeling on A/C units tends to promote a degree of of paying attention to that, and it's much less clear on dehumidifiers, I suspect that in many cases the A/C of similar size will actually use less power - and it doesn't make your house hot.

Sure, comparing a room dehumidifier to a whole house A/C, the whole house uses more energy - but it also removes more water from the air, and cools the house. It would only be ANY savings if the whole house was LESS efficient (power in to water out) than the dehumidifier. If you are running the A/C as well, you are also ADDING the heat from the dehumidifier to the A/C load.

In short, run the A/C, don't bother with a dehumidifier unless you have a job that a dehumidifier (alone) is suited for; Which it sounds like you probably don't.

If you want to get "something like that" without the downsides, when your water heater wears out, consider a heat pump water heater - free hot water with a little A/C, or free A/C with your hot water. Still rather expensive, but sometimes with large rebates available too.


Identify type of switch Can anyone identify the type of switch this is? There are 4 connectors at the bottom and 3 at the top.

I've already purchased a 2 gang 2 way switch which turned out to be the wrong one (it only has 2 connectors at the top).

I'm in the UK if terminology differs from other countries.

What you have is a four way switch and a three way switch. The three way is the one with the three wires, the four way is the one with four wires. Take note of the 'point' wire on the three way if you intend to replace it, you should find some marking on the back of the switch that indicates which leg that is.

As said in comments, it's unusual to see those in the US, but they are common in Europe and Asia. Akari makes an almost identical line of 'slim and stackable' wiring devices, except slightly smaller, if you're looking for an approved / listed replacement.


Finishing basement... level floors with SLC or install stud wall first? Basement floor isn't too far off... wondering if I should get the stud wall done first or level the floor first....

You will have better surface to screw/nail bottom plate working on original concrete as is. You can and should always level before getting floor done.


Attach 2 wooden broomsticks to make one long broomstick I have a branch cutter with a hollow handle. Something like this (except a little more simple):

Now buying long poles to suit the cutter were quite expensive so instead I drilled a hole in a regular wooden broomstick and inserted it into the handle of the cutter then fastened the stick inside with nut/bolt.

Problem is: the stick isn't quite long enough!

Is there any viable way to attach both sticks together (one on top of the other) to increase the length of the stick in a way that it will be strong enough to use to prune date palm branches?

You can get long and/or extending poles usually sold for painting, but the standard screw on the end works for mops and brooms and accessories sold for such poles.  Some broom handles have the same screw socket in the end so they can be combined easily.

I have one made of fiberglass that extends to 20 feet. I used it for painting, and then for picking fruit, drying pasta, and any number of things.


Finishing around brick veneer fireplace I am installing brick veneer around a fireplace and on the hearth, but am having trouble thinking of the best way to finish it along the floor.

There’s about 3/4 inch clearance between the floor and the bottom of the brick. I’ve tried cutting slices off the edge of other veneers and staggering them (as a standard brick pattern such that it would look like it’s going into the floor), but cutting them to 3/8 thickness without breaking has proved difficult. I’ve also thought about putting down a square dowel and/or shoe molding, as well as cutting the face of the existing front corner bricks in half so that I could place larger slices along the floor (the hearth is not mortared down yet). Painting/refinishing cut sides is not a huge deal, as matte acrylic paint seems to work well.

Any suggestions on how to give this a nice finish along the floor? Thank you!

I would go with a piece of square trim that would fit under.  stain it to be the color of your floor or perhaps darker (or black).  It would cover the board but it would have a finished look.  I'd also try to make it thin enough so that it wouldn't stick out past the brick.


How to find the concrete beam in a sandy block ceiling? I want to hang a ceiling fan at my apartment, where the ceiling is made mostly of a sandy material. How do I find the concrete beam going through it, assuming I do not have access to the blueprints of the house?

Have you tried a stud-finder device? They are normally used with thin walls to find the wooden studs behind the walls. I think they are really ultrasound devices and they just look for the return time. They should work on any homogeneous material, as long as it's not too thick.


Washing machine - Will not agitate I have an Electrolux (Frigidaire) stacked washer/dryer combo that is not agitating. The control circuity, lid latch, motor, and belt all seem to work. It fills, drains, spins, and with the lid open at the agitate cycle, and the switch manually engaged, the motor spins. Grasping at straws, I pulled the agitator itself off, and the "drive block" (spline gear) which is lose enough to turn does not turn.

I note that the transmission itself is stationary while the washer is in agitate cycle, but is free to and actually spins itself while in the spin/drain cycle.

It isn't clear at all how the transmission is signaled to engage the drive block, vs spinning the tub.

Is there any more reasonable steps I can take to diagnose and repair?

For clarity, my machine is an Electrolux mex731cfs1

Here's the Sears Help for your washer if it "Won’t agitate or spin."

It says it could be:

The lid lock switch
The washer drive motor
The washer timer

They also have blown-up diagrams of each assembly.  You can buy the replacement parts there.  (Or get the part number and search online.)

You can find the wiring diagram and user manual (not the repair manual) here.

Here is the service manual.  It is $9.95.  I haven't verified the helpfulness of this.


Adding insulation to basement that already has vapor barrier I have leftover insulation from doing my basement, little bits and pieces.

In between the joists on my basement ceiling it is insulated with vapour barrier already from when the house was built.

Will condensation form if I put all the extra pieces against the vapour barrier on the inside of the wall but do not put a second vapour barrier? Or will it be fine and help my house stay better insulated? Or is it a complete waste of time.

It just seems like such a shame for all these smaller pieces to go to waste.

Insulation is always installed as such:

Warm side | Vapor/ Moisture barrier | Insulation | Cold side

You ONLY want a moisture barrier between the warm side and the insulation, because warm air holds onto more moisture than cold air, and when warm air meets cold (air, wall, whatever), the air has to let go of that moisture as it cools, forming condensation.  The moisture barrier prevents that moist air from getting into the insulation where cold and warm meet.

If you put insulation on the wrong side of your barrier, the moisture will form in the insulation, and as Shirlock said, if you create TWO layers of barrier, you create a potential moisture trap.


230v Electric Cooker is the wiring correct this way ?
in the plug, should the brown cable be wired in the R1(L1) or T3(L3)?

Presumably the socket for this appliance is a three-phase one to physically match the plug you show.  (Otherwise, obviously, you could not plug it in).
If that socket is actually wired with two or three phases of power available, then your appliance plug is not wired correctly.   You could remove the jumper shown in the first picture and make use of additional phases via the unused grey and/or white wires in the power cord.
On the other hand, if you only have one phase of power available at this location, or perhaps in your home entirely, and a 5-pin socket was installed just to suit appliances like this one that come with the three phases jumpered as shown, then your plug is wired correctly.
Additionally, referring to the diagram in the first picture, if you are powering the appliance via one phase, as currently wired, you should make sure that power cord (which in fact has 5 conductors) contains 4mm^2 wires.  I cannot tell from the picture how fat the wires are.  If they are smaller than 4mm^2 AND you only have one phase of power available at the socket, you should entirely replace the power cord.


How to fill recess in fireplace before tiling I wish to tile a fireplace pictured below

The brickwork has a recessed area directly above the firebox (pictured below)

This recessed area measures 28" x 8" x 1-1/2"
I wish to tile over the recessed area flush with the rest of the fireplace front.  In other words:  Remove the recessed area.  My thought is to fill this area with a non-combustible material like durock.  Not sure what the best material would be, though.  Seems to me that it would be easier to use something thicker and lighter.

I was also thinking of making a mold and filling it with a high-performance cement.

Any suggestions would be appreciated.

Yes, I agree with you. Use three layers of 1/2" Durock. Attach all 3 plies at the same time to the brick with 2-1/4" Phillips Tapcon concrete screws.

Durock is certified as non-combustible tested to ASTM E136, “Standard Test Method for the Behavior of Materials in a Vertical Tube Furnace at 750°C” and therefore is acceptable in use as a fireplace facing.


What is the danger of reversing the polarity while connecting a dishwasher to the electrical service? What is the DANGER, if any, of connecting the white neutral line of the dishwasher, to to black hot line at the power source--- and of course similarly connecting the black hot line of the dishwasher, to the white neutral line at the power source. Now I would not do this, but a fellow at the store said it would not make any difference. In either case the copper wire would go to the green ground screw. I seem to remember from somewhere that if the wiring were to be reversed as mentioned above, that a person touching both the dishwasher and maybe a sink or ground of some sort, that they could possibly get a big jolt of electricity.

Reversing "polarity"* (swapping the hot and grounded/neutral wires) presents no danger to the equipment on an AC circuit. In terms of electrical properties, the conductors are the same. The current switches direction 50 or 60 times each second, and the equipment simply cannot tell the difference between the two conductors. Here's an interesting article in the Electrical Engineering Times about neutral wire myths.

Safety to humans is a different matter. In most of the world, common household current is single phase power, with a “hot” conductor carrying line current, and a grounded “neutral” conductor carrying the return current (120V in North America, 230V in Europe, 100V in Japan, etc.). In North America, the single phase is actually 240V split into two 120V legs, and there is no neutral if you use 240V, but let’s sort of ignore that for now.

The hot/line conductor is dangerous if you touch it, while the grounded neutral is normally safe.

If a device or appliance uses a single-pole on/off switch, so it only breaks one conductor, then it’s dangerous to switch the neutral. If you switch the hot conductor, it de-energizes all the wiring in the appliance. However; if you switch the neutral, it leaves all of the wiring in the appliance energized. If you touch it, or if there’s a fault and you touch the appliance housing, you could be electrocuted even if the appliance's power switch is off.

If an appliance has a two-pole on/off switch, then it will break both conductors at the same time. Consequently, no matter which order you connect  the wires in, throwing the switch off will completely de-energize the appliance.

* Polarity: this term is not terribly accurate. It's "polarity" in the sense that the hot conductor on a hot/neutral circuit is connected to one pole or the other of the smaller coil in the transformer outside (the neutral is connected to the center of the coil, not to either pole). But there's no such thing as a correct direction for current to flow on an AC circuit, since AC current changes direction constantly. So this is not like the positive/negative polarity of DC current from a battery.


How to align PVC pipe to metal electrical box I'm transitioning outdoor PVC conduit through the rim joist and into a metal box. The problem is that my holes in the box don't quite line up with where my conduit comes in. Is there an easy way to adjust the alignment or a type of box that is maneuverable to line up with the conduit? The location is through the rim joist and the box is between the floor joists.

You can make a transition with a piece of carflex (LFNC) or sealtite (LFMC) to make a flexible offset in your conduit. Use a PVC male adapter and a sealtite connector to make the transition. Some hardware stores will already have small piece of flex premanufactured. The only problems with this is sometimes this can look pretty ugly, and pulling through may get a little tougher. Be sure and bring along some pulling lubricant to help.

Good luck.


Do I need a lead-free water hammer arrestor for washing machine? Our washing machine hammers really hard and shake pipes through the house. I've installed a few more supports for the pipes in the basement and that has helped, but it still hammers really hard and we want to quiet it down but also be sure that there is no damage being cause to the piping or the machine.
There is a cheap option that might make sense to try first (I'll need two - hot and cold) that is not lead safe. At 4x the cost of the above, the lead free option that I've found is to use a hammer arrestor and threaded fitting together.
I don't plan on drinking water out of my washing machine, but my concern is that without a check valve between this and the rest of the piping. Is it best to go with lead free so as to prevent contaminated mixing back into the rest of the house?

If you are concerned about saving money, get the "not lead safe" one as this is a non-potable water installation.

If you are paranoid about lead and the remote possibility that a significant amount of lead could backflow from the cheaper arrester installation into your drinking water then spend the extra money on the lead-free certified product.

This is, in my opinion, an example of warnings gone awry where the actual danger is so remote as to be implausible.  I doubt that the less expensive product contains any lead at all but if you feel the need to be 100% certified then why are you quibbling about a few dollars?


Strapping to level ceiling before putting up rock——code? I’m considering putting up 1x3 strapping (rather than steel beams)to level the ceiling in my kitchen (century home) before putting up rock. It is out of level between the joists anywhere from 0 to 1/8” to 1/4”. The joists run between 14”, 16” and 18” OC. The ceiling area is about 390 sf.
So my main question, that I can’t find in the building code, does this meet code in a kitchen.  I guess one of the main concerns is around fire code.

Also, I’d like to use 1/2” fire rated rock rather than 5/8

This is in Ontario, Canada.

(Those scabs you can see was the original builder attempt to level them)

An added question, how out of level is acceptable to not be visible?

Not a full answer, exactly, but enough additional comments to the answer by @Ack that I thought I could get away with it.

Just to reiterate, you don't need fire rating, unless the kitchen ceiling happened to abut a different unit within the house. Then I'm not sure.

1/8" - 1/4" out of level is pretty subtle. It would be noticeable if there was crown against the ceiling, or if your upper cabs were close. It would also be noticeable if it was 1/4" inside a couple of joist bays. If you didn't strap the ceiling, you could fix the cabinet/crown problem with mud.

Here's an answer I wrote a while ago about strapping ceilings. (Paradoxically, it wasn't the right answer to the question, but it fits your application.) SE answer on strapping ceilings. Strongly suggest you lay hands on a laser... I'm not going to go back and edit my old answer, but at this juncture, I'm not sure how I'd do this efficiently with a level. And definitely use 1x4s. They won't cost much more and give a lot more wiggle room for seams.

Edit, to your additional question, "how out of level is acceptable to not be visible?"... If you have crown up against the ceiling, or upper cabinets within 1", I'd say you want to be within 1/8" for the whole ceiling. If you don't have that situation, I'd shoot for 1/8" within any given 3' span. (It really isn't hard or time consuming to get a ceiling dead flat...)


Networking in an Old House So I have an old house (circa 1790) that I'm trying to install data cable into. It has 2 floors for living, and attic and a basement. The issue that I'm running into is that there are only a few places that reach from the basement (where the modem and switch are housed) to the attic and they all already have either plumbing or electrical wires running through them, and the walls are all plaster, which I don't want to mess with to make new routes. There's on spot in particular that would be ideal for getting a wire through (I managed to get fish tape from the attic to the basement with relative ease), but there is an electrical run already there. However, there is also a derelict coax cable already installed there as well, which was able to transmit HDTV with no problems when it was still in use. I'm wondering if that is a good enough sign that shielded Cat6 would perform ok there, or whether I should look into either fiber or finding another path down. The run would be about 70-80 ft total with 30 ft or so alongside the electrical. Thanks for your input!

Side note about the electric runs: the wires that are not in a conduit are only to connect the attic lights, which are seldom on, and then there is a shielded conduit which houses the power for the HVAC system up there.

Unshielded twisted pair will perform fine along side 120V 60Hz wiring.  Don't bother with shielded, it won't pull as easily and is more expensive and isn't needed for you.  Twisted Pair will not have problems because of differential signaling.  Plus you're only talking about 70-80 foot run,  you could still run CAT 5e and get Gigabit.  I'd be surprised if you see a single error on the interface.  Modern Ethernet is amazingly resilient.  This isn't like Thinnet, tokenring, or old coax days.

I'm not saying its to code, but you don't need to worry about EMI at least.

UTP Cabling and the Effects of EMI


How do I optimally cut a bolt to length? Once in a while I need a bolt of exactly the right length and it is not one of the lengths available in stores. So I get a longer bolt and cut it to length. Here's the procedure I follow.

I screw one or several nuts onto the bolt so that they are between the bolt head and the future cut. Then I grip the bolt in a vise and cut it with a hacksaw. Then I trim the edges with a file to get them to something like 45 degrees. Finally I ungrip the bolt and unscrew the nuts and that cleans the threading of any loose metal.

What I don't like is trimming the edges requires a lot of tedious work and usually the edges won't be as clean as they were on the original bolt and so the bolt will sometimes get stuck when I start to screw a nut onto it and I'll have to remove the nut and try to screw it again. This it not a problem when the connection is to be permanent, but is definitely a problem when it has to be disconnected and connected back rather often.

Also it's quite problematic to have a cut perfectly orthogonal to the bolt axis because the threading helps the saw blade to slightly drive away. This is not a major problem, but still would be better to avoid.

Is there a more efficient procedure for cutting bolts to length that would yield cleaner edges and more precise cuts?

After cutting the bolt to length, use a stationary grinder instead of a file to clean up your work. With a grinder, it's easy to square up the end of the bolt and apply the chamfer that you want.

Just be careful, especially if the bolt is shorter than the grinder's table. If the bolt is short, use a pair of vice grips to hold the bolt during grinding. And remember that the end of the bolt is going to be very hot after grinding!


Do these plastic molds exist? I want to make a few concrete pavers, so I started looking for a few tutorials, and found this youtube video.

In the tutorial, he uses a plastic mold where he pours the concrete. Something like this:

Do these plastic molds exist? I searched amazon and home depot, but didn’t find anything.

On the recommendation of a neighbor, I purchased a set of five molds for US$99 with free shipping. The size for my bundle was 10" x 18" x 1.5" but they have many different sizes available. The web site has been upgraded since I purchased. The molds appear to be high quality and my neighbor has nearly paved his entire yard with the casting he's done.


How do I replace oven insulation that has been soiled by mice and smells bad? We've had mice work their way into the oven insulation of our standalone range and now it stinks when we turn the oven on.

Looking around on the web suggests that replacing the oven is the most common solution, but that seems extreme!  Any suggestions?

(In this case the oven is a "Viking Professional" (bottom of the line) 4 burner + oven freestanding range. I haven't yet been able to pull it out enough to check if it has removable panels or been able to find a manual online.)

I'm guessing the answer will be something like:

locate the manual for your appliance
remove access panels
remove insulation while being careful about ??
remove insulation that is "stuck" by doing ??
replace with new insulation from ??
put it all back together and test as follows
in general be careful of ??

And, perhaps this is too specific to the brand of appliance? It would be useful to know which brands are more amenable to DIY repairs of this type than others.

I'm so sorry for your loss.  A Viking is a terrible thing to waste. Disassembling a Viking oven/range is not a job for a DIYer.  Look for a restaurant supplier in your area or a  Viking dealer to get a competent tech to do the work and bite the bullet and have it fixed right.  The insulation is not something you can buy at the local Home Depot. It uses a specialty high temp spun fabric insulation . If the job is not done properly, it will be a FIRE HAZARD!!!!  This is a  safety issue not worth saving a few bucks on. The Viking is worth saving if you can.


What is the technical term for this corner cupboard? I am trying to learn what this small blue cupboard on the left side of the table is called? It's a corner cupboard but I am not sure what the technical term is:

I am not certain what you mean by a "technical term" for it.  I would call it a corner hutch or a corner display hutch or maybe a corner bookcase.

Why corner? Because it is shaped to fit in a corner.

Why hutch? A hutch is sometimes something that sits on top of a bureau, table, desk, or other piece of flat-topped furniture. However, hutches can also be a free-standing shelved storage units with doors.  The impression people have of "hutch" will vary by region.

Why bookcase? It's got books on it.

I can tell you also that I would not call it

a cabinet: Cabinets usually have doors and are wall-hung or sit on the floor.
a cupboard: Cupboards are usually wall-hung and contain dishwares or foodstuffs
a curio cabinet: these usually have mirrored backs and glass doors
a display case: see curio cabinet. These usually have at least glass doors.


faint led strip glow with negative voltage levels when turned off I'm kind of stuck. I build a ceiling lighting in a smaller room using led trips in a rectangular shape with aluminium channel for better heat dissipation. All went well, until a couple days ago in the evening I found that my led strip has a very faint light when turned off (only visible during the night in nearly complete darkness). In the last days I've been there and back and couldn't find the cause.
Wiring:

Equipment used:

V-TAC PSU 230V input, 24V output (max 150W)
SkyDance SD T1-1(White) wall controller (only used as a remote)
SkyDance SD V1 controller (controlled wirelessly using the wall unit)
V-TAC 700led/m led strip with a total 4.6m length (21W/m)

I'm using a multimeter to read voltage levels and all seems to be well until I turn the controller off. Setting the brightness to max levels on the SD-V1 controller, the input voltage is 23.8V, the output voltage is 23.7V, led strips light up as they should. No flickering, nice even light.
When I turn it off however, the I'd expect the voltage to drop to a 780mV range. Instead, I read -11.7V and the led strips remain on with a very faint light. I've already changed all equipment  tested them separately everything works. If I disconnect any led strip segments they all behave the same (negative voltages while turned off). I took a smaller piece of the same led strip, disconnected the 4 strips and connected only the small piece and surprise, when turned off the voltage dropped to the ~780mV range with no faint lighting.
Any idea what can cause this behavior? I can eliminate the faint glow by adding a capacitor at the output of the SD-V1 controller but I'm rather interested what's causing it. I checked everything already and couldn't pinpoint any problems.

Solder points are insulated using hot glue
led strip segments do not touch eachother
cabling has no apparent damage
cabling continuity is fine
distance from "high" voltage lines (230V) is ~60cm and I'm using insulated cables

Talk to the manufacturer
This is an artifact in the behavior of the dimming controller (SD-V1).  There aren't any stock answers on what to do about this, because controllers aren't supposed to do that at all.  It is a unique, um, characteristic of that controller.
The manufacturer will be able to advise whether this is a defect vs normal behavior, and what options they can recommend to eliminate it.
Understand the way this type of dimming is done.  It is not like the "triac dimming" used for AC power light bulbs.
How PWM works
24V DC LED strips (and 12V ones also) use "PWM Dimming".  It does not vary the voltage or current.*   It turns full voltage on, and off, hundreds of times a second (frequently enough to avoid any visible flicker).  It varies the "duty cycle* (percent time "on") based on the dimmer setting; i.e. "Pulse Width Modulation" or PWM.
The upshot is that under PWM, when the lights are on, they are on at full power/brightness and illuminate at full spec.  When they are off, they are off.
PWM is preferred because it makes different lights (or the same lights with manufacturing variances) perform equally at every dimming level. If they are balanced and look good at 100%, then when you turn them down to 30% they will still be balanced and look good (because they are still on at 100%, just 30% of the time).
So what's going on here?   There might be a leaky MOSFET inside the controller, but I doubt it.  I suspect the MOSFET switches just fine, and the software in the PWM controller is choosing to turn the MOSFET on and off at a low duty cycle e.g. 1%.
And I suspect that is happening because of a communications snafu, either internal to the controller's design, or because of the way the dimmer/remote communicates with the controller.  That's why I recommend consulting with the manufacturer.
So what's up with the weird voltage reading on the DVM?  I suspect it is a reading error from a simple DVM, which is made for flat DC, or sinewave AC.
Capacitors, no
However, PWM systems need to be able to distribute that sharp square-wave signal to all lamps. Capacitance is the worst enemy of PWM light wiring, because it muddies the PWM square wave -- too much capacitance will reduce it into a "varying voltage" system, and that does not perform well with LEDs.  It may also burn out the controller, because it is not designed to drive into a capacitive load, which will draw inordinate amounts of current to charge the capacitor.
The capacitor you mentioned acquiring, "Konoq LED Adapter Capacitor", is for a totally different problem space: AC Mains dimming using the "sinewave-clipping" method with a triac. (which obviously doesn't work on DC). It cures a problem with simple 2-wire (no neutral) triac dimmers which need to leak current through the bulbs, but the power supplies in screw-in LED "bulbs" don't permit that.  That product definitely is not made for PWM dimming.
While you are talking with the manufacturer about the "won't go off" problem, I would ask them about the capacitor solution.  I am fairly sure they are going to say "no, no, no".

* It does not vary voltage, because it would be ineffectual: LEDs are highly non-linear, and dimming would not occur linearly from 0-24V as one would desire.
It does not vary current because of the construction of 12/24V DC LED strips, which are comprised of many, many series strings of 3-6 LEDs + a resistor, in parallel with each other. Many strings or other types of 12 or 24V lighting can be paralleled as well (in the normal way).  That works great with PWM, but a variable-current approach would cause current to favor some parallel paths over others (due to design differences of dissimilar lights, or manufacturing tolerances of similar ones).  That would cause the lighting to be uneven, with visible differences in dimming between different series segments or different types of light.


How do I know when to switch to a finer grit when polishing marble? I am polishing a marble shelf with pads impregnated with a resin containing diamond powder (it has some advantages over sandpaper, but otherwise works in a similar way). I used grit 50 to remove scratches and stopped when I couldn't see any more scratches.

Then I use grit 100, 200, 400, 800 (maybe more) to get a nice polish. But it's hard to tell the difference before and after grit 400 (for instance) by touching or looking. How do I tell I've spent enough time with this grit and I should switch to the next, finer one (in this example, grit 800)?

The final step will be a sealer.

I would suggest that to get a really smooth polish you will be using sand paper or polishing pads with grit numbers as fine as 3000 or more. The general advice is to switch to the next finer grit when you no longer see any remaining grooves or roughness left by the previous grit.

You may need to experiment with looking at the area that you are polishing carefully to see how it is coming along. It will certainly be necessary to really clean up the area and remove all the dust and particulate that you have created. A bright light shining on the surface that you then look at from an oblique angle can help you to see the fine details. If you are using the dry polishing technique it may be useful to wet the surface to see how your work area compares to other parts of the marble that were previously polished.


Doorway transition between hardwood and floating bamboo with different heights We have hardwood in our whole main level except for a study that had carpet.  I've pulled up the carpet and have been replacing it with floating click bamboo.  I'm trying to figure out what to do with the transition through the doorway to the "traditional" nailed hardwood.  I know that floating bamboo needs to have room for expansion, which means a half inch gap between the wood and any wall or other object and it looks like this is often solved at doorways with a T molding between the two types of flooring.  The challenge I face is that the bamboo is about three eights of an inch lower than the hardwood floor and (from what I understand, which could be wrong), T molding works when both sides of the transition are the same height.  I'd love any guidance, feedback, advice on how to deal with a transition that has slightly different heights.  Thank you!!!

You probably want a threshold molding.

https://www.preverco.com/en/accessories/mouldings


How can I use these "closed" power outlets? I just bought a new home. It seems that the builder had some outlets open (where I can plug any devices), while some are closed (I can't plug anything). Is there a device I can rent or buy from any hardware store that would allow me to pop the closed outlets open SAFELY? Also, some of the outlets says "protected surge" on them.

The receptacles that say "protected surge" are either surge protection receptacles, or are protected by a surge suppression device in the panel.

As for the "closed" receptacles, those are most likely tamper resistant receptacles.   The guards should move out if the way when you plug things in. The guards only move when they are both pushed simultaneously, so make sure you're inserting the plug straight. If one blade touches first, the guards may not move. Also, the first time things are plugged into these receptacles, the guards seem to be a bit stiff. Wiggle the plug, and try a bit more force. After the receptacle has been used once or twice, it will be easier to plug things in.


What is this small hollow metal cylinder? I've bought a flat-pack bed second hand, and it has one part missing. There are two boards I need to join, and according to the instructions I should hammer a short (about 4 cm) hollow metal cylinder into the hole in one, and then push it into the other, and then put a bolt through the cylinder (and fix it in place with a barrel nut). The cylinder is the missing part and I'd like to know what it's called so I can find a replacement. It's smooth both inside and out.

Here's a sketch of the situation in section, which is hopefully clearer: (I've omitted the barrel nut)

"Sleeve" or "Bushing" (sleeve being closer to correct for this application, but having both in hand will give you more things to try at the hardware store.) A section of pipe or tube might well do the job in the "not precut to length" materials section.

Are they all missing, or do you have one or more you can take with you to match?


Can fill hoses be reused for a new washer? I'm finding that major appliance retailers and manufacturers insist that a new washer requires new fill hoses. Used fill hoses cannot be reused, it is claimed.

Of course I have to wonder about this since (a) many (most?) units do not come with the required hoses and (b) the folks dispensing this advice would happily sell me new hoses. If a new washer requires new hoses, what is the justification for not including them as a matter of course?

Can old fill hoses be reused? If not, why not?

"what is the justification for not including them as a matter of course?"

there are numerous choices when it comes to type and length of hose. Cheaper rubber hoses, more expensive stainless steel braided jacket rubber hoses, lengths from 4' to 12' long, etc.

"Can old fill hoses be reused? If not, why not?"

They certainly can be reused. If you are confident enough that they are in good shape then feel free to use old hoses (you should replace the washers at the end connections).

The downside is that, unless you turn your water supply valves off every time you leave your house, an old hose that fails can easily cause catastrophic flooding of your home. You need to make your decision based on a risk assessment putting the cost of new high quality hoses against the chances of and cost of a hose failure.

I bought brand new supply valves with quick 1/4 turn ball-valve construction to facilitate easy shut-off, and the best quality braided stainless hoses; and I shut off the valves whenever I will be gone for more than a day, because I do not want to come home to a flooded house.


Why is a light switch is buzzing at audible volume? just noticed that a light switch (mechanical, not a dimmer; 220v 50hz) is buzzing at audible volume (can hear in 20cm), when both keys are on (first: traditional lightbulb, second: 23w energy saving bulb - with all that electronics inside).

Didn't opened the switch so dunno how it is wired (common phase.. or a common ground - if an installation point is powered by two wires, a drunk specialist may have used them the wrong way), it is known that this connection is split from wall sockets/main room lightning (yes, two switches outside the house!).

Problem:

pressing key 2: energy-saving bulb enabled, no sound
2, then 1 (normal bulb): sound.
2, ..some time, 1: sound
1, 2: sound
sometimes, no sound at any combination.

Guessing that a bulb is possibly broken and sends a high-freq noise that forms an arc..
Unfortunatelly can't get a single normal bulb today to test if it forms a noise, too.

There are a couple of possibilities: the most likely is that the switch is worn and should be replaced.  If the switch makes a good connection sometimes and a bad connection at other times, you would hear the noise only occasionally.

If your local laws allow you to do the work yourself, I think this would be an easy task.  The steps would be (at least in the US where I am):

turn off the circuit breaker;
remove the switch cover plate;
double-check that there's no voltage at the switch in both on and off positions;
unscrew the wires from the switch
screw the wires onto the new switch
reinstall the new switch and cover plate.

Another possibility, but much less likely, is that there's a loose connection between the switch and one of the wires.  The steps to fix this would be the same as for replacing the switch, but tighten the screws on the wires instead of removing the wires.


Wiring Smart Switch to Always Be On and Power Switch When using an Insteon 6/8 scene switch with smart wifi lights like a Lifx/Hue, would like to program the on/off buttons to a scene to turn the smart light on and off via software. That I can do.

However, need to have the switch wired to always be on. If I plug the line directly to the load with a nut, the light would always be on, but then no power would be going to the switch, I need power to the switch.

Is it as simply as attaching the line from the switch to the line from the wall and to the load going to the light together? And then capping off the load wire coming from the switch? In theory that seems to make sense, but would that work?

And yes, if house ever sold, would need to rewire back, or if ever need to turn off power to the light would need to flip the power breaker downstairs.

To note, the switch has a ground wire and neutral wire, both which would leave hooked up as is. Also this is a one way switch in a house built in the past 10 years.

Yes you can.

Move the load connected to the red wire of the switch to the same wirenut as the black from the switch.  Cap the red on the switch unused.

With that change the load is always on, Scene A can be used however you wish progmatically.


Should I remove moulding before adding a plaster ceiling? We have an 85-year old house with textured ceilings.  We had a plasterer advise us to install new plastered ceilings over the old ceiling; if we do so, without removing moulding, the new ceiling will cover half an inch of the moulding.  But if we do remove the moulding, we are worried about the risk of damage to the wall.  Does anyone have experience with a similar issue?
Edit:  Sorry, I should have been more precise:  they are going to but a blueboard and then a skim coat of plaster.

Yes, you should remove the trim before the ceiling is done.

Yes, some and possibly a lot of the material will get damaged if you have not done it before. Even a pro will crack some, but a pro will know how to repair it too. Sometimes it is better to get a new molding that closely matches the original.

Yes, the wall will get damaged too here and there but the same crew doing the plaster can mud in the damaged spots too.


Outlet is Live, but Main is OFF? Ok, so I am trying to replace the light switches in my garage; I shut of the breaker, but the switches were still reading voltage using my non-contact sensor; I go back and switch off other breakers, assuming the breaker was mislabeled; still, it senses voltage. I shut off every breaker in the panel (except the Main), and it still reads voltage.  [scratching head further]

Heck, I shut off the Main.....that surely will do the trick!  Voltage continues. [puzzled and generally concerned].  Here is a short video clip of the circumstances: https://drive.google.com/open?id=0B6sfNdtoREigd2kyZU4yRWR0b3M

Any suggestions???

Thanks,
Tom

As mentioned above, a high-impedance meter can detect the very small amount of electricity coupled across the breaker by capacitance from outside power lines running parallel to the house... but as also mentioned, someone could have bypassed the breaker, so you need to check that there's less than ~20 mA available.

Put a small (1 or 2 watt) night-light across the circuit, with the breaker off... if it lights, call in an electrician to fix this dangerous condition. Note that neon lamps glow visibly with only a mA or two, so are over-sensitive for this application.


T12 Fluorescent ballast bypass not working I have a solid state electronic ballast that houses T12 Fluorescent tubes. Recently one of them burnt out and I want to change it to LED fluorescent tubes. I bought 2 Phillips universal fit tubes. I decided to remove the ballast to get real energy savings.
I followed multiple YouTube videos on the bypass process, but it isn't working for me. Every time I turn on the lights, nothing happens.
Can someone please point out what I'm doing wrong?
Here's how my current setup looks like

YouTube Videos I referenced:
https://www.youtube.com/watch?v=wqU3nuxc5w8&ab_channel=StarLed
https://www.youtube.com/watch?v=TPCI9eILwoA&ab_channel=motoforlyfe

Looking at the Phillips web site it states replacement tubes no rewiring needed.
I do not see anything that states universal. Universal usually have the info on single ended or double ended.
Replacement lamps require a functional ballast.
This is why I say UTube can get you in trouble sometimes guys do not know what there doing. Some times they make it look like they did something getting you to follow their instructions blindly and blow things up.


Electric sockets directly under water pipes under the sink - Safety I am in the process of buying a new bungalow. However I have noticed that there is a standard double 13a socket below the plumbing under the sink which is giving me cause for concern.
The builder advises it is fine as it has a cut out switch. There is no visible cut out switch so would appreciate any advice as to whether I should challenge this

I believe this is not uncommon. The circuit must be protected by an RCD (RCBO). There is usually a means of disconnecting or isolating the socket from above if the socket is inaccessible when appliances are installed.

However see NICEIC/ELECSA Guide to Electrical Work in the Kitchen

  Electrical sockets or switches should be fitted at a safe distance (it
  is recommended at least 30cm horizontally) from a sink to avoid
  the chance of water coming into contact with electricity.

  Sockets should also be easily accessible. If appliances such as
  fridges, dishwashers and washing machines are fitted under
  worktops, getting to sockets may be difficult. Ideally, these
  appliances should be controlled by a switched fuse connection unit
  mounted above the worktop where you can reach it easily.

  All new sockets in a house require protection by an RCD (Residual
  Current Device)

The Consumer Units (Main Electrical Panel) in UK homes now typically have Dual-RCD protection. You could easily check this by inspection.

You can buy advanced socket testers that would allow you to verify correct RCD operation at the sockets under your sink.

If you want, I suspect there is nothing stopping you replacing the socket faceplate with one rated for external use (with a rainproof cover which can be closed over plug-cables) - some incorporate RCD protection. I suspect most electricians would regard this as pretty odd though.

If you search for advice you'll often see something like

  Regulation 512.2.1, requires equipment to be of a design appropriate to the situation in which it is to be used or its mode of installation must take account of the conditions likely to be encountered.

I am not an electrician and do not have access to the 17th Edition. The above does not constitute advice from a qualified person. You can pay for an independent inspection and electrical installation condition report (EICR)


How to narrow a closet door opening? I have a closet opening that has never had a door on it (has had a curtan on a rod for 30+ years). I'd like to install a bi-fold or similar closet door. The problem is that the door opening is 44 inches and all of the doors I have seen are 24" or 36".

My plan is to narrow the opening by 8" on one side, or 4" on each side. Is this a good idea? If so, what is the best way to do this? Also, the wall is textured so what would be the easiest way to make this look nice with the existing wall?

This is for a house I'm trying to sell, so the cheapest/easiest solution (that isn't terrible) would be ideal.

Instead of changing the size of the opening, use a pair of 24" doors in the "bypass door" configuration. They'll overlap 4" when closed and you'll have a 20" opening when they're open.

If you want to increase the 20" opening, you can cut the doors to make them narrower and this will still be less work than changing the size of the doorway. Even garbage MDF doors can be narrowed almost an inch on each side, especially if you're not attaching hinges or real doorknobs.


Should I use round or rectangular electrical boxes for stubbing exterior security cameras? I'm building a new house and can't afford the cameras now, but I want to install the boxes on the exterior of the house and run Cat6 cable to them for PoE IP cameras at a later date. It is much easier to install boxes and cable (also the cheapest part) while the siding and drywall and insulation are not in place.

The boxes will be mounted on the wall (not under the eves), and probably about 8' off the ground so they can get faces, but not be in reach for tampering without a ladder.

But, without knowing what specific model of camera I'll get (and models will change as time goes on), should I install one-gang rectangular, two-gang rectangular, or 4" round boxes like the kind used for exterior light fixtures?

Is one type of box preferred over another, or is it adaptable later where it doesn't matter?

All the ones I've seen seem to be sized for installation on a light box.  You want to use as shallow a box as you can get away with so you don't decrease the wall insulation.  If you use the really shallow ones, you might be able to surface mount them on the sheathing over the tyvek.

Do you even need a box?  If the camera is PoE, you're running low voltage and tiny currents.

I think your best bet is to look up some of the cameras, then go to the Mfgs website, and read the installation guide.

Don't put them all at 8 feet.  That's really easy to hit with a spray can of paint.  Mind you:  Any camera is subject to a paint ball gun

You can often find dummy cameras.  These can give a bit of false security while you are waiting to afford the others, and they can mark the places where your cable comes through the wall.

Place one camera where it can read the license plate, both coming and going.

Place at least one camera where it can get a good face shot of someone leaving the house.  These cameras are much more difficult to scout, and most thieves aren't actively looking for surveillance on their way out.


Removing the smell of cannabis (not my cannabis!) Having recently purchased a house which was previously used to grow a "commercial" amount of cannabis I'm struggling to remove the smell. It seems to be engrained in to every surface, hard or soft. How would you approach the task of deodorising the property?

Grow some other strong smelling plants, lavender, eucalyptus etc. In fact many many non odoriferous plants in a space will help to "clean" the air.

It will dissipate.

Air ionization machine.

Citrus based cleaners.

Baking soda sprinkled on the carpets.


Increasing the Maximum Shank Dia There is a device in my head that I know must exist, but I can't seem to find it.

I own a drill. Kinda small. It has a small chuck so the shank dia of the drill bits that I can use is limited. Is there a way around this limitation?

I figure there must be a device that is basically a large chuck connected to a thin shank which can fit in the chuck of my drill, effectively allowing me to use drill bits with greater dias.

Links to where I can purchase this imaginary device would be appreciated.

There are bits referred to as Silver and Deming bits.  They have a smaller shank than the actual bit diameter and are available at home centers or on line. They come in a traditional twist drill configuration, so they can be used for drilling metal. If you are working with wood then "paddle" or "spade" bits will work also. You have to use caution when drilling holes of a larger diameter than the drill was designed. The drill may not have the secondary handle needed to control the torque. The speed of a single speed drill may be too high to control the bit. You may also overload and over heat the motor to the point of failure.


Finishing up the junction box Inspector said something was required in the hole that was punched out to run the romex through. (hole can not be left with just romex)  anyone know what I need to buy?

You need a strain relief clamp

or cable gland

(images for example, not an endorsement)

Since it's NM-B, the top one. The bottom one is for round cordage.


Connecting a C-wire to a Burnham Independence Boiler I would like to install a Sensi thermostat which requires a c-wire. I am planning to run a new thermostat wire, since the old one was 18/2. I am trying to figure out the correct way to wire the c-wire for the new thermostat wire, if possible. The wiring diagram for the boiler can be found here:

http://bostonheatingsupply.com/Burnham/Burnham%20Independence%20I&O%20Manual.pdf

The set up for my boiler is on page 30:

Also, see the similar question How to connect c-wire to Burnham Series 2 boiler?. It seems in this case that 24v power was able taken from an extension plug for unused accessories, which is not applicable to this situation as far as I can tell.

Thanks for any help that you can provide!

Edit: Here are some additional pictures:

Connect C to the wire-nutted bundle of yellow wires

According to the manual for your unit, the C-wire coming off your transformer is a yellow wire (we know this because the manual has it connected to ground, among other things), that is joined with that green grounding wire and a bunch of other yellow wires, including one to the vent damper plug.  Given that the vent damper connector is likely the plug we see at the bottom of your photos, based on the wire colors going to it, we can then deduce that the junction of yellow wires in your photos is where your C wire should connect to.


Can anyone tell me what this little white box on my outlet is? Recently bought a house that's about 40 years old.  The previous owner was clearly very fond of doing the wiring himself and has left me some idiosyncrasies to work out.  One is this box in one of my bedrooms.  No idea what it is, or is supposed to do but I see extra wires coming straight out of the sheet rock on the bottom of it.  Can anyone tell me what it is?

Conveniently, it still had the UPC barcode label and you captured it quite clearly in the picture.

A search at upcdatabase.com shows that it is:

Description     Brinks Home Security System AC Power Adaptor
Size/Weight     5x3x3, 12 ounces
Issuing Country United States

A Google Search for that UPC brings up a number of hits, including on at Parts Express that shows the following specs:

Universal UB1640W 16.5 VAC 40 VA Plug-In Wall Transformer

AC Output Voltage   16.5 V
Current Capacity    2400 mA
Center/Tip Polarity AC Plug
Input Voltage       110~120 VAC

So, it appears to be a low voltage 16.5 VAC transformer that is (or at least was) a part of a home security system. Looks like the screw on top is meant to screw into the outlet for semi-permanent installation.

Of course, it's possible that it was re-purposed for something else like low voltage lighting, a doorbell, or who knows what it may be used for.


Anchoring floating deck and pergola I want to build a floating deck with a pergola but I don't want to set posts in concrete.
My yard is mostly shale with about 5 inches of actual topsoil, if that.
My question is, could I put treated 4x4 or 6x6s on the ground and anchor them with rebar, going straight through and into the shale? Or would that be too weak to hold it? So posts on the ground, held down with rebar, and then the vertical posts attached to the horizontal ones.
The highest winds we get in my area would be around 50mph, so I'm trying to figure out if the weight of the deck and pergola, plus the rebar anchors, would be safe enough.

I suppose you could do what you're describing; but, my years of building deck and fence in college tells me it's a bad idea.
Even with rock and shale (and no topsoil) wood resting on the ground picks up water, which accelerates rot, even if the wood is treated.  Also, nearly all deck framing assumes strong anchor points, so a wooden base (enforced or not) would have more lateral movement than most anchoring systems.
If you don't like posts in concrete (in my area there's enough water that these are problematic) I'd recommend looking at piers to replace the posts.  These are concrete cylinders that the entire deck framing rests upon.

If you get 50 MPH winds, then a gust would easily be a very temporary 70 MPH.  Even with low winds of half of that, I can't imaging rebar directly in dirt having enough surface area contact with the surronding earth the hold back an 8 foot lever being pushed on it's top end with 50 MPH winds.
Put the posts at least 6" below the frost line, and minimally two feet deep.  The cost of the wood that will go into the deck should be enough of an incentive to do the deck's foundation right.


Why is the water pressure so high from my overhead water tank? We have recently rented a house and it has normal taps fitte, and a normal
overhead water tank, but the water pressure is very high. The water comes out
with so much pressure, that if I am trying to rinse anything it makes
water spray everywhere. What could be the reason?

Its a normal plastic 500 lt overhead tank, and it doesn't have a cap to close its top.  It is not sealed and pressurized. There are no pressure regulators, and there is no water heater in the system. It's just a fill and use kind of tank.

For water flow, a 1.5 in. pipe is fitted to its bottom. There is a check valve, and its turned full open. The tank is fitted on the 2nd floor (25ft above ground level). We fill the tank with bore \ well water with the help of an electric pump. When we open any tap, water pressure is very high.

What could be the reason?

You may need an aerator.  If it needs replacing, then the water may spatter a lot.  The aerator is the piece that screws into the end of the spigot.  It limits the flow of water to between 1.5 and 2.5 gallons per minute and entrains air into the water stream to prevent splashing.  From what you describe, it may even be missing.  You can pick one up at any hardware store.


How do I install a cabinet door underneath a breakfast bar? I have a cabinetry-based question that I hope I can get some guidance.

The girlfriend's condo has a U-shaped kitchen.  One part of the U has a built-in breakfast bar.  I’m looking to install a cabinet door underneath the bar that will allow a second access to one of the kitchen cabinets (the cabinet that is in the corner of the U).  Has anyone done this?  Does this require one be a pro contractor or can someone that’s reasonably good with tools pull this off?

(Not that I think it would make a difference, but the reason why we’re wanting to do this is because the cabinet in question is long and skinny and it’s hard to reach stuff that has gotten pushed into the depths of the cabinet).

I think I get the picture without one :) I've seen this many times. I'm assuming the wall under the bar you want to cut into is a typical wood framed, wallboard sheathed stub wall. If not, ignore this answer.

You first need to cut out the outer layer of wallboard. If done carefully, no additional finishing will be required, though it may be easier to not be careful and just refinish. It would depend on how easily you think you can match the existing finish. Things will be easier if you plan the opening to fit between two studs, but the opening will possibly be rather small and possibly not in the ideal location. To do things for an ideal size and location, you will likely need to cut out a stud and frame in horizontal 2x4 plates at the top and bottom.

If you're refinishing, remove wallboard from floor to bar top underside and frame the opening properly so the horizontal plates support the new wallboard edges. If you do not want to refinish, place the plates below and above the wall board edges, leaving the wallboard edges unsupported and the plates exposed, they will be mostly covered in the end.

Cut out the wallboard of the opposite surface that is the back wall of the corner cabinet. This time all the edges can be supported. Now you have full access to the depths of that cabinet, but no door. The door can be anything, what I've usually seen is a cabinet face frame applied to the surface of the wallboard, which will cover the exposed horizontal plates. Then a standard cabinet door is attached to the face frame.

If you have decent woodworking skills, you could build the face frame and order the door from a cabinet supply. If not, you could order a plain face frame to match the cabinet door.

It's also possible to case the opening and install a hollow core door, sort of like a little closet. You'd need wide casing to cover the exposed plates. A simple panel door made of MDF could be fabricated and painted. You could just hang some fabric drapes over the opening. The possibilities are only limited by your creativity!


Garage door opens only partially in hot weather My Craftsman garage door opened works fine in cool weather  or early in the morning. When the weather is hot, it opens partially, from 1/8 of the way to 7/8 of the way. Pressing the remote closes it, and pressing again it opens it, but less than the first time. Doing that again it opens even less.

Any suggestions?

Step one - when it's hot and acting up, close the door, disconnect
the opener, and open it manually. If thermal expansion is making the
door bind, you need to address the basic mechanical issues of the
door mechanism BEFORE you start cranking up the door opener. Clean, lubricate, adjust, or call a garage door mechanic, as apprpriate to the issues and your skills.
Then go though the complete adjustment procedure for your opener, including the safety tests that are supposed to be run every 6 months or so (stops when beam broken, stops and reverses when hitting a 2x4 laid flat on the floor, closes and stops correctly when nothing is in the way, opens correctly. At this point you may adjust the force if the mechanics are correct.
If you've done those things and it still acts up when hot, or if your adjustment procedure doesn't seem to work as it should if you do it when it's hot, you may have a problem (evidently of a thermal nature, or aggravated by heat) in the logic board of the opener. I had some very puzzling behavior from an opener once that appeared to have been caused by a nearby lighting strike scrambling it's little brains, and making it into a potential killer (it was trying to drive the garage door through the floor when it closed.)


Water meter leak indicator moves once in a while What is driving me a bit not sure recently is that the water meter leak indicator sometimes can move a bit over a long period (say an hour or a few hours). My water meter is a Procoder meter same as below.
I guess the smallest interval for the red leak indicator is 0.0001 cf which is about 0.1 oz or 2.8ml. Not sure if my reading is correct.
The red indicator sometimes can move a few intervals (~10ml) over a period of a few hours. But sometimes it just makes no movement over a period of a few hours. I wonder whether this is acceptable?
I cannot figure out what is happening. I do have a 40 gallon water heater and a water expansion tank (2.1 gallon). I sometimes wonder whether it can be just temperature fluctuation which causes either the water or the air in the expansion tank to contract/expand. Any suggestions?
Btw, I am doing this because the house had some pipe work and garden sprinkler lines done recently, and I am checking for possible leaks.

Max, with that small of a “leak” I would not worry about it but I may try an experiment where you turn your water heater off for several hours and see if it is any different this test may be more accurate if some hot water was used after the water heater was turned off so the cooling down or cycling of the water heater might be eliminated as the cause but .0001 cult is a very small amount of water. And probably not worry about as it is not a consistent leak and may be due to water heater temp cycling.


Concrete column splice - weld or surround with 6mm? I have a concrete column using 16mm rebars. The column needs to be extended (and of course the rebars) for the 2nd storey of the house that is being built. Should the splice be welded or surrounding the splice with 6mm spirally will be fine?

Please do not suggest me to contact my contractor or engineer since the reason I posted this question here is because that is not possible in my case.

I only need some ideas.

Thanks!

Historically rebar has had high carbon so so very likely to crack if welded.  Modern rebar is lower carbon but is not intended to be welded. Depending on the composition of the rebar you have a fair chance of no cracks in the weld zone. I would stay with the traditional wire joint.


Can I use normal metal electrical box for outdoor low voltage installation? Installing a few PoE IP camera under the eave, I am trying to put a electric box to contain the network cable connection and to prevent vandalism.

As I have a few normal interior metal boxes lying around, would those be considered ok to install in a damp location for low voltage device? (metal box like this: https://www.lowes.com/pd/Raco-2-Gang-Gray-Metal-Interior-New-Work-Standard-Square-Celing-Wall-Electrical-Box/3129657 )

These electric box is used only for vandalize prevention.. I am not relying on that for the weather proofing. The ethernet cable has it's own water tight connector and I will be painting these boxes just to make it rust slower.

My concern is would that be something against the code? Really not sure about the low voltage related code. Anyone knows about it?

Only code problem is the UL listing. I am pretty sure those are indoor rated only and not even for damp locations.

Also, unless protected from rain, it would be considered a wet location, not damp.


Understanding results of an energy audit We had an energy audit done a couple of years ago on our 20 year old home.  Basically, they hooked up a blower to the front door, and tested the amount of air leakage.

The written report suggested a number of improvements, most of which we did:  new windows, doors, sealing attic hatches, etc.  The total spent was around $15k.

Because there's a local government plan to cover some of the expenses, we had a follow up audit done.

The overall score from the follow up was exactly the same.  This really baffles me, because I know in a couple of places (pre-repair) I could feel a breeze coming in, and the candle test showed it.

Will I actually get any savings from my new, expensive, energy-star compliant doors & windows?

Plugging air leaks in you home is a bit like sticking fingers into a leaking dyke. Plug one hole and another one breaks through. Generally, the situation should have improved with new windows and doors (if installed properly).

The technician doing the post-audit should have identified where the air was coming from so you could fix that too.

One possibility is that a fire place flue or external fresh air duct to your funrnace was open during the blower test. This would have let a huge amount of air in. Other things to look for are stuck flapper valves in bathroom and kitchen vents.

Another place to check and seal would be around the sill plate. Often there are a number of small air leaks here. Individually they are not large but in sum they can amount to a significant air leak.


Do braided stainless steel hoses with surface corrosion require replacement? I'd be grateful if someone would resolve some conflicting advice I've been given on this topic.

Some argue that the braiding does not contribute to the pressure rating of these hoses, and that surface corrosion does not indicate urgent replacement.

On the other hand, online sources such as this (in addition to this study) imply the contrary, that corrosion is among the causes of braided hose failure.

What would you say is correct? Would extensive corrosion require urgent replacement?

It really depends on the type of corrosion, some may be more surface finish failure and the hose can last for many years if not a decade. I have seen rusty lines that have some of the strands breaking and the line was not leaking not yet, I would suggest once the outer braid starts failing it is time to replace the line.  the urgency would be based on several factors like is the line disturbed or bumped my wife has a buck she stores under the sink that bumps the line in that case it may need to be replaced sooner than one that is never touched.  The pressure is also a factor, if you have less than 60 psi I would not be as concerned compared to a home with 90 psi. The last is personal opinion, some want to replace for any reason others may wait for a drip and each opinion is probably based on past experience and disposable income.


How to split a circuit I have a one floor house with semi finished basement. On the main floor the Living room, Bath, 2 Bedrooms, garage and Microwave outlets are on 1 circuit. If I go to skinny breakers I have room to run a couple of lines from the breaker box and could get them to a couple of outlets on the main floor without poking too many holes. The breaker box will accept the skinny breakers. My question is can I pick 2 random outlets to run the new lines to and split the circuit, if effect turning it into 3 circuits? If I can, how do I go about it? Steps.

I am handy but have not done much electric work. I have switched pull-chain lights, installed outlets, installed some outside light fixtures. But that is about it. I have not screwed with the breaker box before.

I'm in MN. The breaker box is a standard 24 slot GE 100 Amp box. While I'm sure there is a way to upload photos, I don't see any link on this page to do so. – Pat

Yeah, that's fine.  Plan your breakpoint carefully based on the loads you expect.

For instance I like to break circuits mid-room, so BR1 has half of circuit 1 and half of circuit 2, and BR2 has half of circuit 2 and half of circuit 3 etc.  That way if you make one the computer room, and need to plug in both a gaming PC and laser printer, you can put some on each circuit.

Make darn sure you're not making a loop.  Check that by sticking a load in every outlet, and go through each breaker, turning it off while the others are on.  Make sure every outlet turns off with exactly one breaker.


Does voltage in my PC's case indicate a circuit grounding problem? Today I was on my computer, and I wanted to plug in an external battery powered speaker to my PC's front audio jack using an AUX cable.

I noticed as soon as I plugged it in the familiar burning smell when something like a capacitor or resistor burns out, so I immediately unplugged everything and noticed that the AUX cable was very hot. After I had a poke around inside my computer, I couldn't really see anything that looked damaged. After I had a go turning it on again, the audio still worked (through the rear jack) so it looks like it didn't blow the sound part of my motherboard.

However, after doing some more investigating, I noticed I could feel a slight tingle on my computer case when touching the case and what I think is a grounded point in my house (touching the shielding of a coax cable coming out of my wall). After making sure my PC was plugged into a grounded socket, I still felt this sensation. Even weirder, when I unplugged the case, I still felt the sensation when touching the grounded point.

Could this mean there is something wrong with my ground and it always has some potential running through it?

I concur with your theory that the case is under power.  This may be due to a ground fault in the PC's power supply.  It could also be some other appliance raising ground due to its ground fault combining with a gap in the grounding system.

It's possible to have "islanded grounds" where a bunch of equipment grounds connect to each other, but do not connect to the actual earth. In an islanded-ground situation, you have the lowest common denominator; a ground fault on any of them lights up all of them.

The Equipment Safety Grounding System (outlet to panel), combined with the Grounding Electrode System (panel to ground rods), should be handling that properly.  I'd say it's time to give both systems a heavy inspection with a 10 foot pole... sorry, I mean with a fine-tooth comb.

If your grounding electrode system is faulty, that's where the 10-foot poles come in.


Can you buy an inexpensive rectifier/dc power source for cheap flickering LED Christmas lights? OK, I bit on Home Depot's door buster LED christmas lights... 150 LED lights for under $5 each. How could I resist? (Answer: By remembering that cheap LEDs flicker, AND that I'm sensitive to it. )

https://www.instyleled.co.uk/what-causes-led-flicker-and-how-can-i-stop-it-happening/

Seeing as how they were door-busters, they are also non-returnable. I'd like to figure out how to make them work. I've done some research, which has shown that it's possible to create a dc rectifier/transformer/ that will make the flickering stop.

https://www.youtube.com/watch?v=mqRd3q7k9OU

Now, I think I can do all of that (I love soldering that gives you that much room to screw up. BUT, I'd rather just pay $5 for a professional version that absolutely positively won't overheat and burn down my house. I can NOT find anything that's not built for uses like under-cabinet lighting or dimmers, and which have specific connectors for specific manufacturers. Does anyone know if anyone sells something like this, or if there are kits that are a little LESS DIY in nature? Thanks!

No-one will sell a commercial product like that.  It's dangerous.

DC is nasty business. Seriously, go to mouser and pick any random power relay.  Look at its specs for AC, and then look at its specs for DC.  Whoa!

DC is de-rated by a large factor because when a DC arc strikes, it doesn't self-extinguish because the voltage never goes to zero.  An arc, once struck, doesn't feel pity or remorse or fear and it absolutely will not stop until it's burned up so much conductor it can no longer bridge the gap, and if that sets your house on fire, too bad.  If you've seen old "snap switches" which have a considerable action to them, they are preloading and releasing a "snap" action which creates a large gap when the contact breaks. Larger switches and contactors have designed-in "blowouts" which bend the arc into an arc-chute.  The point is, interrupting DC takes a lot more design and engineering than interrupting AC. And a short is a much bigger deal.

Now when you rectify AC into DC, you get a bouncing-ball waveform.

Supposedly that should self-extinguish same as full-wave AC, but capacitance will prevent it from getting all the way to zero.  If you add a smoothing capacitor, then it has no chance to extinguish. You wouldn't want to do that anyway, because that would raise the average (RMS) voltage, which could overcurrent the LEDs.  LEDs are non-linear, so a small voltage increase makes a big current increase.  The curves are in LED spec sheets.

Of course if you could constant-current regulate each LED chain, it's perfectly wired for that.


What methods can I use to remove exterior paint from brick? I just purchased a historical house that was painted an ugly peach color. I bought some marine grade paint stripper that I was going to use little by little to strip the whole exterior by hand.  This doesn't seem time or cost effective.  I want to know what options are available to me to remove this paint without damaging the brick and mortar. Whether it be something I do, or a service.

I found this How can I remove paint from an indoor brick wall?, which mentions sand blasting and dry ice blasting. Is there anything else I can/should consider?

This all depends on how long the paint has been on the house and what kind of shape it's in.  Because brick is a porous material paint adheres very well to it.  I think your first step would be going to the local paint store and rent a power-washer.  A gas powered power-washer.  You are going to need as much psi as possible (at least 3000+) with a pin-hole revolving tip. This will blast away any paint that is loose on the brick.

This should be less damaging to the brick and mortar than sand blasting.

Depending on how successful this was in removing paint dictates your next steps, if most of the paint is gone, then maybe just a wire brush and some paint remover will get the job done.  If you've power-washed your whole house and it is still covered in paint, then I would call a contractor and get quotes.


Distance between countertop power outlet and gas range Is there a minimum distance between a gas range and a power outlet? My logic for concern is that a power cord close to a gas range can catch on the flames from the range. E.g. is 9" diagonal from the range okay, 6" lateral distance.
Please note this is not the outlet to power the range but just a countertop receptacle.

Code doesn’t restrict the location of a range receptacle. They are normally behind the range location most are below the counter height so the receptacle is not visible when the range is in place. The builder has no idea what range may be used in most cases.
Added to be more specific; the location of countertop receptacles is not restricted other than there must be one within 2’ of counter space or 4’ between. The receptacle can be mounted adjacent to a stove cut out and or adjacent to a sink location but there are no restrictions the same as the location of the receptacle behind the stove if one is installed.


How can I join two solid surface vanity tops for a seamless appearance? I purchased two Swanstone solid surface vanity tops for my double-bowl sink.  I trimmed them to site side-by-side and planned to use white silicone caulk between them to fill any very small gaps.  They looked fine going in but the caulk sunk some after it dried and so I am thinking I need to take one out and fill the gap with something else that will have the following properties:

Non-porouos
Easy to clean
Same or similar color as my tops
Will bond to solid surface

I have considered epoxy of some sort, but I'd like to know if there is anything that is commonly used to this effect.  I have seen granite tops lined up with little noticeable seam so I think it should be possible.  Of course, I should have picked a darker color to hide the seam better but... live and learn I guess.

UPDATE:
I received a response from Swanstone:

  Hi, Corian can be chemically bonded but Swanstone cannot. We do a
  mechanical  bond and then fill seams with an acrylic glue. These
  products are only available to certified swanstone fabricators. If you
  would like information on that, give me your location and I can tell
  you who to get in touch with.

I already have a mechanical fastening system in place, not pictured are three 1/4"x20 bolts in the front, back, and middle of the sink spanning the vertical supports of the two halves, which happen to butt against each other.

Addendum: Good info in general re: swanstone fabrication: http://www.jlconline.com/countertops/working-with-thin-solid-surfacing_1.aspx

Update: I followed Jack's advice and used glacier white SeamIt brand solid surface adhesive (2 part epoxy).  The results are not bad, the only downside is that the adhesive itself has a different sheen than the swanstone so I think I'll try to rough it up later to cut down on reflections off of the adhesive line.  The finished product is pictured below.

The makers of those tops will have the seam adhesive to join the tops permanently.
If they are anything like Corian by Dupont, they want to protect their warranty. You may need to do some convincing to an installer to sell you the adhesive you need. It can be done, I have done it before. It takes a router or a belt sander to get the joint down flush after the glue squeezes out.

More later if you go that route.

12-9-13 addendum

The bond is really strong, but it is always best to insure the joint is stable on both sides. This can be done with silicone under both halves. While silicone is still fresh, position your halves and use shims from the underside if needed. From the looks of it you may not have the luxury of getting a clamp block at the back edge but you may at the front. Have everything ready, and clamp the front and shim the back like you are ready to glue. Get it right at this point after this step there is no turning back. Use a straight edge of some sort to insure surface are flat and true. Remove all clamps that block access to the joint. apply your bonding cement and reset the clamps. The stick(s) I have referred to are small hardwood scraps, maybe 1/2" square to 3/4" square and 4 to 6 inches long. When this is placed on the glue joint it will spread the glue a little, but it will sand out with the rest of the joint.

After all this is said, any of this is for worst case scenario. If the joints line up perfectly as it sets on the cabinet, which it looks real good in the picture you offer, all you need is to apply the glue and let it set which will only take minutes to set, and hour to finish.


Can I legally run wiring through a window or its frame? I am planning on hooking up a hot tub in our in backyard and we need to run a wire from the breaker panel to the tub. Although we could run the wire through the concrete, there is an unused basement window and it would be easier to run the wire through the window or its frame.

I imagine other people wanting a hot tub may also have a similar situation. I've attached a picture of both sides of the window for reference. I've also attached a picture of another location in the house where someone has done exactly as described.

Is it okay, as for as the ESA (Electrical Safety Authority) in Ontario (Canada) goes, to run the electrical wire for the hot tub through this window?

Thanks so much.

First, does the window open, and is it required by fire codes for emergency egress?

If so, you could remove the window and install a shorter or narrower window, that still meets code, and then use the margin to pass through your utilities.  I would use fairly tough metal conduit for electrical to make it resistant to damage.

I already see a wood margin that might suffice.

Otherwise you'd want to permanently remove the window from service as a window, by doing a surface treatment on both sides that renders it not a window.   Either remove the window entirely or panel it over on both sides so it is entirely buried, remove a pane, put the service through, and fill the voids with insulation.

I hate to remove a classic window like that made of solid material and well installed, so I would go for the remove-a-pane option.


Recirculation pump seems to be working, yet no detectable heat on return pipe Our two-story-on-a-slab house has uninsulated copper pipes, including a recirculation return pipe to a tee on the water heater drain. In past years, the recirculation seemed to give us hot water fairly well (though at an energy cost), but less well of late.
We recently changed out the hot water heater, and replumbed the recirculation system because of physical differences. We found that the return check valve was stuck open by calcium deposits, and the aquastat was not even connected. We have added a timer for the recirculation. The existing pump is a Grundfos UP 15-42 SF (59896171). AC power to the pump measures 75 watts and 75 VA.
A water pressure gauge on a tee at the water heater drain measures a rise of 5 psi when the pump runs, so seems to say that the pump works.
But, we find that even after letting the pump run for an hour, there is no detectable heat on the return pipe, and no hot water available at faucets. Where do we start in getting this to work properly?

P.S. We also have a Chilipepper demand pump in the master bedroom bath, farthest from the water heater, and it works great (crossover hot to cold until temp rises); but wife objects to the noise, and would like the timed recirc to work.

old photo - http://smg.photobucket.com/user/acellier/media/Recirculation/2014%2010%2017%20old%20water%20heater.jpg.html
new photo - http://smg.photobucket.com/user/acellier/media/Recirculation/2015%2003%2011%20installation.jpg.html

A thought - could the heater possibly have a check valve on the drain???

D'oh - Problem solved. Heater drain valve was not opened sufficiently, due to unfamiliarity with the new-style plastic collar-operated drain valve. The key clue was the rise in indicated pressure, which showed that there was impedance into the tank. With the valve correctly opened, there is no rise.


Installing/fixing ceiling drywall when trusses are uneven? My house is an "L" shape where the short leg of the "L" is the garage.  Above the garage ceiling, the trusses transition from one orientation 90 degrees to another orientation.  The different orientations of trusses are different heights above the floor.

This means one-third of the ceiling has the bottom edge of the trusses 1/2-inch lower than the other two-thirds.

When the ceiling drywall was originally installed, the drywall was butted up at this uneven transition and caulked.  This joint has failed over time, and then wind blows through the joint (when the garage door is open) making the problem even worse.

What is the proper way to fix this situation?

You'll have a header running across the 90° transition in the framing direction, so this shouldn't be that difficult to fix.  I'd remove the drywall from the last stud bay (shaded below)...

...and attach blocking to the header that will catch the sheetrock. Since you're getting air ingress there, I'd take the opportunity to insulate while you have it open. I'd also use fiberglass tape instead of paper along this joint when you put the drywall back up - I've found that it tends to hold up better along seams like this.


External Air Conditioner Condenser Capacitor replacement I have a couple of questions about testing and replacing the capacitor on my home heat pump external condenser unit.
1. How can I reliably  test the capacitor (what tools do I need?)
2. What safety precautions do I need to take when handling the capacitor (aside from the obvious task of shutting off power to the interior blower and external units). This is a capacitor and it stores electrical current. I'm assuming I need to wait a period of time after I've killed power to the unit before handling it.

Changing a cap is easy you have the basic idea. First pull the fuses or disconnect the power to the unit the disconnect should be close to the outside unit. Next if your cap has 3 connections use a screwdriver to short the common or c post to the fan then common to herm , if 2 post just short them together it only takes a second to fully discharge a capacitor. Make sure to note the wire colors connecting to the posts. To check the cap if your meter doesn’t have a capacitance meter built in use the ohm meter (no wires connected to the cap put in ohms and put the meter on the cap you are looking for a slowly raising value if it shows totally shorted the cap is bad if there is no charging or slowly increasing resistance try swapping the leads and now it should be discharging or the valve dropping, this is a crude test but it will point out a bad cap in most cases. Other things to look at, of the cap is bulging at the top or bottom or both even if it reads good it’s time to change it I just had a 5/55 fail to start a unit this week measured the cap it showed good but then I noticed the top was really bulged, I replaced the cap 15$ if you can wait and get it on line or 2x from a local parts house. Make sure the voltage is the same or higher on the new cap, you want the same capacitor values but if you can not find the correct one one with a value within 10% will usually work fine. The 5/55 on the cap I just changed is 5 micro fared and 55 micro fared and the voltage was listed as 400v  that is a common size so the parts house had it. I installed the new cap making sure the strap was tight and not over the size info (if the name and size can get worn off I write them on the case or inside the unit so the next time it is available). Depending in the age of the unit I might change out the contactor a bad starting cap can cause damage to the contactor, so if it’s an old unit or a really cheap contactor it’s only another 20$ to do this now and will prevent call backs. Once the covers are back in place it’s ready to see if this did the trick.

I am mentioning this next part because many times I think a low charge has caused harder starts wiping the cap out. I have found more than 50% of the time when changing a cap the super heat and sub cooling values are off (loss of some of the charge) I will add as needed to bring the system back up to the proper temperature/pressures and double check for leaks but almost never find them. The majority of the time it takes 2-6 lbs in residential systems from my experience if the system takes more than this I can usually find a leak or the system is very old and has not been serviced since install.

So make sure with the power off to short the terminals of the cap’s, if any bulging they need to be replaced, it is much easier to toss a bulged cap than clean up several hundred feet of foil/plastic & oil if the cap blows apart.

Hope that helps and good luck