Type of valve to use on PVC misting system I am making a misting system for my back patio that consists of 1/2" pvc and connectors that have the misting nozzle drilled. I am putting a nozzle every 2 feet and going about 30 feet down my patio cover

I plan on using a sprinkler water supply hard out that is currently capped off. Next to my other sprinkler valves and running 3/4" PVC to the patio and then convert to 1/2"after I run vertically about 8ft with the 3/4" pvc.  The distance from patio to valve is about 14ft horizontally.

At the end of the 1/2" run, I am just going to cap the pvc.

My question is, what kind of valve should I use since this is a long run of pvc and it has height, meaning lots of backflow/pressure.  I was thinking of just using a common sprinkler anti-siphon valve, but would the entire contents of the pvc exit the valve when I turn it off?  My pool top off uses a gate valve with no backflow and it has a little water hammer effect on start and stop, but works fine. The exit is below the valve though.

I was hoping to use a sprinkler valve with a solenoid so I could eventually hook it up to my sprinkler controller and digitally control the misters.  Eventually I would get the IP controller and be able to do it from my phone, but I want to make sure I handle all that water above the valve correctly.

Any assistance is appreciated.

I don't think you need to be concerned with using an anti-siphon device, as the potential for contamination is minimal (compared to water making contact with the soil).

If you want to automate then use an in-line solenoid controlled valve without anti-siphon, then you don't have to worry about the remaining water standing in the pipe length from running back out of it:


Boxing out floor joists when using 11-7/8 I-Joists? Back in the day with dimensional lumber joists, it was common to box out an area for something like a tub drain that could not be moved due to floor plan layout.  I remember seeing 2x8 or 2x10's doubled up on each side that a joist-box was needed. Then normally the floor joist designated for running where the drain box was made would stop short and hang on a perpendicular short joist spanning to both sides of the doubled joists.

However, what is the most economical way to do that with today's modern I-Joists? It would be rather expensive to run double I-Joists on each side, and it would seem hard to fit something like an LVL block in place between two joists because there is not an engineered LVL hanger I can find and I don't think the two side I-Joists would be rated to carry that end load especially if it's something like a tub full of water on this span.

Since I-Joists are an engineered system, it's vitally important to follow the specific instructions (including the "you can't do that" instructions) of your specific manufacturer for the specific product you have, as they are not all the same. Mine came with at least 4-5 double-sided pages of detailed instructions covering common issues.

I would strongly question the wisdom of following a floor plan layout destined for I-joists which parked a tub drain going through where an I-joist should be. That's poor planning for the construction method. If you are in the "as yet unbuilt" stage (which it sounds like) then redesigning the joist placement or tub placement so that they do not conflict would be the best approach. Generically, a single extra joist and different joist spacing (such as 19.2 inches rather than 24, or 12 rather than 16) in the immediate area should be an adequate solution that does not involve the compromises of mid-span support. Alternatively, a tub with a drain in a different location might solve it, without moving the tub itself.


Is it considered safe to connect ground to neutral with GFCI outlets? I am retired electrician. I have had contractors tell me to change ungrounded (2 prong) outlets to 3 prong and connect the ground to neutral (bootlegging). There was only 2 conductor/no ground cable going to the metal box. Grandfathered in was his answer.

Another contractor (similar...no ground to box) permitted GFCI replacement, but bootleg the ground...and no marking.

Both appear to be illegal. Is this unsafe?

Yes you can replace two prong ungrounded receptacles with GFCIs. Since you say you are a retired electrician I'll be brief. 2014 NEC Article 406.4(D)(2) will explain how to do it.

No you should never bootleg a ground. If you want to install a ground, it can be added as outlined in 2014 NEC Article 250.130(C) and Exhibit 250.47. They can guide you through it.

I am mentioning the NEC year because these articles have moved around in different editions. Good luck explaining it to contractors. Hope this helps.


How do I upgrade a conventional switch to a dimmer? I have a single pole light switch (I guess that means 1 switch controls the light?).  The top switch turns the light on, the bottom switch turns the fan on.

I bought a dimmer, that has a black screw, a gold screw, and a ground.

Coming out of my wall is:

Several white wires all tied together
Several Black wires tied together and 2 going into the existing switch.
A red wire going into the existing switch.

How do I get these all wired up? I'm fine using the pull string on the fan.  Also, what is the danger if it's hooked up incorrectly? Will it just flip the breaker or will all hell break lose.

Breaking it down:

The white wires all joined together are the "neutrals". In an AC circuit, the neutral is the "undriven" side of a circuit, which does not have a voltage potential when the circuit is disconnected. You can kind of think of it as the "return path" for current, but as the current changes directions 60 times a second in the U.S., it's not quite so simple.
The bare copper wires, or sometimes green-jacketed, are your "grounds". They are a safety mechanism that provides an easier path to ground for "rogue" electrical current (frayed wires, miswiring, etc etc) than through you, or the flammable structural members of your home.
Black and red wires are "Hot" wires; these wires carry the electrical potential needed to "drive" the electrical circuit. These wires are the ones that will kill you when the power is on, even if the circuit is disconnected. Black is the "Primary" hot wire; red is usually an "auxilliary hot" to separately control two parts of a system, such as the light and fan of a ceiling fan fixture.

To properly answer your question, we need to know if you have two actual wall switches, and are just replacing one, or if you have a single module in the wall box that has two switches on it. If it's the former, then what you have (which sounds like a simple single-pole dimmer switch) is fine to replace one of the switches. If you have a combination unit that takes all these wires and has both fan and light controls, you can still make it work but you will lose control of the fan at the wall.

It sounds like you have a single unit with two switches on it, taking up a single wallbox space, and you are replacing it with a single-pole. Here are the basic steps for this:

Turn off power to this circuit, and any other circuits that may happen to be in this wallbox, at the main breaker panel.
Remove the wallplate but don't unscrew the switch itself yet.
Test all the wires with a non-contact voltage tester (an absolutely essential safety tool for electrical work) to make sure all the wires are "cold". Repeat step 1 if the tester lights up.
Unscrew and pull out the switch. Identify where each wire is currently connected, then disconnect all wires. It will be extremely helpful if the switch is marked to identify which wire is which, but it's not critical.
Identify the "panel hot". In your situation, this should be either the wire connected to a terminal marked as "in" or "from breaker", or if the switch isn't that well-labelled, it is the black wire that does not come from the same outer insulation conduit as the red wire.

If this is difficult to determine, separate all wires and ensure that none of them are touching anything metal, then turn the power to the circuit back on at the panel. Do not touch ANY of the wires with any part of your body and don't allow ANYONE else, especially children, to come anywhere close to the exposed wires. CAREFULLY use your non-contact voltage tester to look for the black wire that carries current. Remember or mark that wire, and cut the power at the panel again.

Look at your new switch. There should be a terminal towards the top of the switch body, a terminal to the bottom of the switch body, and a terminal that screws into the metal chassis of the switch (which is usually anodized green, and is your ground). Connect the "panel hot" to the "bottom" switch body terminal. It USUALLY won't hurt anything if you connect it to the other switch body terminal, but DO NOT, under any circumstances, connect the black wire to the chassis terminal (the "ground"); that will at least cause you not to be able to turn the breaker back on, and at worst will "energize" the switch chassis including the metal wallplate screws; if you touch them you'll get shocked.
Now we need to figure out which of the other two wires goes to the light, and which goes to the fan. If the old switch gave you any clues, great. If not, trial-and-error won't hurt anything.

Pick one of these wires and screw it to the SAME terminal that you screwed the panel hot wire to. The switch will just be a convenient place to join these two wires for now; you won't have to make sure the switch is on or anything. Go turn the panel back on, and see what turns on, either the fan or the light. Turn the power back off at the panel.
If the fan turned on, you guessed right. Leave those two wires connected to that terminal on the switch, and connect the last wire to the other switch body terminal.
If the light turned on, disconnect the wire you chose from the switch terminal (leave the panel hot connected). Instead, connect the wire you didn't pick (which should go to the fan) to that terminal, and connect the wire you picked to the other switch body terminal.

If this switch is in a "wet" area (within 6 feet of a sink, tub, shower, or anywhere you could possibly imagine standing water such as your basement), you are required by code to connect a ground wire to the switch. If this is the case, or you just want to be ABSOLUTELY sure, then head to your hardware store and pick up two additional items; a length of 14AWG bare copper wire (you can also just buy a length of 2-conductor Romex wire and remove the copper element from it), and some wire nuts of the appropriate size for 14AWG wire. They make special "grounding" wire nuts that are green with a hole in the top, that create a "Y-junction" joining several wires to one wire that then connects to a device chassis. These can be useful but shouldn't be necessary. Screw the wire into the grounding terminal, cut to some appropriate length, and twist the other end around the grounding "bundle". Use the wire nut to ensure it stays put.
Wrap the entire switch body with a layer or two of electrical tape, being sure to cover all the electrical terminals on the switch. This is an extra level of insurance to prevent short-circuiting when you put everything back together.
After making sure there are no bare wires showing other than the ground wires, and being careful not to pinch any wires, put the switch back in the wallbox.
Turn the power back on at the panel. The fan should start up; it is now effectively "hard-wired" into the circuit, and you will need to use the pull-string to control it. The switch should control the light; on/off/dim should all work normally. Make sure that the dimmer does not also affect the fan; if it does, turn the panel off, go back to step 7 and swap the wire you identified as going to the fan to the other terminal; it somehow ended up on the opposite side of the switch as the panel hot and is being controlled by the switch.
Once everything's working to your satisfaction, put the wallplate back on and enjoy.


How do I keep this old shower pan water tight I have my shower room down to the studs.
It has an old terrazzo shower pan which I hope to reuse. It had an inch high metal (lead?) edging around it. It was fairly decayed so most of it has broken off or been removed.

I have Wonderboard lite and Redguard ready to go up, but I'm not sure if I need something to further waterproof the section between the shower pan and the backerboard? I had a drywall guy in and he mentions that there is usually a rubber strip on new shower pans that prevents water ingress.

Is there something I should do before putting on the wonderboard / tile?

Nothing but caulk (100% Silicone), is the hands-down best I've found.

The Wonderboard would sit (actually stand-on and rest-on before screwing down) on the Terrazzo's top and back lip in a squished-out caulking bed for drain backup flood waterproofing.

You really don't want any firmer type of gap-creating "gasket". Then, your Redguard, Thinset & Tile overlap that seam. They are all that really makes everything actually waterproof.

You can then chose to either rest your tile down to & on the inner and lower secondary Terrazzo lip above the pan floor or you can raise it slightly to grout a larger joint. Neither is any different in waterproofing, but not grouting means no ugly possible breakaway crack later.


Did I harm the integrity of my house trying to run a wire? I wanted to run a CAT6 cable simply from a first floor room to the second floor room directly above it. I drilled through the bottom plate in the wall on the 2nd floor as shown. I first used a 1/2 in bit, but it was not long enough so I bought a 5/16 one that was 1 ft. Unfortunately I messed up with the first hole and had to stop because due to a slight angle it started poking through the dry wall on the other side (just open air into the house entryway). Seems that the 1 ft one was not long enough either surprisingly because there is still not a thru hole. I'm most worried about whether this is now unsafe, but if not, what is the problem here? Do I need an even longer bit?
UPDATE:
I took out the drywall in the room directly below this, and found a large wooden beam spanning that wall, from at least ceiling level to 1ft down. That wall also has a large opening for a folding door. I fear I really shouldn’t have made those holes— maybe that huge beam is there to compensate for the opening, i.e. lack of studs? What do you think? On the bright side, I got the CAT6 cable out through an exterior wall and ran it up the brick and it looks and works quite good!
Purple is where I know for sure there is wood, green star is directly below the drill holes:

First - you have done nothing that will harm your house other than give a few bugs a raceway, but this is the 50th raceway, not the 1st.
Second - you will have to open it up from below to see what is there.   You went through bottom plate and subfloor.   You probably (almost definitely not) don't need a longer bit.


Can GFI breakers or GFI outlets allow grounded outlets to be used? I have a 1963 house in Texas with Square D breakers and mostly duplex plugs.  All metal outlet boxes. However, there are 8 romex style cables (12-2 with ground) tied to the breakers in the service panel. The ground wires have green insulation and I think there are 8 plugs that have the ground attached to the metal outlet box. Many more outlet plugs are duplex and no grounding (even tested it). I see no conduit or metal cable sheathing anywhere. Is it true I can either 1. replace all breakers with GFI's and then change all plugs to grounded outlets? or 2. Replace just the first outlet coming from the service panel for each circuit with a GFI outlet and then change the rest of the plugs to grounded outlets?  Not much chance to run just a ground wire to each receptacle.
Really want to modernize and end up with legal protected outlets for 110 circuits.

Yes, you can protect those outlets with a single GFCI per circuit and put three-prong outlets in the boxes. There will still be no ground wire and no actual grounding in those outlets.

(You cannot connect the ground terminal to the neutral; this is a code violation, and dangerous since it puts current on the ground wire, specifically causing the ground wire to act as a live conductor if there's a fault in the neutral, and will energize the screws on your face plates, energize the housings of grounded power tools and grounded appliances like toasters, etc.)

Technically, all un-grounded outlets that are protected with GFCI are supposed to be labeled "GFCI Protected/No Equipment Ground" (GFCI outlets will usually come with a little sheet of adhesive labels in the box for this purpose).

I agree generally with the comment about using GFCI breakers, although you certainly can replace the first outlet on a circuit with GFCI and protect everything "downstream" by connecting the downstream part of the circuit to the LOAD terminals on the GFCI.

Square D 20A GFCI breakers cost about $35 each. GFCI receptacles probably cost half that.

GFCI and grounding are two different concepts. GFCI's will protect people against electrocution, but they do not provide grounding, so they don't provide any protection to equipment that really requires grounding.

For some appliances this probably isn't an issue as the GFCI will provide protection against electrocution and there aren't other noticeable effects that matter to you.

For more sensitive electronics, like computers, TV's, radio and sound systems, running without a grounding conductor can subject your equipment to irritating (at best) effects like ground loop interference (which might sound like a background hum through speakers, for instance) and may or may not cause problems or damage to the equipment itself or even danger to your structure. If you have satellite equipment, there are explicit code requirements for grounding. Also, connecting surge protectors to a circuit without a ground probably won't allow the surge protector to be fully effective.

Inside the GFCI there are identical little inductive coils around the hot and the neutral conductors, and the GFCI circuitry trips if it detects any imbalance in the current between the hot and neutral. The neutral carries the same amount of current as the "hot" in a circuit with a load on it. If the neutral is not carrying the same amount of current, that means current is leaking to ground (a ground fault) through some other path, which might be a person. But the GFCI doesn't have anything to do with grounding the circuit.


Where to connect c wire at furnace for Honeywell Wi-FI thermostat We are installing a new honeywell wifi thermostat have an extra blue wire in our bundle.  We aren't sure where to connect the blue wire on the furnace board.

Click for larger view

First off, the green wire should connect to the G terminal on the thermostat. It's connected to the G terminal in the furnace, and so should also go to the G terminal on the thermostat.

At the thermostat, the extra blue wire should connect to the C terminal.  Depending on the furnace (read the documentation, and analyze the schematic to be sure), you should be able to connect the other end of the blue wire to either of the C terminals in the furnace.


Hot water tank cold water is always flowing My hot water tank cold water is always flowing and it's losing water out of the temperature valve relief tube on the cold water intake side (see attached photos). I just noticed this, but it could have been going on for weeks. The tank natural gas and is 10 years old and I've never tested the TP valve until recently. I've never pulled the TP valve out to check it. I've tested the thermostat and the burner is firing fine. We have no problems with the hot water in the house. The house water pressure is sitting at around 60psi

Home Depot guy said that the pressure in the city has gone up due to check valves being installed, however I'm not so sure. He said to install an expansion tank on the cold water intake side, however, I'd like to understand what the problem is better before doing this. Another potential clue is that there was a broken water main at a house down the street, however, I don't think that this is contributing to the problem as our house pressure is 60 psi.

Is this pressure, temperature, tank related, or perhaps a failed temperature control valve problem (on the cold water intake)?

What should I do to better diagnose this problem? Should I replace the temperature control valve on the cold water intake? Install a expansion tank? If so where would I install the expansion tank on my cold water side?

edit: That "temperature control valve" is actually a thermal expansion valve.

From the website: https://www.mmcontrol.com/apollovalves/plumbing.php

  Apollo® 78RV Series Combination Water Heater Isolation Valve/ IAPMO
  approved Thermal Expansion Relief Device. This combination water
  heater shutoff and thermal expansion relief valve is an ideal
  alternative to expansion tanks in residential plumbing systems.

Update 2:  I have run the cold and hot water tests for both at 5 minutes each and neither have stopped the flow of water out of the thermal relief valve. When I closed the valve completely, the water still flowed, however it turned to hot water after around 3-4 minutes. Does this mean I have too much pressure inside the tank? Replace valve? Install expansion tank? Replace water heater? Call in the pros? :) Many thanks again all.

Please see attached photos for details.

Thanks
E

I'd try replacing the relief value that is screwed into the shut off valve to see if it solves the water flow issue. Sometimes once they are activated, they don't like to stop for varous reasons.

As for the expansion tank, it should be installed before the water heater. They are normally installed near where the water comes into the building.


What valve should I use for water control flow after upgrading to thermostatic valve? I had leaking valve assembly for a beauty salon's hair washing station. It had a handle that allowed to independently control temperature and pressure. It looked like this:

And, to save water and for convenience, I just bought thermostatic valve that looks like this:

And the shower head with hose that I may or may not reuse looks like this:

Since, thermostatic valve is not designed to control water flow, then I need another valve that would do that.

I am considering options here w.r.t. what would be legal and safe to prevent accidental flooding.

Option #1. Use something like kitchen sink rinser that has a built in shut off valve. My concern with this option is - are they reliable enough because they would be under pressure 24/7? Also, is there design that instead of simple on/off option would allow to control pressure flow?

Option #2. Use a cheap $10 water control valve. It is tempting for me to install it on the hose's side that has shower head opposed on hose's side where thermostatic valve resides. Mainly because then this water control valve would be in easy to reach place. And I would not have to deal with partially rotten wood frame where the old valve was installed. Are these valves reliable enough to be toggled multiple times a day?

Option #3. Get a shower trim kit with valve (similar to what we already had). Seems quite expensive, and I believe I would need to get one with only one inlet for warm water as water will be already premixed.

Any other options on how to control water flow?

If that's 1/2"npt on the valve, then they make flow control valves for showerheads that should fit. Usually around $10.

Just be careful, some are just on/off, and they look identical. Best to check with an experienced sales rep or read the back of you don't trust them.


How can I insulate behind pipes that are close to a foundation wall? Reading around, it seems like most people suggest to put up XPS insulation when finishing a basement.  That's great and all, but how do you put 2" of rigid foam behind pipes that already exist in the ground, sometimes as close as 0.5" or less to the foundation wall?

Cut the foam into manageable pieces and slide into place.  Use cans of spray foam insulation to fill the cracks in the sheets of foam caused by cutting.

Or spray foam the entire cavity and forget the rigid foam.


Can I use silicone lubricant on oven door hinges? After using my self-cleaning cycle on my oven, the door hinges squeak. What is safe to use to stop the squeak? I have used olive oil, but it does not last.

Sprayon has a food grade lubricant that should function for what you need.

Listing for this particular brand start around $11 for a can


Outlet looks like a NEMA 10-50 but is only stamped at 30 There is an electric stove plugged into this outlet. I can't tell what plug it is to make an adapter for car charging.

This is in the U.S.

It looks like a NEMA 10-50 all right, but it is labeled 30A.

Electrical Code 110.3 requires you obey labeling and instructions on every device.  Therefore, this mismarked device can only be breakered 30A, but anything you'd plug into it will pop a 30A breaker.   It is useless and must be taken out of service and tossed.   It may not even be a Proper NEMA connector, so a 10-50P may not even fit.  Not that you should be using a NEMA 10 to charge an electric car!  It invites a shocking situation.

The problem with NEMA 10

Even if you refit a NEMA connector, these large connectors are not intended for frequent plug/unplug. They will quickly take damage and terminals will start to break.   That's where NEMA 10 becomes a super bad problem.  They don't have a ground pin.  They are illegal for new work, but due to lobbying by the appliance industry, they are allowed to continue in service in older homes.  They "made it legal" to bootleg ground on ranges and dryers.

The problem is if anything goes wrong with the neutral connection, the chassis of the machine will become electrified. This has killed, and it's typically reported as a "miswired" dryer or range receptacle, however the receptacle was correctly wired.  It simply failed, which is a normal and common occurrence and it shouldn't fail deadly: it shouldn't electrify the chassis of machines. But it does, and that's what makes NEMA 10 dangerous.

Size up what you've got

Pop the socket cover  off the wall and take a look inside.  You want to know the size of the wires, and if they are aluminum, how many there are, and what colors.

First account for the hot wires.  There must be 2, either black or red.  Two blacks is OK.
Next, account for neutral.   If a white wire is present, that is neutral. It might be bare if it's the only remaining wire.  Sometimes it is a web of bare strands wrapped around the hots.
last, ground.   If neutral is accounted for, and there's still an unaccounted for bare, green or green/yellow wire, that is ground.  If both neutral and ground are present, that is awesome.   However ground can be retrofitted by installing a single wire -- neutral cannot.

Now look at the size of the wires, and we are concerned with the "hot" wires only.  They will be either 10 AWG, 8 AWG, 6 AWG, or possibly 4 AWG. (Getting larger as the number lowers).  This will be marked on the individual wires maybe, the cable sheath surely, or the diameter of the wires can be measured and look it up on the Internet.

Also determine if the wires are aluminum.  If they are aluminum, add 2 to the effective AWG. So #6Al performs like #8Cu.  Assuming copper:

if the hots are 10 AWG you must breaker for 30A and you must use 30A receptacles (not that one).
if the hots are 8 AWG you must breaker for 40A and use 50A receptacles (really).
if the hots are 6 AWG you must breaker for 50A and use 50A receptacles.

Adapt what you can

Now most likely, your car charger requires ground (uses a NEMA 6 hot-hot-ground or 14 hot-hot-neutral-ground). And most likely, your stove requires neutral (uses NEMA 14 or 10 hot-hot-neutral).  Neutral is not ground, no matter what you've been told.

But if you don't have ground, you can retrofit ground, simply by getting bare #10 wire and routing it via any possible means from the socket to the main panel, or any grounded part of your electrical system where the ground wire is #10 or larger, or  any non-flexible metal conduit that goes all the way back to the panel, or anywhere on the grounding electrode system (the bare wires grounding the panel to water pipes or ground rods). You cannot use random water pipes for grounding, with some exceptions.

The only receptacle which can satisfy both needs is NEMA 14, which happily also fixes the dangerous NEMA 10 situation.  Also happily, any range is designed to accept either a NEMA 10 or 14 cord, and can be switched just by changing the cord and removing the bootleg-ground jumper.

Your car charger is probably  wired NEMA 6 (hot-hot-ground), but it is perfectly legal to plug it into NEMA 14 with an adapter, extension cord with NEMA 6 and 14 on opposite ends, or just change the cord on the charger.

If your circuit is 30A, you can also have more than one receptacle on it.  So a 30A circuit could be extended to a new receptacle in the garage.  That is a no-no with 40 or 50 amp range/oven circuit.


Deck is moving away from house I have a 8 x 8 deck, attached to the house since initial build.
All in good condition, ledger and bolts, inspected and main boards repaired in 2014.

It sits in a corner on a 4 x 4 post, again in excellent condition.

The pad underneath has sunk a few inches and the deck has started to move away, splting the caulking from the house on both sides. [see pictures also].

The root cause was previous owners had not modernized the natural swale on one side of the property. Once this was remedied, and now we had lots of dry and wet cycles, and this is a symptom.

I am showing a 1/4" per ft tilt down, stressing wood around, door slider issues.

My plan was either

a) use a bottle jack with 4 x 4 [with 2 x 4 cross braces] on both horizontal beams, and then jack up incremently. Then then use insert wedge pieces above the support column and/or use an adjustable jack column as a secondary support, close up on the primary support beam.

Or,

b) jack the concrete 17ft x 6ft x 6” slab = 7650.49lbs + 1000lbs for deck, and use HD foam 250psi as shoring before backfilling around. proven method used here https://youtu.be/31uSPxKmBFA

Any feedback

The deck isn't pulling away from the house so much as leaning away from the house.  It's tight at the bottom and separating at the top.

It looks like the reason for that is the outside posts rest on a patio that is settling.  If you look at the third picture, you can see a wedge-shaped gap between the concrete patio and the step at the patio door.  It also looks like an additional gap under the slab at the lawn in that area.

Any fix you do to just the deck support will need to be redone when the slab settles more.  You need to fix that problem first.

There are two downspouts visible.  One dumps water right at the slab's edge, which is a problem.  The other goes into a pipe and where that pipe discharges isn't clear.  However, the picture makes it look like the worst settlement is in that area.  If that pipe actually discharges far away, then the issue may be that the pipe or downspout is full of debris and water is leaking out of the downspout higher up.

The downspout issues need to be fixed before you tackle anything else.  Water dumped next to the slab soaks into the ground and softens the soil under the slab.  You need to get that water far away from the house.  Even after you stop the water problem, there may continue to be some settling for awhile.

If there is also a grading problem, you need to fix that so rain water runs away from the house, and rain falling elsewhere doesn't run toward the house.

Once you stop the erosion, soil softening, and settlement, you can decide whether to jack the patio.  A single slab that size will be tough to jack, especially in a way that supports it evenly it's entire depth toward the house.  You could end up breaking it if you can even lift it.

You would likely need to excavate much of the edge, support broad areas of the slab with timbers, and use a series of bottle jacks to apply pressure across a large area at once.  But even if you lift it, I wouldn't want to support a slab that size by just slipping foam boards under the edge; that creates a lot of stress on the slab and it may crack.  There isn't really a good way to support it from the edge.

I've seen mud jacking and foam jacking used for big slabs.  That would provide support under the entire slab.  However, it can also settle after a few years, especially if there is still active settling of the soil underneath.

If it were me, I'd be inclined to leave the slab alone unless there is future evidence that it is still settling after you solve the water problems.  The slope isn't so much that it affects it's use.  The gaps, like below the patio doors, can be filled to keep the step supported and improve the appearance.

I would try to fill the gap under the slab edge at the lawn.  You can pack material under it by pounding it in.  It won't do much for support, but it will at least help keep stuff out of the gap, and maybe slow further erosion.

That leaves the deck.  You may want to do a potentially temporary fix until you can assess what's going on with slab settlement.  It looks like the support posts aren't actually secured to the slab, just resting on it.  If that's the case, I'm not sure it meets code and isn't very safe.  Someone more fluent in the code can get into that issue more, but without knowing code requirements, I can suggest what would at least be an improvement.

Use timbers and jacks to raise the side of the deck away from the house until it's level again.  Measure the gap you need to fill between the bottoms of the support posts and the slab.  Use squares of cement board (green board), the dimensions of the post, to fill big gaps.  Use plastic shims (back to back in opposite directions to create adjustable parallel surfaces), for small gaps, with enough shims side by side so the entire end of the post is supported.

Once the post is supported at the correct height, trim away any of the support material extending beyond the face of the post.  Then install brackets on the slab to constrain the post so it can't move laterally.


Adding Unused C-Wire for Nest Thermostat I'm having an issue with my NEST thermostat short cycling my air handler fan while in running AC.  This is a known issue, and the fix seems to be adding a common wire to the NEST.

My thermostat is wired with 18-5, and currently the yellow wire is unused.  I want to use this for the common.  Pic of the board is attached.  Humidifier and AC compressor are wired to board.

Can I just add the Yellow wire to the C terminal without changing anything else? I should probably pigtail the 3rd wire, correct?

Sorry for the dumb questions, I just want to make sure I've got it right.

Thanks

ETA: Picture of terminal block

Left to right: R C W Y G

It would be preferable to use the blue wire instead. The conventions for colors assign Yellow to cooling. The other colors also have standard assignments.

The Blue wire from a 18-5 bundle is what would be best for the C common.

If following recommendations to the letter, then the three wires connecting to C should be pigtailed.


Pulled a lot of stuff from Bath tub drain, now the clog is even worse! My bathroom bathtub was very slow to drain, water will stand in the tub for long time. I bought the 20 ft long auger (advertised for bathtubs) and I can't believe I snaked through about 12 feet deep and pulled a lot of disgusting stuff. I was sure the drain will rain smooth now.
To my surprise, it's now completely clogged and water will not drain at all.
I re-snaked and this time I am not able to get pass the first turn in pipes (about 2 feet or so). I believed when pulling it out first, it probably deposited a lot of stuff there.
What could I do now? I keep locking the auger and turning but pushing in but this time it's not going any further. Any suggestions?
I have a typical bathtub, I believe like this
Update
I used plunger and managed to open the drain that way but still wanted to snake it 2nd time but won't get passed the same point. The drain is working now though.

I have found (over many years and snaking hundreds of drains) that the ability to get past a bend in the line is directly related to your technique (read, experience) and the tool you are using.
Cheap cables are prone to flex too much and are difficult to get around some bends, especially if you've kinked it (although I keep a few cheap ones, I call them "noodles", for specific times when I need a soft cable). Also the cable size matters, small cable for small drain, larger cable for larger drain.
I highly recommend that you invest in a commercial quality auger with a cable that has a stiffening element in the core, like this:

I have owned the same one for >25 yrs. and have never encountered a home branch line (tub, shower, sink) that I could not successfully clear with it.


Unsure where to find "C" connection on furnace Another "don't have a C wire for thermostat" question. Been following along, and if I could identify the C connection at the furnace, I'd be all set. Unfortunately, it's not simply marked C or common. I have attached an image of the wiring diagram of my Utica MGB-2490 boiler. Am I correct in thinking that the blue wire terminating at the " PV  3" is what I'm looking for?
thermostat only had 2 wires connected to R and W (extremely old Robert Shaw mercury type), there is a 3rd wire tucked in wall, I followed bundle to basement, it is not connected to anything, could use for C if I am sure what to connect it to. Any and all responses are appreciated

You want pin 5 instead

The connection you want is pin 5 of the connector you have marked, labeled "24V GND" on the diagram -- it has a black wire running form it.  You can also tap the low-voltage junction between the white wire from the transformer and the black wires -- it's the same thing.


What should I do about a gap between hardwood and drywall? First-time home-owner - house less than 1 year old.

We had our home built last December, and have been discovering all sorts of problems with it. The latest was a trail of ants within our kitchen ascending from behind the stove. When we looked beneath the stove to see what the problem was, we found a small hole allowing sun-light in from outside. Our builder came and sprayed foam, but the ants have persisted for one more day.

I finally sprayed some insect killer behind the stove, and that greatly reduced the number of ants. Today I pulled the stove out to see what it looked like back there and found the following (see image). I'm noticing a large space between the hardwood flooring and the drywall - is this normal? Should I fill it with spray foam? If so, is spray foam enough to prevent further insects from finding their way in (assuming the initial round of spray foam wasn't sufficient), or should I deal with ants a different way?

If I should spray, what would be an appropriate product to use?

Killing the ants is one thing, and the comments from others are good.  However, you need to fix the root cause of the problem, which is hole that you can see daylight from.  Spray foam will only deter them for a while.  You should NEVER be able to see daylight through a wall from the inside of a home.  I would take a good look outside and see how much of a gap existed before the foamed it.  You may have to remove the siding to see everything, but I suspect the exterior wall may need to be patched.


Using Forstner bits instead of hole saws I have been having problems using hole saws when removing the plug of material after use.  Looking at What is the right way to clear the drilled plug out of a hole saw? it is still awkward and I have considered spending the extra on buying Forstner bits as an alternative.

But then I am told they are not for drilling all the way through.  Is it okay (or even safe or wise) to use Forstner bits in this way.

I'm not sure why someone told you that you can't drill all the way though with a Forstner bit, but in my opinion, they are incorrect.  These bits excel at creating a flat-bottomed hole but will also drill completely through the material just fine.  I regularly use mine in a drill press but they can also be used in a handheld drill.

I find that they splinter the material much less than a spade-type bit does although they are significantly more expensive.

Here is what Rockler says about them:

Rockler

  What's so special about Forstner bits?

  Unlike the standard twist bit, Forstner bits are optimized for
  woodworking applications and cut exceptionally precise, clean-edged
  holes in wood. Because they're designed to produce a minimum amount of
  tear-out when exiting the material, Forstner bits are the best bit for
  drilling through holes. Forstner bits drill a flat-bottomed hole,
  making them a necessary tool for many hardware installations where a
  precise depth of mortise is required. Forstner bits are guided by the
  wide outside rim of the bit, unlike most drill bits, which are guided
  by the tip. Because of that, they can be used along with a drill press
  to drill angled holes, holes that partially overlap, and holes on the
  edge of the material.


Is this a drain fly? The fly/moths have been increasing in my apartment. All my windows are closed. All summer there would occasionally be a few in my bathroom, and in the past week I sometimes come home to find tens of them in my kitchen and bathroom.

Picture is below, they don't appear to be drain flies from photos I've seen online. Any help appreciated.

It's a fuzzy picture, but it appears to be the type of moth that is the adult form of a "meal worm", called a "meal moth" or "Indian mealmoth". You likely have some opened bag of wheat or corn meal somewhere that you rarely use and it had meal worm eggs in it, which are almost microscopic and nearly impossible to remove in processing. Those eggs hatched into larvae, the "worm" stage, now those larvae have grown up and into their adult moth phase, where they only live a few days as they look to mate and make more babies.
https://en.wikipedia.org/wiki/Indianmeal_moth


Metal screw stuck in middle of deep plastic (resin) hole I was trying to tie something that has a deep hole (around 7 cm). I tried one screw that has stuck in the middle of the hole. I thought that the screw will come to the end but it didn't as its head is wider than the hole diameter. Now the screw's head is stuck in the middle of the hole while its tip is out of the other side of the hole. I can't get it out or push it further to the other side of the hole. This hole is a simple cylinder.

Any ideas how can I solve this situation? This thing I'm trying to hang on the wall is so important to me.

I would push the screw out the way it went in. That is I would use something soft like a wooden dowel to push against the point of the screw. It may help to first drill a small pilot hole in the end of the dowel that the point of the screw can go into, then turn the dowel clockwise as you push it in. turning the dowel has a chance to turn the screw and this will help the screw head move out of the hole.


Possible to use trim with routed out channel to hide 12/2 or 12/3 wire instead of using Wiremold? I plan to add some lighting in positions on the ceiling that doesn't have nearby wire available.
The there is no free space between the ceiling/roof in which to run a wire (there's the wood, then solid foam block insulation, then weather barrier, then the shingles). So, I would need to run wire (12/2 or 12/3) to that location somehow. I'm aware of Wiremold, but that wouldn't look very good with the style and material of the ceiling itself.
Is it possible, instead, to run the wire through a 0.5" channel routed out of a 1x1" piece of wood and affix that wood to the ceiling? I read through California electrical code (I'm in San Bernardino County, California), but didn't see anything specific around this (unless I missed it, or interpreted it incorrectly).
Thanks in advance.

No, you can't do it unless there's a "nail plate" to protect it from physical damage (nails).
You could mill it out to 15/16" and lay in EMT metal conduit.  It has the thinnest wall of any conduit and will provide the needed physical protection.  Use that either simply as a damage shield in the vulnerable area, or if able, as a full-on wiring method for the entire route.


Why not put a vent that pushes air from the attic into house? I have this idea, and since it seems logical to me, but I don't see it anywhere I suspect I am missing something.. so here it is:

Why not put a vent that pushes air from the attic into house?

At summer, everyone wants to exhaust the hot attic air outside, makes sense.
Winter time, the attic still gets hotter, quicker, on cold *sunny day then my house (because I have little direct sun into my house, but also in any well insulated house).
why not use the greenhouse "attic" effect, and have a vent sucking the hot air from the attic into the house? you could have that fan linked to a thermostat, only pushing air when attic temp >  house temp...

seems easy and cheap, what am I missing?

Aside from the fact that your attic can be very dirty, you need to be concerned about the following:

If you have any gas heating equipment in the attic (central heat, water heater(s)), they may not meet regulations to allow them to be connected to the house's main air supply. You can run a major carbon monoxide (CO) risk from improper ventilation of gas-burning equipment.
Pest control companies can use harsher "dusting" pesticides in attic spaces - stuff you really don't want joining you in the house. Insulation is often loose and can irritating. If you have a much older house that might have asbestos insulation, then you have other problems as well.
When you pull air out of the attic, it's repopulated by the air from outside. If the air outside is very cold, your attic could reach new low temperatures, freezing pipes or causing other damage. (This may or may not happen, but it's something I would make sure of before attempting this.)


Tempered Glass Tabletop - Safe dimensions for a given base? Sorry for the confusing title. We have a circular table (an old etched wheel) that is 3ft in diameter. It also has 4 rubber spacers along the diameter. I want to get a tempered glass tabletop for it. Our old one broke when someone placed a hot dish on it. The old glass had around 3ft 6inch diameter and about quarter of an inch thick.

My question is this:
Would a 12mm thich, 4ft diameter tempered glass tabletop be safe?

Our table would end up having a 6 inch glass ring around our current table. Would that be safe for dining purposes?

Here is a photo of the table and a photo of the rubber stoppers.

If you use only four support points, your glass top is actually sitting on a square about 2.12 feet on each side. So your overhang for a 4 foot circle is about 11 on each side.

Tempered glass is very strong (note that annealed or hardened glass is also strong, but much less so than tempered). This calculator suggests that a 1/2" tempered glass shelf 11" x 25" supported at the ends would withstand a weight of over 600 lbs. The pressure on your table edge is somewhat different, since it is supported only along one edge, but that edge is attached to the rest of the top. It sounds as if there is little danger of the unsupported edge breaking off.

The bigger risk is tipping. If someone leaned on the edge of the top in between two of the support points, you have a lever of about 1 foot lifting three fee of tabletop. The top would be quite heavy (maybe 80+ lbs.) and would take a lot of pressure to tip. But it is quite possible, say if someone sat on the edge.

Consider adding several more support points around the edge (at least 4 more).  This would increase the supported area to nearly 3 feet, and reduce the unsupported section to just over 6 inches.


Replacing light switch with dimmer switch... white wire? On a three gang switch, I'm replacing a single pole light switch with an electronic dimmer and a second single pole light switch with a WeMo switch.  The third switch is getting replaced with a similar switch.  The current configuration into each "old" switch is black, black(red) & ground.  There are 4 white wires from the wall not attached to any of the three switches but grouped together.  Both the dimmer and the WeMo switch ask for a neutral white wire.  My question is "can I group all white wires together (from dimmer and from WeMo with the 4 white wires from wall) or do I need to identify the white wire specific to the WeMo switch and the white wire specific to the dimmer switch instead?" In other words, instead of 6 white wires together (WeMo, dimmer and 4 from wall), would it be 3 separate white wire connections (WeMo white with white from wall, dimmer white with white from wall, and the rest of the whites grouped together).  All three light switches are on the same circuit, by the way.

Since the 4 white wires are already connected, they need to stay connected.  It would be correct to wire all 6 whites together.  Note that for 6x #14 wires you need to use a new red wire nut.


How can I test network and coax jacks? We bought new house and I need to test network (RJ45) and coax jacks to see which ones are working. How can I do that without actually connecting computers/cable boxes?

Very good question but you need to find out more information.

The very first question on my mind is.. Where do they connect to ? if they are connected to anything else at all?

A simple solution

Find the starting point(A) and the end point(B) of either cable.

Using a multimeter and a *return cable** you test continuity of the cable. Either using Ohms = 0 which means short circuit(in this case good because the cable is good) or some meters have buzzer if there is continuity.

You can also test the cable without a return cable, by joining the ends (centre and shield- or a pair) at one side and testing the centre core and shield on the other. This will test the entire continuity. If there is no continuity - which means the cable is broken - then you would not know if its the core or shield. But at least you will know the cable needs replacing.

RJ45 Network cable used for 10/100Base Networks.

This is very time consuming because RJ45 have several strands of cable so testing one after the other can be beach. But one clever solution is to make a loopback on point B and test the corresponding points on PointA. If it does not loop back then the cable is most likely broken.

There are also network testing equipment that do the same as mentioned above.. but you have nice flashy lights and a nice loopback box supplied.Ebay a few bucks each for el cheapo ones.

COAX

Coax is a funny one and depends on what you need it for. Coax for TV, satellite or CCTV again. On digital signals you might get choppy or images cutting in and out if there interference. On analog you will see allot of "snow" or shadows. It is best to replace or check the fittings to see that the connections are good.

But you can test the cable also ...

Center to shield (No Ohm reading - No beep)
Center to Center (Short/Continuity - Beep)
Shield to Shield (Short/Continuity - Beep)

An extra step here (1) is to test for short circuit between single(centre) and (shield) without and return cable or joining any end. This will check if there is a short circuit on the coax.Possibly a nail or screw when right through the cable.

The other part if its used for a network then it all has to be connected and terminated to test it(but its unlikely its used for network because these types or network have been eradicated because of unreliability)

REMEMBER

This will only test if the cables are in an operable state. So you connect it and it will work. The bandwidth, noise-to-signal and interference will greatly depend on the quality of the cable, workmanship during installations, etc.

EG
The RJ45 could be rated for Gigabit but your bandwidth could a mere 250mbs(1/4 bandwidth) because the shielding has not been done properly, or the ends have been poorly installed, the cable is near high voltage lines, the cable is severely bent ins several places along the way.

COAX in general either works or not.But for Analog Video; again many factors come into play. For digital(eg satellites) it should be ok

*return cable - A long piece of wire that you know is OK. You will attach this at Point B and run it freely back to your meter. This way you can test the continuity of a single core.


Why GFCI clicks, even when turned off? I have a GFCI receptacle that is clicking. Every 5-10 minutes it clicks repeatedly for 1-2 seconds. The GFCI is turned off (the RESET button is sticking out) but it still clicks! What does this mean?

It's in an RV that is connected to shore power through a few long extension cords, total ~200 ft., plugged in to a GFCI receptacle by the meter base.

It's a bit windy right now, maybe that is triggering something.

It suspect there's a loose connection somewhere the system, maybe that is the cause.

Where should I begin diagnosing the issue?

I'd wonder if the GFCI is detecting a fault in the wiring coming into the outlet.  The first step is to verify it's the power by unplugging from the metered base.  The next step, for me at least, would be to verify the GFCI in the meter with a simple tester that includes the GFCI button on the side (assuming it's a 110v style plug, not sure if they make them for 220v).

Make sure your extension cords are a high enough gauge to handle that distance for the number of amps you expect to pull, and be sure to replace them if they are showing any wear.

And if all else fails, replace the outlet (taking careful note of which side the wires are feeding the outlet, and which lines may be daisy chained off of the old GFCI so you can rewire it the same way).

Edit: [From your comment on the extension cord.]

Corrosion could have been the problem.  GFCI detects a leak in current, not necessarily going to ground.  So if there is a bad connection due to corrosion, that might appear to be a leak.  Also, realize that most fires are caused by arcing, and so AFCI are becoming common, which will detect more than GFCI.  That may be what's in the RV, and the reason it caught the issue before the base receptacle.

http://en.wikipedia.org/wiki/Arc-fault_circuit_interrupter


How many computer chargers can I put on 1 electrical outlet? I am trying to create a computer charging station. I have many laptops and Android Tablets that I would like to charge at once.  Assuming I wire it correctly, how many adapters can I put on 1 plug?

Laptops are 40W charger cords.

Tablets are 10W charging blocks.

36 laptops,
or
144 tablets,
or
18 laptops and 72 tablets,
or
Any combination of laptop and tablet that is less than or equal to 1440 watts.

Since a 15 ampere 120 volt circuit can supply a maximum of 1800 watts, but a circuit should only be loaded at 80%.

15 amperes * 120 volts = 1800 watts

1800 watts * 0.80 = 1440 watts

This example assumes that this is a dedicated circuit, with no other loads on the circuit.


How to find replacement toilet seat (American Standard) How do I determine what seat will fit this toilet and are colored seats available?
Inside the tank are these numbers:
1459
388
M59
Aug26

Thank you.

Toilet seats are available in a variety of colors and materials, plastic, wood, padded. There are dozens if not hundreds of options.
Your toilet appears? to have an elongated bowl, as opposed to a standard bowl, so you need to make sure you get an elongated seat.
Most seats are universal fit, except for some custom toilets, so you should be able to buy an elongated seat, or a standard, in a color you like. Just two bolts at the back of the seat go though two corresponding holes in the bowl.
You can get soft close hinges to keep it from slamming down.
Example seat.
Vintage Bermuda Coral Toilet American Standard Compton 4043 Pink Retro One Flush
OR
Mid century "Standard" toilet, Pink
That's right, i have nothing better to do then spend time looking at 50 year old pink toilets on the intertubes. ;)-


Can my water heater's relief valve discharge line and drain pan line merge into a common pipe? Currently, I only have a T&P relief discharge line that runs down to just above the pedestal and out through the exterior wall. I would like to install a drain pan under the water heater.
I want to cut my relief discharge line and install a tee in order to connect my drain pan's line and allow both to exit using the existing pipe. My concern is that this might allow water flowing down from the relief valve to flow back into the pan and overflow it.
Is this a recommended solution?

The answer is no. This configuration would most likely fail multiple code requirements.

Explanation

You do not mention the diameter of the current discharge pipe, the distance that it runs, how many changes in directions there are, and where it terminates, so I cannot provide a complete answer. However, I can confirm that it would be against code to directly connect the two pipes together due to the resulting cross-connection between a potable system and a drainage system.

The pipe that drains the pan is considered part of a drainage system (either sanitary or storm, depending on what it connects to or where it terminates). The T&P relief valve’s discharge pipe is connected directly to the potable system and as such is
considered as part of the potable system. It is against code to directly connect these two systems as the resulting cross-connection allows for the potential of the potable system becoming contaminated.

In addition, there are pipe diameter requirements to be considered.

In a typical installation, the relief valve’s discharge pipe terminates indirectly above the drain pan’s drain opening with an air break that prevents the two systems from being cross-connected. The requirement for a drain pan’s drain pipe is that it be 2 times that of the relief valve’s discharge pipe diameter.

I assume that the diameter of your T&P relief valve’s discharge pipe is the same size as that of the T&P valve’s outlet connection, therefore this pipe cannot be used as the drain pan’s drain pipe, unless you increase the size of it.

Suggestions

You could repipe the drain line to outside in a larger diameter and install the drain pan and T&P discharge pipe as outlined in the below code requirements. (Note that if your drain is to discharge outside above grade, that in addition to it being located in a safe place to prevent anyone from being burned, you should also put some sort of screen protection on the end of the pipe as this pipe will create a direct opening into your home via the drain pan’s opening)
If the water heater is located in an accessible location, the combination of periodical visual inspections and turning off the tank and shutting off the water supply when being away on vacation, will prevent most issues with water damage from a failed tank. In addition, replacing the anode rod as outlined in the tank’s literature will prolong the life of the tank.
If you are really concerned about water damage from a leaking tank, there are many leak detection systems that when sensing a leak can shut off the water supply.

Code Requirements (Based on the Canadian Plumbing Code)

Relief Valves

Every hot water heater mush have a pressure relief valve and a temperature relief valve. The two can be combined in one device so long as it meets the requirements for both individual valves:

operates when the pressure inside the tank reaches the rated pressure of the tank
located so that the pressure in the tank cannot exceed the pressure in the tank by 35 kPa (5 PSI)
located within the top 150mm (6”) of the tank
is designed to open and discharge sufficient water from the tank to keep the temperature of the water inside the tank from exceeding 99°C (210°F)

Relief Valve Discharge Pipe

The requirements of the relief valve discharge pipe are that is must:

be of a size at least equal to the size of the outlet of the valve
be installed ridged
be piped so that it is sloped away from the valve
terminate with an indirect connection above a floor drain, sump, or other safe location
have an air break not smaller than the diameter of the discharge pipe but with a minimum of 25mm (1”) or a maximum of 300mm (12”)
have no threads at its outlet
be capable of operating at a temperature of not less than 99°C (210°F)
have no shut-off valves installed on it

In addition, if the relief discharge pipe is longer than 2m (6’ 6”) or if more than two 90° elbows are used, the valve manufacture’s installation instruction must be followed to ensure that the piping does not restrict the valve’s discharge capacity.

Drain Pan Requirements

A drain pan is required when a hot water tank is located in a ceiling or roof space, or over a floor of wood construction. The requirements of the pan are:

be not less than 50 mm (2”) larger than the tank
have walls not less than 25mm (1”) high
be drained by a pipe two sizes larger than the relief valve discharge pipe
have a drain that is located directly under the relief valve discharge pipe that drain directly to a floor drain or other accessible location

Typical Hot Water Tank, Relive Valve, and Drain Pan Configuration:

           ___
   _______|_  |
  |         | |
  |         | | <— T&P Discharge Line
  |   HWT   | |
  |         | |
  |         | |
  |_________|     <— Air Break (end of pipe to top of pan wall)
|_______________| <— Drain Pan
             |  ____________ <— Drain to Sanitary or Storm System
             |_|

Note: if the drain pan’s drain connects to a sanitary system, a p-trap (as shown) is required. In addition, the p-trap would require a trap primer.


What can I use as a guide for my circular saw if I need to rip an 8' segment out of a sheet of plywood? I need to cut some plywood down to size and it will require that I take it down from a 4'-wide sheet to 30" wide.  This means I will need to find a saw guide that will support a steady, 8' rip from end to end.  I am not finding any 8'-long guides and am wondering if I am going to have to make one out of scrap plywood.  The thing is, I can't be 100% sure that it would be completely straight.  It would be much better to find a guide that is built for longer rips.

The factory edge on a fresh sheet of plywood is very straight. So use that.

Option 0: Snap a chalk line and cut by hand. Fine if you're doing sheathing, but not accurate enough for many other tasks.

Option 1: Use 2 sheets of plywood. Stack one on the other, offset by ~32". Use the top one as a guide to cut the bottom one.

Option 2: Make an 8' ripping guide.

You'll need the factory edge of a sheet of plywood, the full 8' long. Approximately 6" wide. Thicker is good. This will be the guide.

Also, a piece of doorskin (single-ply, 1/8" plywood) or 1/4" plywood, 8' long, approx 8" wide.

Glue & screw them together. Make sure to countersink the screws slightly.

Run your circular saw along the factory edge of the thicker piece, to cut the thin lower piece to match your saw.

Now you can put the fresh-cut edge on your material and know exactly where it will cut.

This jig is specific to the saw you used to make it.

There are many videos covering this on YouTube.

For bonus points, make it double sided (one narrow, one wide), so you can cut on either side of your circular saw.

Option 3: A guide that attaches to the saw, like the Kreg Rip-Cut

Option 4: Festool Track Saw These circular saws fit on special tracks to make straight cuts. Not only do they cut through heavy, thick wood with ease, but they cut through wallets even faster!


How to get to blown light bulb I am not sure how to actually remove the casing so that I can get to the bulb that has blown?

without breaking something...

I can't be certain from the image provided but it looks like an LED fixture. A lot of times those LED fixtures are made to not have a replaceable bulb (IE the bulb is built into the fixture itself). If that is the case, then the whole fixture would need to be replaced. If you don't have open access to the ceiling (in the case of an open attic above or the like) it appears you need to pry the metal plate off to access the rest of it. Before doing that maybe try turning the plate to see if it unscrews or detaches from a locking mechanism.


Does an outdoor hot tub receptacle and breaker both have to be GFCI? I know outdoor receptacles have to be GFCI, however my hot tub manual specifically says the breaker should be GFCI (does not mention the receptacle). I know there is also a GFCI near the hot tub motor as well. If the receptacle is already GFCI, does it make sense to have a GFCI breaker as well, isn't that a waste? I suppose I could only use a GFCI breaker and not a GFCI receptacle outside, but inspectors seem to frown on that and it's a pain to reset all the way in the basement if there's ever an issue. I'm in New York State USA.

GFCI is not a receptacle or breaker.   It is a zone of protection provided by the GFCI device.  It protects everything down the line from the GFCI device.

Sometimes the GFCI device itself has a couple of convenience outlets that are on the protected side: a GFCI+receptacle combo device.  This is what you mean when you casually say "GFCI", because this is the most visible form of GFCI device.

You are also familiar with the GFCI+circuit breaker combo device. This obviously protects loads downline, since it has no convenience outlets of its own, just two "LOAD" terminals.  GFCI+breaker combos are $40-ish.

Then there is the GFCI-only (not a combo) device, a "black box" which does only the GFCI function.  It has two LINE inputs, two LOAD outputs, and that's all.  It typically comes in a rather familiar looking package, hence the slang term "deadfront".  Deadfronts are about the price of the cheapest GFCI+receptacles since they don't need child-safe sockets nor outdoor rating, around $15-18.

Since this is a dedicated circuit for 1 appliance, you also need a single plug. Common and $5 in plain sockets - rare and expensive in GFCIs.

Why do we care where we protect?

First, are the wires protected?  If the GFCI+receptacle gets wet, or water gets inside the box, water can contact the non-protected wires directly. The GFCI tripping won't help you at that point. Not an issue with GFCI+receptacles upstream.
A GFCI outdoors is also ravaged by the elements and will have a much shorter service life, which is a shame because it also must be an "outdoor-rated" GFCI at extra cost.
Anti-tamper safety doors over the blades are required, these are much cheaper on plain receptacles than GFCI receptacles.
Cost -- GFCI+breaker combo devices are around $40 and you are married to your panel brand*; if your panel is an obsolete like Pushmatic, you're out of luck.   Deadfronts cost $15-18 + $5 for a plain breaker.  Outdoor rated, anti-tamper GFCI+receptacles cost $25+.

* Siemens makes breakers specifically for Square D QO panels; and UL lists them for QO panels only (they don't fit Siemens panels). However they are not any cheaper than Square D's QO breakers, so these "classified" breakers are a waste of time. So Don't mix and match brands, even if they "seem to" fit.


Should I remove the 2x4 between the joists of this deck? I'm working on replacing the decking on an existing deck. While removing the old decking, I came across something I've not seen before. I've seen decks framed as illustrated below, where members are attached to posts to allow joists to be hung.

(This likely isn't a code approved method of building a deck anymore, but I'm not rebuilding the entire deck to fix it.)

The thing I don't understand, is that they added a 2x4 laid on its face between the two beams.

I'm not sure why they added the 2x4, maybe to stiffen up the "beam", or just as a nailing surface.  Unfortunately, it works great at trapping water under the decking. All the decking that was in this area is rotten, and the whole area is damp (despite not having rain in about a week).

I've never seen a "beam" built in this way, and I'm a bit perplexed. Can I remove the 2x4, so that water is not being trapped?  Is it there for some structural reason?

I see no reason for that board, but a photo would help clear things up. I also assume that the joists are hung on the beam using standard steel hangers and approved fasteners. If all that is correct, you should be able to remove the board.

I'd guess that it was added to support decking joints that fell over the beam. Presumably the decking ran parallel to the beam. A better approach would have been to put individual blocks in that essentially carry the joist through the beam gap.


How to properly attach copper pipe to steel framing? What is a code-approved way to secure copper pipe to metal framing members which minimizes heat transfer and potential reactivity between the two different metals?

You use plastic bushings. I couldn't find a photo with pipe, but here's one with electrical:

This gives you the benefit of separation of materials and also a 'slip joint' to handle the expansion/contraction of pipes so they're not making lots of noises rubbing against framing members.

To attach the pipe to the stud, you can use pipe clamps like this:


Can I move my bathroom sink's drain pipe about 6 inches to the right? I found the vanity I wanted for my bathroom, but it doesn't fit due to the position of the drain pipe.  It needs to move about 6 inces to the right.  I assume there is some sort of adapter or something that can be used for this, but I know approximately nothing at all about plumbing.  Can this easily be done by the naive DIY'er?  How would I go about determining what size PVC pipe I will need, etc?

Yes... Maybe... It depends...

The pipe can defiantly be relocated, the question is how difficult will it be.  It may be as simple as opening the wall, cutting out the old plumbing, adding a few fittings, and closing the wall back up.  Or you might find there is framing in the way, or some other complications.

It's nearly impossible to accurately answer your question, without being able to see what you are dealing with.  The best anybody can do without seeing it, is say yes it can probably most likely maybe be moved.

If you're not sure what to do, or don't feel comfortable doing the work yourself. Remember, your friendly neighborhood plumber is just a phone call away.


Can I increase the length of LED RGB 5050 tape? I see that there are a lot of experts on this forum, so I believe that someone will be able to help me with small LED lightning project (I have bought/will buy all components on eBay).

Currently I have the following parts:

5m LED RGB 5050 Strip, 60 LED/meter
LED Controller (with 44 key remote) 6A Max. output
Power supply DC 12V, 5A

I'm quite satisfied with it (brightness, colors, etc.), but I would like to extend the overall length to 9 meters. I have seen on forums that for bigger lengths of LED tape it is necessary to add amplifiers to compensate voltage drop on the end of tape. As far as I have seen, each LED consumes max. 0,24W. If there are 60 LEDs per meter, it means that maximum power consumption of complete tape is 5*60*0,24=72W.

So, to add additional 4 meters I need to buy several things

Additional 4 m LED RGB 5050 Strip, 60 LED/m
Amplifier For 5050 RGB, 6A Max. output.
Power supply DC 12V, 8A (I plan to buy a bit stronger power supply).

At the end I plan to connect averything according to schema below.

My questions are:

Do you think it will work ok (no overheating on any place in schema) if I connect it this way?
Could there be any problems if I put a bit stronger power supply for first tape (I have read that the power supoply should be 10% stornger than the maximum possible power consumption)?
If I connect power supply which has max. output 8A to controller which has 6A max output, could there be any problems with it?
Generally speaking, is it a problem if you have weaker power supply than the max. possible consumption on connected component? I suppose that everything is ok if you have stronger power supply than max. possible consumption on connected component.

I'm not familiar what that product specifically, but the "amplifier" in this type of lighting setup generally only reads the input from the previous upstream light strip and provides power from its power source. Therefore, the amplifier draws no current from the upstream lights.

Instead of 2 power supplies, you could use one power supply larger enough to satisfy all of your power needs.

To answer your questions specifically:

Yes.
No. Power supplies are rated for the current that they CAN deliver. Using a power supply larger than needed is fine.
Again, not knowing these devices specifically, I am going to guess no based on my experience with other, similar products.
Generally no, provided you do not draw more power than the supply is rated for.


Can I put plywood over the drywall on the common wall between my house and garage? My garage is attached to the house.  The wall that is common with the house is finished with drywall.  Can I put plywood over the drywall?

I think I am accurate in saying this.... As long as you keep the drywall layer at the house/garage, and do not damage it in any way (screws ok) you will not compromise the fire rating of the original sheetrock. The drywall at that wall is a requirement for fire safety, it is typically a thicker, 5/8", and fiberglass reinforced to withstand a potential fire in the garage for a time before it spreads to the house.


Wiring C-wire in old Rheem looking for some help with an old Rheem 1005 HVAC system. I’ve scoured the Internet for days, so this is a last ditch effort at self-help. I’m installing an ecobee to an existing 4-wire system that had a 5th C-wire already available at the thermostat. The thermostat is hooked up completely but I don’t know if the c-wire is connected at the other end in my HVAC control board because if I turn the ecobee on, it just cycles over and over and Shorts out or something, then immediately kicks back on. The inside of this unit looks like nothing I’ve ever seen before.

I just need to know if that loose blue wire is my C-wire and if so, where can I connect it, or if I need to wire a new c-wire.  Pictures are attached for reference.

No, the loose blue wire is a 208V tap. The C wire comes off the other side of the transformer. I highlighted the blue 208V wire you referenced, plus the C wire (yellow) in your schematic:

It's one of the two yellow wires, which go to another area (not pictured)

It actually doesn't make a difference which yellow wire is which (AC voltage, so no polarity) -- one goes to the "R" terminal (power, usually red) and the other is "C". From the schematic, you might have only 4 terminals for the thermostat, but there at least does appear to be a hookup for the C wire.


Single phase hook up to 3 phase box I have a customer that wants to install a single phase 120/208v coffee brewer to a 3 phase panel. Can this be done safely? The unit uses 220v for heating elements and 120v for control board.

Single phase power is just one (or two) poles of a 3 phase system, ALWAYS. So no, there is no "safety" issue, it is done all the time. The only issue is that it MIGHT be that the heating elements inside of the coffee brewer are configured to be connected Line-to-Line, instead of Line-to-Neutral. If so, then they will get 208V instead of 240V. Since the elements have a fixed resistance, the wattage output of the elements will drop to 75% of what they are rated for at 240V (P = V squared / R). That then will mean that it will just take longer for it to heat up the water.


What are the pros and cons of frameless and faceframe cabinet designs? My wife and I are trying to decide on the two styles of construction...durability and cost are the major factors.

What are some other pros/cons of each?

One pro/con we've been struggling with...
At our local big box hardware store, the designer there helping us tells us that frameless cabinets (such as at IKEA) are not as high quality. Also, b/c they are generally made with particleboard (with a veneer finish) and the hinges mount directly to the cabinet box. If the mounting area of the wood gets damaged, you essentially have to get a whole new cabinet box. And if that happens to be a base cabinet where counters will sit on top of, that will be a difficult swap out.

On front face cabinets, the hinges are mounted to the front face frame. If the wood at the hinge fastening is damaged, you can just replace the front face frame.

The particle board cabinets are cheap. If you ever have a leak in the sink they swell up and start falling apart in a very short time. The cabinets that are made out of particleboard usually do have the hinges screwed into the face when the particle board breaks there is no way to really fix it to look good (without repainting /or a new veneer- Cut the damaged area out put in new wood and a reinforcement on the back side).
The cheap particle board cabinets will look nice for a while but not last like plywood. Several weeks ago I was in a house that I helped remodel over 35 years ago with my father. These are solid plywood with birch or oak veneer, My aunt said they did have to replace the hinges (self closer) as they had worn out. They also sanded and added a new coat of varnish. the cabinets look great other than being "style dated". I know over the years I have removed quite a few bathrooms and kitchen cabinets that had gotten wet that were made out of particle board. There have been a few that the owners just wanted all new looks that were plywood (many of these I used in my shop & friends garages). If durability is a concern don't even think of particle board. if you have Pre-teens don't even think of particle board. If you are an older couple (no kids at home) and the budget is more of a concern Particle board may be ok. This is my opinion others may disagree but I rarely see 20+ year old bathroom cabinets out of particle board and many times the "sink area" in kitchens has been damaged in much less time.


How do you remove a dummy knob with a screw that seems to spin and spin? I recently purchased my first home and wanted to replace all of the door knobs to make it feel more like my place, rather than just some place I was renting again.  Anyway, all of the privacy locking knobs, closet knobs, and even the deadbolts on exterior doors were pretty easy for a novice like me to remove and replace.

Unfortunately, there are a lot of closets in this condo and therefore there are a lot of dummy knobs that need replacing.  I thought these would be the easiest to do, but I was hit by a curve ball:

The dummy knobs that came with the condo seem to have an extra screw - beyond the two that you can unscrew from the front.  This third one goes from the back of the door, through a washer, then through a hole in the door and into the knob.   I tried to unscrew it, but can't seem to get anywhere. It just sits and spins.  This leads me to believe there is some kind of nut on the inside of the handle, but I have no idea how to access this nut (or really, if I'm even on the right track).

Am I missing something?

After removing the two screws on the handle, you may need to pull on the handle (away from the 3rd screw) to provide some resistance so the screw can begin unthreading.


Trying to wire a new light fixture in the bathroom - what is going on with these wires? In my bathroom, I currently have: one electrical outlet, one light fixture, and one fan. There are two switches at a 2-gang box (for the fan and the light). The fan is a simple fan without any other lights or speakers or anything.

I already set in the new light fixture and ran the wires through the attic. I am about to fish them down to the light switch box, planning to change it to a 3-gang and add a third switch.

But I found I don't quite understand the existing wiring. Specifically there is a red wire hooked to the fan's circuit in a way that is confusing to me. To accomplish my task, I was just going to wire a new switch to connect to the hot "line in" as well as the light, with the white return from the light going to the rest of the whites. But I wanted to make sure I understand the rest of the wiring.

Here's are diagrams: 1) what I observed in the box, and 2) what I infer is going on as well as my question regarding the wiring.

I did not follow your question completely so I will explain how it should work (per code) A switch leg is where the power is supplied in the attic and then the hot black feed from the attic normally would go down on the white and come back on the black/ red after the switches. All work is done with the breaker off.

you have a fan and a light so at the switches you take the white to both switches (they should be marked as hot black or other color not green) then your red goes back from 1 switch and the black from the other switch.

At the attic tie the light and fan tie the neutrals (white) to the cable from the panel your supply white or neutral.
the fan hot to the red (or black)
The light hot to the black (or red)

The hot black from the panel to the white going to the switch (on the 14-3) this is always hot so it is harder to get confused but the white wire should be marked as a hot like the switches.

This would be the proper way to wire a switch leg to 2 devices through 2 switches.


How to fix leaks in concrete and steel bulkhead I have a bit of an urgent situation forming. I recently purchased a house that's 55 years old, with "no history of basement leaks." Long story short - my basement flooded yesterday during a small rain storm. There was damage to stored boxes and it was quite a mess to clean up. Today is Tuesday, and we are expected to get major rain for four days starting Saturday. That gives me four days to find and fix the issue. I didn't see the water coming in, so I'm not 100% certain where it's leaking, but I have a few likely suspects.

I have time to do this job only once, and need to get it right. Correct product, procedure, and application the first time - or more flooding will occur. I've taken and marked several photos and I'm hoping for some advice.

I think the majority of the water is coming in though this old buried wire that's below grade. The outside end got snagged on a trencher last fall, and I think it may have pulled and broke previously applied sealant.

There are also several long cracks that have been previously sealed by the former owner. They are much deeper below grade, so I'm not sure if they'll leak once the higher holes are plugged. Some of the sealant seems to have come away from the foundation, as there are openings behind it. I've highlighted the location.

Finally, when we look outside there are issues too. The previous homeowner installed some edging bricks, and I just noticed that sit about 1/2" proud of the grade. There is an inch of stone in the middle with some landscape cloth underneath. I suspect this only serves to keep water from running away from the foundation. My land slopes away from the house slightly, so it's graded well. I think this is becoming basically a swimming-pool when it rains.

This is my current plan, but I'm open to any and all suggestions.

Tonight, I'm going to flood that area with my hose and mark where water in infiltrating.
I need to find and buy product to seal both the foundation and/or bulkhead.
Friday, I plan to remove the edging bricks and remove the stone and fabric. Dig down to expose the wire and remove it. Plug the hole and seal.
Scrape away loose sealant from the foundation and reseal. I'm hoping I can do this from the inside only, since digging down that far on the outside will be a huge chore.
Build up the area around the bulkhead with topsoil to run water away from the area, and extend the gutter discharge about 18" away.

Does this sound like a plan that will work? I basically have one shot here before I'm in sump-pump territory.

In the end - the issues was as I expected. I saturated the area with my garden hose and observed where the water was coming in - which was mostly through the wire penetration.

I dug down to below the wire and removed the wire. I scrapped away the old sealing that had failed, and then used an angle grinder with a flap wheel to bring the hole to bare metal on both sides.

I created a rivet of JB Weld SteelStik and pushed it through the hole, smoothing it with my thumb on both sides. Once that had set - I coated both sides in a thin JB Weld Steel Epoxy. When both had dried rock hard, I painted them with metal primer.

For the long cracks - I scraped out the old sealant that was failing - and used the angle grinder again to clean the area out, removed rust and even the faces where the metal touched the steel. I filled the whole area with Dynaflex 230 waterproof sealant. I used a chip brush to really force the sealant into the crack and paint it on to the area. I then used a rubber detail tool to press it in, and smooth the bead.

I got a big rain storm 2 days later, and everything I fixed held bone dry, but I did find 1-2 other small leaks that will need to be fixed used the same techniques.


Trying to understand why a light would be wired this way? Just moved in to an older home with fiancé and WAS planning to change out a light fixture with a new ceiling fan. However after turning off light switch and breaker and proceeding to remove light fixture I ran into something I felt was strange and later confirmed was very strange to a novice such as myself.

When I removed the fixture to expose the wires I discovered it was connected to two white wires. Not the single black / white I expected and that was at the switch.

Both black wires were taped up together and not used.

I also got nervous over the fact that despite the switch being off apparently it was still live when I used my tester. (I am going to re-affirm this however as I noticed after the fact that my tester lights up and is audible just by waving it in the air near there. Appears something in the attic is causing it to light up, more to come on that)

Either way things weren't as they should be to a novice and thus I promptly shut the project down.  I don't play around. I do however find it odd and would love to hear thoughts on how it works this way and why would it possibly have been wired this way? I thought black was hot and white was neutral so if nothing else it would be the black ones used?

So, the box in the ceiling has two pair coming into it.  Two black white pair.   One comes from the power source.  Think of that one as Line and Neutral.  The other one runs to the light switch wherever that is.  (  If you open the switch, you should find a black and white on the two screws.  )

Therefore, the two black wires are connected and beep your meter because the breaker is still on.   Keep them intact.   AND the white coming from the switch is connected to the black on the fan.  It SHOULD have a bit of black E tape to mark it as a 'switched hot'.  The white neutral is connected to the white wire on the fan.

How'my doin' so far?

The new fixture should be wired just like the old fixture.   Put the black where the black was, and the white where the white was.

Double check the box is secure enough to the house to hold the weight of the new fixture.


Ceiling lamp makes clicking sound after switching on lights? I turn it on, it right away makes a metalic click coming from ceiling. It then at times continues to make that same sound irregularly, even after turning off the lights. I can't sleep because of it. It stops after an hour.

Facts about the ceiling lamp:

it's not sitting flush on the ceiling, because an old metalic hook pokes out of the ceiling right where the lamp is. The   flat plate can be tipped from side to side because it's resting on the hook. The flat plate is screwed to ceiling but  not flush all the way because of the hook.
it's cheap Chinese lamp
the power cable feed to the switch outlet is only 1mm size, but the cable going to the ceiling is bigger.
3 ikea led lights (600lm each)

I don't like to hear that you have a ticking sound, possible heat expansion.  It is clearly not installed properly with old support eye still in place.  I recommend a complete proper redo of hanging of the fixture.  Make sure all connections are clean and tight. Get all obstructions out of the way.  And no pinched wires.


How can I prevent the mantel above a gas fireplace from getting hot? When I moved into this house, the unvented gas fireplace had no mantel or hood. It worked OK, although I thought the tile above the fireplace (and the sheetrock behind it) got rather hot. When I burned it for long periods, I would take the picture we have hanging above it down. A couple of years ago I bought a wood mantel, painted it white and hung it above the fireplace. Now the mantel gets hot. I doubt it would burst into flames, but its too hot to touch and would probably peel the paint off if left on too long.

I figured I needed a fireplace hood. Off to ebay and went and bought a hood. It sticks out 4.5 inches. I found a bargain on a brass one for $30 and thought it looked fine but my wife informed me it was ugly and looked like something from the 70's. Once again, I learned I have no taste.

Turns out the hood didn't help much, the tile above the fireplace and the mantel still gets hot. Not only that, it blocks some vents at the top of the fireplace which the instructions say is a no-no.

It appeared to me the heat needs to be directed up and away. I had some aluminum flashing laying around so I made a prototype shield. My idea was just to test it and if it works make one out of sheet metal as soon as I find a shop with a sheer and a brake. The good news is that it works great. The bad news is that its ugly.

Ok, the questions:

Has anyone else had an experience with the mantel getting so hot?
Has anyone seen a mantel heat shield like this I can buy?
If I stick with the homemade route - any ideas on how I can make it look better. (I do plan to paint it black and maybe cut it back some)
Any other creative ideas of what i can do for this problem? Maybe put a shield directly under the mantel?

Try putting a ceiling fan in the room to help circulate the air.


How can we measure the air quality index of our room? My house is situated near a construction site and dust, particulates, etc gather in really quickly. My room is currently set up such that there are two different air filters running continuously around-the-clock.

The Air Quality Index is a number which indicates how healthy or unhealthy the air is. For example, 0 - 50 is considered pretty good, whereas 151 - 200 is considered unhealthy, and 301 - 500 is considered hazardous.

Is there a way for us to measure the Air Quality Index of our room?

Depending on you local codes and the type of work being done, the construction contractor might be required to monitor her project's environmental impact.
As already stated, testing equipment can be expensive to purchase for private use, but Code Enforcement or the contractor might be able to help you out with a loaner of some type, or even perform an IAC test for you.
Great question.  Please let us know how it turns out.


How is telephone distributed in a home? I know in modern commercial buildings, "phone" jacks are wired like data with CAT5e (or higher) cabling to a patch panel on a 19" rack.  How does it work in small home with POTS?

Traditionally in the US, residential POTS was daisy-chained via 4-wire copper cable with drops at junction boxes or sockets. Only 2 wires (red/green) were used, with 2 spares (yellow/black). All the phones were in parallel, which caused potential problems with inadequate ringer current from the central office. The easy solution was to disconnect the ringers of extension phones.


Should I have paid attention to polarity when installing a new light fixture? I just installed a pull chain fixture in a closet.  The light works but I paid no attention to black wire to brass screw or white wire to silver.  Of course when I am tossing the box I see the instructions written on the interior.   Do I have to take it apart and check. Is it a potential problem?

Yes, you should fix it. If nothing else, if you crossed the wires, the threads of the socket would be hot, even with the switch off. This would give a good chance of shock when changing the bulb if you’re not careful.


Hardwood floor refinishing with polyurethane. Do I need to use any sort of base coat? What are the advantages? So we are refinishing an old oak hardwood floor, we have sanded it and are cleaning it currently before we apply a satin water-based polyurethane (with no stain).  Probably from varathane or minwax.

I was watching a couple of videos, and some people use some sort of base coat (I believe they are called sanding sealers).  Some say its for the purpose of leveling the floors and making the poly go on evenly, some say its to protect the floor from having the poly discolour it.  I'm not 100% sure what this accomplishes or whether or not it's necessary.  Information seems to be very mixed.

What does a sanding sealer do?  Should I put one on an oak floor for optimal results?  I'm not overly concerned about the extra effort.

My current plan is to do a test with and without in a closet, but I think having some more information from someone with experience in this area would help me make a more informed decision.

I would always suggest you avoid sanding sealers unless you have a specific reason to use one. Sanding sealers place a clear base coat between the wood and finish. But because the sealer is formulated to build fast and be easy to sand it can often be softer than the top coat which is problematic. The only advantage it would offer in your specific case is faster drying which might let you seal, sand & poly all in one day. Using a product you're unfamiliar with that may cause the finish to fail in order to save a day on a project is a terrible idea.

To give you a better idea what sealers (sander or otherwise are for) here's a non-comprehensive list of uses:

Lacquer finishes are sprayed on in a lot of thin coats. For woods with large pores that absorb a lot of lacquer sealing them can save time because it's faster to seal and sand than it is to shoot three extra coats before the finish begins to build.
Pine knots are infamous for leaking resins that cause trouble with finishes. The Knotty Pine movement is probably far enough in the past that it's not a big issue today, but it may come back. Teak and other oily exotics are in a similar category.
You can dye wood if you want a funky color and the grain showing. I bet you can guess what happens if you apply a water base topcoat over a water soluble dye. The problem is best avoided by not using a water soluble dye in the first place, but sealing is an option.
Tobacco smoke. In contrast to most finishes, sealers block odors. Animals and exotic cuisine odors can also fit in this category.
Nothing ruins furniture quite like silicone furniture polishes. Once absorbed by the wood the silicone ruins refinishing efforts. Rather than risk fish-eye most refinishers will seal everything after stripping.

In general you can do everything a sanding sealer can do with a clear topcoat. You can raise the grain with the sealer and sand it off, or you can sand the base coat. Sanding sealers also get suggested under pore fillers, but you can almost always forgo filling the pores in favor of letting the clear topcoat do it.

The one exception that I can think of offhand are faux finishes, where you want to pass one wood off as another.


Class C (20mA trip rating) GFCI receptacle/breaker? I have an electric radiant heat system under tile in a basement bathroom. Nuheat thermostat with built-in GFCI, dedicated 20 amp circuit. Ever since I purchased the home the system trips the GFCI whenever it's energized. Turns out one mat has a little problem but it was hard to find. A regular Fluke DMM won't even show any continuity between either the hot to the mat and ground or the neutral to the mat and ground but a megger (at 500 volts) tells me there's about 50 kilohms resistance between either lead and earth. That works out to 2.5 mA which shouldn't actually be quite enough to trip the 5mA GFCI built into the thermostat. When I test current on the hot side versus current on the neutral side of the mat while it's "hardwired" just for troubleshooting purposes I see up to 15mA difference in current going in from the line and coming back out on neutral.
I know what the right way to fix it is: rip up the entire floor and replace the mat(s). But I don't want to do that. I want install a floor thermostat without a GFCI built in and protect the circuit with a 20mA GFCI breaker or simply install a 20mA (class C?) GFCI receptacle before the thermostat to protect everything (I have a spot to easily install a receptacle.)
Problem is, I can't find a GFCI receptacle that trips at 20mA. Are there any Eaton/Cutler Hammer GFCI breakers that have a 20mA trip rating or an adjustable trip setting?
Thanks for reading.

The reason you can't find it as a receptacle is that there is no legal use for them in North America. Class C GFCIs can only be used where there is a reliable grounding connection, but that precludes their use where you want to plug something into a receptacle, because there is no way to ensure you are not plugging in a 2 wire device.

What you might be able to do is to put a Class C GFCI breaker on that circuit and hard wire the heating mat. But that is assuming 1) there is nothing else on that same circuit and 2) the heating mat is 3 wire, not 2 wire. If it's only 2 wire you cannot use a Class C GFCI.