Toilet sits directly over sewer return -- what sort of venting?

There are those that still maintain that a toilet needs a vent.
Take a look at this question here for one such opinion: Do I need to add a vent when moving a toilet drain across the bathroom?
However, the IRC has an exception for toilets (water closets).
From the 2009 International Residential Building Code

SECTION P3105 FIXTURE VENTS
P3105.1 Distance of trap from vent. Each fixture trap shall have a protecting vent located so that the slope and the developed length in the fixture drain from the trap weir to the vent fitting are within the requirements set forth in Table P3105.1.
Exception: The developed length of the fixture drain from the trap weir to the vent fitting for self-siphoning fixtures, such as water closets, shall not be limited.

So, the IRC is basically saying with a toilet (WC) you can run as far as you need to horizontally to get to the nearest stack. It would seem then that you could make a new stack and drop into the sewer line using a wye and an eighth. If all the rest of your plumbing is properly vented you should not have any issues.
Now, if you are making a powder room you will have a sink in the room also that needs to be drained and that definitely needs to be vented properly. (up to the attic and tie into the rest of the vent system) And with that sink drain line you could wet vent the toilet line up to the dry portion of the vent.
Good luck!


Can I feed a sub-panel from a sub-panel?

Yes, you can. The systematic computer programmer in me even thinks it's a good idea, allowing a "star" topology for electrical distribution.

You will need 4 wires, as others have mentioned.
Keep the ground and neutral separate in the subpanels. The only place they should be bonded is in the main panel.
You will need ground rods at the new location. Yes, it's redundant, but it's still required.
The wire feeding the new subpanel must be protected from overcurrent by an appropriately-sized breaker. It can be at either end - in the old subpanel or in the new subpanel - or at both ends. It's up to you, but if only using one, I slightly prefer the upstream location, so that I can easily kill power to the feeder wire. If using both, 1 must be sized for the conductor, and the other can be that size or larger -- convenient if you buy a panel with a 100A breaker preinstalled.
While there are wires rated for direct burial, it's good that you're planning to use conduit. Oversize the conduit for ease of pulling wires, and minimize bends. While you have the trench open, run a second conduit for future expansion (ethernet? gas? macerator?). May as well run a water line, too, so you can have a sink.
Most electric kitchen stoves are installed on 240V/50A circuits. If you're installing something like that, then I suggest a 60A subpanel. That gives you plenty of headroom to install lighting, a small point-of-use electric hot water heater, and some convenience receptacles. Those will come in handy when doing maintenance in the area.
Aluminum wire is usually much cheaper than copper, but harder to work with. It's stiffer. You must use 1 size larger than with copper. The ends must be protected from corrosion with anitoxidant goop. The lugs must be torqued correctly. Some people think you should retorque the lugs on some schedule. Last time I bought wire, I wanted 8ga copper, but 2ga aluminum was 1/2 the price, so going with Al was worth it.


I would use a tool called a "superbar" (sometimes called a pry bar). It looks like a crowbar, but is smaller and flatter

Place some wood on the pry part and use it to help push the board back into place.


Where's the C terminal on my boiler control?

Unfortunately, the Aquastat you're using does not expose a C terminal. The transformer is likely soldered directly to the board; so unless you're good with a solder gun, you're going to have to buy a different thermostat.
The red wire attached to the T terminal, should be connected to the R terminal of the thermostat. The white wire attached to the T terminal, should be connected to the W terminal of the thermostat. When the thermostat calls for heat, it will connect the R terminal to the W terminal. This will cause the coil to pull a switch closed (relay), which tells the boiler that the thermostat is cold.
If you're not afraid to potentially break things, and you really want to try to get the new thermostat working. You could try to add your own C wire. You'll simply have to connect the new C wire, to the other lead of the secondary coil of the transformer.

Left image shows original wiring. Right image shows where the C terminal should be added.
WARNING:
Modifying the wiring of the Aquastat will likely void the warranty, and could potentially damage the equipment. Proceed at your own risk.


What is the proper way to join two beams on a post?

Typically you would have the beam sit on top of the posts and use a post tie like this one:


How to identify make/model of a wardrobe?

Ikea usually has very distinctive structure, and usually "Ikea" stamped somewhere.  I don't have much experience with Jysk or Mio, but as far as I remember their furniture is more of the generic type.

BUT even for Ikea this is not that simple, they don't sell single shelves and their systems tend to slightly change over time.

Hangers are simple enough, you could probably find something generic in Krauta or bauhaus. Shelves are a little more challenging but you can always use generic shelf brackets and cut a piece of wood in with same color and thickness.


Why do builders say that wet concrete/mortar is not as strong?

My only guess is that a watery mix will have the layers settle in
  their different sedimentary layers with the fine cement settling to
  the bottom...

One reason is that the aggregate can settle to the bottom much too easily, yes. This is called segregation and results in non-cohesiveness of concrete.
Another reason too much water is bad is that it can result in porous concrete, especially at the surface.

  "Concrete that is poured too wet will be weak regardless of how it is
  cured. Not all of the water that is added to the concrete mix is
  necessary for the hydration process. In fact, the amount of water
  required to completely hydrate the cement is only about one half to
  two thirds of what is usually added at the batch plant or on the job
  site. The rest is added strictly to make the mix more workable. Adding
  too much water, however, might save work during placement, but it will
  also result in very weak, porous concrete, even with proper curing." - source

Excerpt from a good article (read the whole article) describing this problem in good detail:

  "When there is too much water in the concrete, there is greater
  shrinkage with the possibility for more cracks and reduced compressive
  strength. As a general rule, every additional inch of slump decreases
  strength by approximately 500 psi. So for example, if you ordered
  5-inch slump concrete and received 7½ inches, a mix designed to be
  4000 psi would end up being 2500 psi. This represents a serious loss
  in strength, especially if you were placing exterior concrete in a
  freeze/thaw climate where the standard requirement is 4000 psi for
  proper durability." - source

This is often the reason for the slump tests that are done on most large projects. It tests the workability, but also indirectly tests if there is too much water.


Extra insulation for panes of aging windows

I've used the plastic window stuff before (literally just finished putting up some a few minutes ago) and it works quite well. Another option to look into is storm windows, they go a long way to helping keep a house warmer.  You can purchase storm windows in standard sizes at the usual hardware stores, or order custom fit ones if they don't have the ones you need.

There are also weatherstripping products you can get for your windows.  Wired currently has a decent overview of what your options are.


Typically, an aluminum or galvanized "z flashing" as you called it, would be installed under the siding, over the top of the ledger and down the upper lip a little. Decking is installed on top of this flashing.
(Diagram not to scale)

Done this way there is no need for any of the other products you mentioned unless you have moisture or insect concerns from below the ledger.
I would not use vinyl or copper tape for this, any cracks will prevent it from working properly so it needs to be very durable.


how to wire a 2 way switches with 2 pendants

It sounds like you want a pretty straightforward lighting circuit with a 3-way switch at each end of the hallway controlling the lights. To do this, you must have 3 conductors running between the switches. The typical way to do this is to run a 3-conductor cable, such as 14/3 NM or MC cable. You can't legally string a lone wire through the attic, so pull new cable if you need it.

This answer might be helpful, and it references others.


best way to secure metal strip between tiles and wooden floor?

That looks like a snap in style once they pull out a few times the Chanel may need to be squeezed together if the raised section on the back of the trim is still in tact. If the raised section has broken off 3 small flat head screws can be added by predrilling and counter sinking the holes (predrill in place to punch a hole in the channel ). This would be how I would repair it to stay in place.


It really matters how wires are grouped into cables or conduits.

One black is supply.  It is always-hot.   It is probably grouped black-white-copper.

Another black is simply passing power through to something else.  You may notice with the switch removed, something else doesn't work.   That's where that black goes.   It is probably grouped black-white-copper.

The remaining black, and the red, are 3-way messengers going to the other 3-way switch.  They work together as a matched set, and they are interchangeable.  Think of them as a matched set.   They will be grouped black-red-white-copper.

Your 3-way switch will have a ground screw.  It will also have 3 other screws, with one an odd color compared to the others.  The two same-color screws are the messengers.

That leaves the "always hot" black wire, and the black wire going to the "something else".  Those need to be joined to each other, and connected to the remaining screw on the switch.


How to estimate the right size furnace for my house

You cannot estimate a furnace by the size of your house.   That is just a factor in the equation, and it is not 80% of the equation or even half.
So first when you have the size of your house you should not calculate square feet, it should be cubic feet.   A house with 8 foot ceilings is considerably smaller than ones with 10-12 feet ceilings.   If a furnace tech quotes you on the square feet in your house - wow get a new tech.
Also you need to factor in the cubic area of the unfinished areas that are connected - your basement, useable attic space, an enclosed patio.
Then you have to guestimate - there are services that will get this done for you accurately - how efficient you are insulating your house.   A house that is well insulated may require half the heating of a house with little to no insulation and bad windows/doors.
The last thing is the one-offs.   Are your duct runs longer than average?   Do your ducts travel in the attic or underneath foundation?   Do you have more ducts than normal for a house of your size?
You are rating the entire house system plus size.   There is no easy equation.   An old exterior door with gaps in the middle of the house could cause 10% heat loss.   The problem is if you rate too low your house will never be warm and you will stress the furnace and blower and it won't last as long.   Yes rating too high and you lose a little money in efficiency.   But really you always have to be a little over when estimating or willing to spend a lot of money insulating and replacing windows/doors.


How can I grind and smooth a concrete table top?

You can always use a masonry grinding wheel and a level, but be warned, there will be a LOT of dust! You'll want to seal off the room from the rest of the house, open the windows, put fans in the windows, wear goggles and a respirator. They sell shrouds that you can hook up a shop vac to the grinder to get a good bit of the dust, but it's still bad. And at that point, it might take you 2 to 4 hours. I leveled some high spots on my basement floor and man, what a time waster! You may be happier if you rented something bigger than a grinder, or used something like below - the bonus being, if you used aggregate, it'll shine through after grinding.

You could also rig up a sled if you would like, where you attach something flat to the back of your grinder and then run it along something flat and level independent of the table surface, like below. Unfortunately, I don't think they make diamond cup bits for routers, but you might be able to use a diamond hole saw with a 1/4" shank if you want to use a router/sled method.


What could be causing my underground well house to flood?

If you have metal pipes, and the high utility bill would seem to indicate that your well-house filled due to pumping itself full, digging down to fix it would appear to be a logical approach - though I don't know that I'd be "looking for leaks" as much as "having dug the expensive hole, replacing all the pipes while the hole is open." As mentioned in my comment, I'd use polyethylene water pipe rather than any sort of metal in ground contact. The higher pressure grades are thicker wall, which makes them more durable in general, even if your water pressure is not nearly so high.

This part does not really have anything to do with fixing your leak: Having just replaced it, you won't want to change this part, but I'd also take a long look at not having any "electrical control box" in an underground wellhouse that's prone to flooding. That, however, typically requires changing the pump as well (depending on exactly what it is - if it's a "3-wire pump" and the control box has a capacitor/starter for it, you have to change to a "2-wire pump" - if it's just a pressure switch, you may already have a two-wire pump, and relocating the pressure switch might be all that's needed), and 2 .vs. 3 wire pumps seem to be a philosophical divide among well people. It's also more money on top of an expensive hole, and you may be fine if the expensive hole and pipe replacement means the thing does not fill with water again.


I'm not sure what's available in your area, but heavy duty construction adhesive is ideal for this. I've resolved many annoying squeaks and pops by running beads along all accessible joints, then fingering it out to spread it and press it into the gaps. (Use disposable gloves or a tool to prevent a lasting bond to skin.) Over a few days it hardens nicely and bonds extremely well.

In addition, add construction screws where you can to tighten joints and prevent slippage of existing fasteners.


What do you want to connect in parallel?

The Live and Neutral?

That is the correct way to do it.

Each 'L','N' must be connected to each next 'L','N' in parallel from your main power source. Also it is a good idea to earth all your florescent lights to a earth leakage breaker or something similar as they can sometimes develop high voltage leaks and cause undesired effects..(smoke/fire,etc)

Do not exceed by 1200Watts on a 5AMP Breaker in 240Volts

You cannot connect the florescent tubes in parallel or in fact any other way than the ballast was designed to handle it. You can get double/triple ballasts too and the internal wiring can get somewhat 'spaghetti' like.

Each tube needs to be handled by 1 ballast as it 'starts' the tube then 'sustains' the voltage for it.

There are new electronic ballasts that do not require starter caps and 'start' the tubes quicker with less stress extending the life of the tube up to 25%.


If I apply for an electrical permit, will an inspector call me out for previous unpermitted work?

This, of course, depends on the inspector. They will obviously inspect the work you're doing but they will be looking in your panel and can check anything that looks suspicious. I doubt they'd make you tear out anything unless it was a complete disaster and dangerous. They could make you repair previously done work if it was done incorrectly. As far as ripping all the old work out, that usually doesn't have to be done unless there's a total renovation in an area and you have really old wiring, knob and tube.


How should I fix an electric shower pull cord that doesn't work anymore?

I've never seen an electric shower (looks to be a European thing?) but based on the diagram in that article you've got electrical contacts near moisture. Corrosion is quite likely and would cause intermittent problems like you describe. Turn off all power to the device then open it and check for "crud" on any of the electrical terminals. a fine brass-bristle brush can help remove it, or even a Scotch-Brite scrubbing pad.


How can I fix a stripped hole in an aluminum piece?

Depends on the size of the screw and how much material you have to work with. If this is a clamp bolt, cheap tripods use screws going directly into the casting. Quality units either use a captured nut, Nyloc nut and eccentric toggle or a tee-head bolt with threaded knob.

If this is a plate with a fair amount of metal surrounding the hole and it's deep enough, I would get a Heli-Coil kit. With this kit, you drill the hole oversize with the supplied drill, use the supplied tap and then the tool to install the helical insert.

Another thread repair is Keensert which, if you have yet more metal because it's a larger device, a locking insert that doesn't require delicate use of Red Loctite to keep it in place.

All the above probably are not recommended in the case that the threaded hole is in a casting that doesn't have spare metal, so the previous recommendations of drilling oversize and tapping for a larger bolt might be the best. Which might not be a solution if the threads are common photography standard attachments between devices.


Thinset isn't necessary but works. Masonry mortar works just fine too but I'm a long time user of Structolite to set shower bases and yes it's necessary for a strong base. It gives you a solid feel to the pan. If you were on level plywood many do without but it doesn't have the same solid feel. I personally like to drill holes in the flange and use stainless screws to attach to at least two studs.


How can I disable a turn button lock without destroying it?

I've put tape over the turn-knob, but that solution is imperfect.   Get a different doorknob set that omits that "feature", and throw this lockset in a gallon Ziploc for refitting at sale time.

Since lock quality is not a factor, a $10 passage set should suffice.


What should I do after mistakenly using moldy paint on drywall?

Mold need two things to create spores, water and air.  You probably killed any active mold when you mixed it in the bucket.  However, don't fear. Once that coat is dry, recoat with fresh paint. It will seal over the original coat and any surviving  mold should be encased and die. I think you will be fine, just repaint.


Are both legs of a home's power supply equally used?

If you look at a service panel without any breakers in it, it will look something like this.

Notice the thick metal plates running vertically, those are your hot bus bars. One is L1 (A), and one is L2 (B). They are each at 120V potential to ground/neutral, and 240V potential to each other (So don't frigin' touch them!).
When you add breakers, they will make contact with the hot bus bars using the tabs that protrude between the bars.

You'll notice on the cover of the panel that each slot is numbered, with odd on one side and even on the other.  So for a 20 breaker panel you'll have.
1    A    2
3    B    4
5    A    6
7    B    8
9    A    10
11   B    12
13   A    14
15   B    16
17   A    18
19   B    20

So 1 & 2 will be on leg A, 3 & 4 on leg B, and so on down the panel.
What types of things are fed by each breaker will determine which leg is used more.  For example. If breaker 1 feeds the lights in your living room, and breaker 3 feeds your bedroom lights. If you turn on the living room lights and turn off the bedroom lights, leg A will be used more than leg B.
For 240V circuits, you'll use a double pole breaker that spans two slots on the same side (eg. 2 & 4). This means it will have a hot from each leg, and will use each leg equally.
So the short answer is... It depends.
More Information
While we're on the topic, lets tackle some misnomers about phase in this type of system. While this is sometimes incorrectly called Two-Phase, it is in fact a 3-wire, single-phase, mid-point neutral system (Sometimes called Split-Phase).
As you may or may not know, we are dealing with Alternating Current here. So viewed with an Oscilloscope, we'll see a Sine Wave like this.

However, since we can measure this system at multiple locations, the waves will look slightly different depending on where we measure. This is where the misconception that this is a two-phase system comes from. Lets slow things down, and look at what is happening in the system as the current alternates.

At this point current is flowing in a positive direction on L1, and a negative direction on L2. Because of this if we measure between different points, this is what we'll see.
L1 -> N = +120V
L2 -> N = -120V
L1 -> L2 = +240V
Now as the current swings back the other way, we'll start to see the sine wave appear.

If we take the same readings again, we'll find things have changed.
L1 -> N = -120V
L2 -> N = +120V
L1 -> L2 = -240V
As you can see, it really is a single phase. Things just get a little confused when measuring from Line to Neutral. A true Two-Phase system, would use 4 wires and the phases would be shifted 90°.
In this type of system the two lines are not referred to as "phases", instead they are called "Legs".


What is this dark oily liquid leaking from the drain pipe under my kitchen sink?

My first guess?

Food grease/water mix where the water has evaporated..

When hot water runs thru the sink the metal will expand and the cracked fitting will allow leakage.

To test:  Put pan under fitting.  Run hot water for 5 minutes.  Watch for drips.


Want to change a half switched outlet to constant power

One of the sets of hot/neutral wires are switched (probably red/white) and one is unswitched (probably black/white).  You only want one set connected to your new outlet. If you connect both, you'll short them together. Best case, your whole switched circuit will become unswitched. Worst case, you'll connect together opposite legs of your 240v feed and blow breakers or start a fire!

Try connecting the black and corresponding white to the new outlet and cap the other two wires with wire nuts. If the whole outlet ends up switched, exchanged the connected wires with the capped wires.

Edit: as Michael Karas points out (thanks), check the side of the old outlet where the white wires were connected. If that tab was not broken, go ahead and connect both white wires. The outlet may have been used as a jumper to extend the neutral to other outlets/loads. You still never want to connect both the red and black wires.


Moving Romex (or other NMB cable) to under the subfloor?

Unless there is something on the underside to prevent this, it would APPEAR that you should be able to drop the wires under the floor where they come down from above and turn - of course, that would require freeing up the wires so they can be re-pulled, or a mess of a junction box.

And there's the fact that this was not what was done to make me question if there is something blocking from below, or if it was just lazy weirdness when removing a wall that lead to this "interesting" approach.


Why won't hot water come out after turning the water main back on?

Since you have no water coming out or just a drip a large chunk of rust or scale could have broken loose from your main and plugged the water heater. I would close and open the valve to the water heater to see if this crumbles or breaks up the debris. If that works it really is time to flush the water heater from the bottom drain. A hose connected to the bottom drain and taken outside or to a close sink or toilet makes this job clean and easy. If you have valves on both the inlet and outlet cycle both. If this works on the outlet side be prepared to clean the faucet aerators. If you get water running and hot water again it is also time to check the Anode rod. Anodes reduce corrosion inside the water heater and are eaten away (Another source of gunk in the bottom of the tank). Good Luck.


How to properly wire a ceiling light fixture?

The power (from the breaker) is likely at the light fixture.  When you hook black to black and white to white, the light is powered directly from the breaker. In this configuration, when you flip the switch on you create a short through the switch.

What you need to do is hook it up like this.

Notice the white wire that runs between the switch and the light has a black stripe on it (in above image), that lets anybody that works on this light in the future know that the wire is switched. You can mark the wire using a bit of electrical tape, or a marker.

Figuring out which wires come from the breaker, and which go to the switch will require some tools.  First Turn off the breaker, and verify the power is off using a non-contact voltage tester.  Now pick one set of wires to work with first (one black and one white from the same cable). Turn the switch to the on position, and use a multimeter to check continuity between the two wires. If the wires are connected (low resistance), these are the switched wires. If not (infinite resistance), check the other set of wires. If neither pair pass the test, contact an electrician.

If at any time you don't feel comfortable doing this work, or you don't have the proper tools to complete the task. Contact a local licensed electrician.


How about a door edge guard? These door edge guards are constructed of solid brass and come in a variety of different  finishes. These door edge guards are used to protect the door trim from being dented or damaged by swing bar type locking hardware. They feature an adhesive backing that provides for a quick and easy install, together with the assurance of a strong and permanent hold. These types of edge guards are designed for use in both residential and commercial applications.

You can get them at Walmart or Amazon.


Basic Circuit Breaker trips inconsistently, persistently

There are a few possibilities, if this is a standard breaker.  If it is AFCI or GFCI, there are a few other things to check, but you didn't mention that.

There is a high-current draw on the breaker that you are not aware of.  When the breaker trips, you can check the temperature of it with a non-contact thermometer.  If it is warmer than the breakers around it, that would indicate a high current load.  The internal heat is one thing that causes a breaker to trip.  You can also check the load with a clamp meter after removing the cover for the panel (you might not be comfortable with that).
The breaker is bad.  This happens, but its not very frequent.  Replacing it requires removing the cover of your electric panel (again,  you may or may not be comfortable with that).  It's a simple a cheap item to replace, so if there isn't a high load and its still tripping, this could be a good next step.
There is a bad connection to an outlet or light that shorts out periodically.  This can be the hardest to find, so that's why I suggested replacing the breaker to rule it out before hunting for this one.  The only way I know of finding this is to inspect every connection downstream from the breaker to find a loose or charred connection.  Any outlet that is loose in the wall or doesn't feel right when plugging something in would be suspect.


Will 1x4's and 1x6's be enough for an aquarium stand?

Use 2x material... it's probably cheaper, stronger, and gives you more surface to screw into. (edit: this was based on the original question -- 'use 1x or 2x material?')

1/2" ply would probably be fine, but I'd suggest you upgrade to at least 5/8" ply (or whatever the horrible version of that is in the box stores -- 19/32"?!?) to skin the exterior. Construction adhesive would also be a recommended upgrade. Screws every foot or so.

With a plywood skin on 4 sides and the top, lateral pressure won't be a problem.

Thicker ply and 2x materials should make this adequate for 1000#, but only you can be the judge. (Maybe we need a bounty to decide what the best testing methodology is... I vote that you take it to a big box store and start loading bags of concrete on it.)

For the top, if you aren't sure that your weight will be bearing on the wood, 5/8" ply wouldn't hurt, either. One cross-brace would probably be all you need to keep the top from sagging and help keep the entire unit from wobbling.

Design-wise, you can make your life somewhat easier by double-thicknessing the legs and lapping them. (Can sketch if needed.) The 2x6 at the bottom could be replaced by a 2x4. (edit: this comment was based on an earlier sketch...)

Edit: let's see if I can add a sketch...

(sigh. after 2 attempts, I can't get it to rotate properly. Sorry.)


What are the elements of this apartment map?

Yes, They are proposed appliances. not the same symbols we use here in the USA however. the arrow at the bottom is an egress window.


Is there a good rule of thumb for how many lights you need in a room?

You need to consider many factors.

Beam angle: spot (narrow) vs flood (wide), and everything in between

The wider the angle, the farther apart the spacing can be without creating dark spots on the wall

Direct vs indirect light: is the light facing the wall, so the room is actually lit by light reflecting off the wall, or are the lights directly lighting the floor/whatever it is in the room?

Reflecting off the wall will make less lights seem brighter (vs direct lighting), and creates a softer light (not many shadows, light coming from all directions)

Wall color: especially if you're mostly using indirect lighting from the wall, the color will dictate how much light is reflected

Light colors (eg, white) will reflect the most, while dark colors (black/gray) will reflect less.
Strong/vibrant hues (eg, red, blue) will also cause the room to appear that color. Eg, if you have red walls, and all your lighting is indirect from reflecting off the walls, the room will look like it's lit with red lights. If you use direct lighting in the same room, objects/people in the room will have closer to normal colors (you'll still have some element of red, of course)

Heat: depending on the types of bulbs, more heat will be generated, which should be a factor to consider. A room with a dozen halogen bulbs, for example, will be noticeably hotter while the lights are on full. CFLs and LEDs generate much less heat, but have other drawbacks.
Dimming: If the lights are dimmable, and you plan on having them dimmed a lot of the time, you may need more fixtures to generate an even look.
Electrical load: Code says you should design to use 80% of a circuit's capacity. If you have a dedicated 15A, 120V circuit (breaker) for these lights, you can use up to 1440 watts total. This means if you have 100W bulbs, you can only have up to 14 of them.

If the circuit is shared with other lighting/outlets, be aware that subtracts from the power you have available.
In Canada (at least) there is a limit of 12 outlets per circuit. I'm not sure if that applies to light fixtures or not though, maybe someone else can weigh in?


Yes, every "standard" (non UPS, non "smart") power strip that you buy, will stop that "vampire draw" when it is switched off.  It's just as good as unplugging the appliance and one reason why power-strips are made in the first place.


What should the input pressure be for a hydronic system?

I doubt that the 50 PSI pressure reducing valve is for boiler service. It is most likely to be used as a domestic water reducing valve. Boiler PRV's are all pre set to 12PSIG. That said, the boiler pressure should have a cold fill pressure setting is high enough to hold a column of water up to the top of the highest radiator. You can calculate that pressure by multiplying the height in feet from from the boiler pressure gauge to the highest radiator and multiplying the dimension in feet by .433. So for example, if the height of the highest rad is 25 feet then (25 X .433 = 10.825) the minimum boiler pressure setting. Then you add a lb or two for the minimum setting. Round up the 10.825 to 11 and add 2 psi for a cold setting of 13PSI.
Most residential boilers are rated at a maximum working pressure of 30 PSIG. Then the relief valve, sometimes called a safety valve, is set for the 30 PSI maximum .  Increasing the pressure above the cold fill setting does not affect the boilers efficiency. The pressure is just to make sure that the water level is held up to the highest radiator that is all it does.
Now, I am not trying to insult you but your question/explanation makes almost no sense in regard to boiler operation with over pressure, venting, cooling down, etc. Before you go any further, look up on U tube or other forum for how a hot water system operates.


Will I have problems from waiting to grout patio tiles?

Shouldn't be a problem. Clean out the gap between tiles with a garden hose (or pressure washer if you have stubborn "dirt" like bird poop), then blow out with a air gun and compressor.
You only have to wait til it's dry after a rain (or washing out) before commencing to grout.


Is the huge white metal grille on a ceiling called a "cassette AC". Is it supposed to be noisy?

That's the return air grille, where the AC's air handler sucks up air to cool that it pushes through the ceiling registers in the other rooms. Central return systems are inherently noisy, but good duct design can alleviate this to a certain extent as can using a smaller blower motor if the ductwork was done well enough that the reduced airflow speed doesn't result in worse air delivery.

Your bigger problem is the fact that your air conditioner is in the attic, where it will get to be like 140 degrees. I bet every time it kicks on, all the rooms get blasted with a slug of hot air for a few seconds, right?


Shower/Tub caulk cracking on new bathroom shower

Latex is another common caulking material. Sounds like you're looking for something like this:

http://www.homedepot.com/p/Custom-Building-Products-Polyblend-09-Natural-Gray-10-5-oz-Sanded-Ceramic-Tile-Caulk-PC0910S/100678060


Discovered 10/2 wired 3-prong receptacle for dryer. Is it ok to leave as is?

Replace it with a homerun of 10/3 and a NEMA 14-30.  It's the only way to be sure.

The original installer was a massive cheapskate with no understanding of the NEC -- even if the install was old enough to be grandfathered in under NEC 250.140 and friends, it still was a violation at the time of install as using an uninsulated wire for the neutral (grounded conductor) is only allowed when using type SE cable, not type NM as the original installer did:

  50.140 Frames of Ranges and Clothes Dryers. Frames
  of electric ranges, wall-mounted ovens, counter-mounted
  cooking units, clothes dryers, and outlet or junction boxes
  that are part of the circuit for these appliances shall be
  connected to the equipment grounding conductor in the
  manner specified by 250.134 or 250.138.

  Exception: For existing branch-circuit installations only, where an equipment grounding conductor is not present in
  the outlet or junction box, the frames of electric ranges,
  wall-mounted ovens, counter-mounted cooking units,
  clothes dryers, and outlet or junction boxes that are part of
  the circuit for these appliances shall be permitted to be
  connected to the grounded circuit conductor if all the following conditions are met.

  (1) The supply circuit is 120/240-volt, single-phase, 3-wire;
  or 208Y/120-volt derived from a 3-phase, 4-wire, wye-connected system.

  (2) The grounded conductor is not smaller than 10 AWG
  copper or 8 AWG aluminum.

  (3) The grounded conductor is insulated, or the grounded
  conductor is uninsulated and part of a Type SE service-entrance cable and the branch circuit originates at the
  service equipment.

  (4) Grounding contacts of receptacles furnished as part of
  the equipment are bonded to the equipment.

So, replace this abomination with a fresh homerun of 10/3 and a NEMA 14-30 receptacle -- you'll have to change the power cord on your dryer to a four-prong one, but that's a small price to pay for never having to worry about getting bit by your dryer again.


How can I run wiring around an inside corner?

If you are having issues with drilling the corner, realize that you can make the job significantly more possible with an ordinary drill if you don't try to hold it level - shift the wire up or down a few inches as well as taking it around the corner, and the hole becomes much easier to drill.

As for your question about the approach using conduit, that's going to depend on the LAHJ (local authority having jurisdiction) a.k.a. "the building inspector", if you are subject to inspection. Generally better to ask them first, than to try and convince them that the internet said X would be OK...what is acceptable in one local area may not be in another, and in some cases what's acceptable in the same area will vary with inspector (probably shouldn't, but often does, even so.)


Quikrete didn't absorb much water. What did I do wrong?

Bagged concrete dumped in hole dry can work but is not ideal. With a clay base the hole is like a pipe. Adding water to the top the mixture will absorb water a few inches down then create a seal. It may be possible to get the mixture wet by heavily soaking the area for a week or more. Moving the post may allow water to penetrate deeper at the cost of creating clumps around the post not the solid mass you want. Winter rains and the higher ground water water level may help. If you would like to use your hammock next week pull the post clean out the hole knock the clumps off the wood and put the post back in the hole. Now there are 2 options. Mix the fresh bag's of quickcrete in a wheelbarrow and fill the hole or put some water in the hole add quickcrete , water more quickcrete water... You get the idea two much water will make it weak but stronger than the original no water in the hole mix.


How do I tape new drywall that is butted up against a textured wall?

Scraping then taping will work.  Re-blending the new and old textures invisibly is nearly impossible.

Consider replacing 3 to 4ft instead of 12" and adding a wainscot or just a chair rail and leave the bottom smooth.


If you have any small pieces of drywall up on the ceiling, I'd start by removing those to get back to as many full sheets as you can which should also minimize the cuts you need to make. As user41750 says, make sure you match the drywall thickness. The joints will only be staggered in one direction, along the 4' lengths where the drywall isn't tapered. You want those 4' long joints to meet on a joist or nailing surface.

The 8' spans will be perpendicular to the joists and be tapered. You can knock out the mud and tape from inside the taper of the existing drywall to get two tapered joints to align. If you don't have an existing tapered joint, then you'll want to cut away the taper to avoid a significant difference in height where you are mudding and taping later.

The mudding and taping is an art. There's a fair bit of advice on this site to help you there, but I wouldn't blame anyone for hiring out this part of the project. And from there, it's all about matching the finish. I'd personally prime and paint the entire ceiling, if not the walls too. This will help hide any division between the two spaces.


Dishwasher shows a drain problem - diagnosis

Since it thinks the filter is blocked, but you're not finding any blockages, I would think that the sensor that's responsible for telling the computer that nothing is flowing is failing.
A quick DuckDuckGo search for "BOSCH SHEM55W55N parts list" brought me to this site that has a parts diagram for the pump assembly. Scrolling through the parts list for the pump shows a sensor. Since you've been in there, make sure that's the area you're talking about, if that's not it, they have schematics for the whole machine, so you should be able to find the filter you're looking for and an associated sensor, if I've picked the wrong one.
At the current price of $30 USD, it's not the cheapest part to replace on a hunch, but it's certainly not the most expensive part, and definitely cheaper than replacing the whole thing.
No affiliation with or recommendation of the linked site - it was just one of the first options that looked good.


That appears to be Corian (or something similar).  You can find cleaning and repair guides on the DuPont website.  These counter tops are not horribly heat resistant (as you found out), and can discolor or even melt it enough heat is applied.

I've heard that letting baking soda sit on the stain for a while will remove some discolorations, but I've never tried it myself.  My guess is that you'll have to try to polish it out with a very mild abrasive and hope it didn't go too deep.  See the section in the linked page above for "Removing Fine Scratches".


Is it dangerous to request more power from a mains circuit than intended?

The main purpose of circuit breakers is to protect wires in the walls from overheating.  Even sprinkler systems cannot access wires in walls to put out the fire; the fire can become fully engaged.

You are messing up. You should not overload the circuit like that.

Your local government probably has provisioning standards for electrical supply.  For instance in the US, we must provision power for 125% of continuous loads + 100% of loads not continuous.  Many things such as a heater or EVSE are designated continuous loads even if they are not continuous.

So if I want to put a 1200VA water heater and an 800 VA garbage disposal on a circuit, I must provision 1200x1.25 + 800 = 2300 VA.  That just limbos under the 2400VA capacity of a 120V/20A circuit, so it is alright.

Stay within the provisioning limits of the circuit.  If you need more, either provision it or move the loads around physically to get them on different circuits.  This is often a blindside of Bitcoin miners who want to put 10,000VA of miner all in one room (never mind the cooling problem that creates!) Spread them around the house so they are all on different circuits!

Trip curves

Circuit breakers have a designed trip curve.  They will trip when current draw and time match the trip curve, with some tolerance.

This example (thanks Tester101) shows this breaker will:

at 2x rated current, trip between 9 and 35 seconds.
trip in 1 second with an overload between 4.5x and 8x.

These numbers vary due to manufacturing tolerances.  Note that the Square D does not vouch that it won't trip at 100% load; it only says it'll take at least 300 seconds to trip.

You should look up the trip curve for your breaker.  Its behavior should match this.


Do you need to oil the bushings in a doweling jig?

This is a good question for the woodworking site, but I would not oil the guide, the oil will stain the wood. Do use care while using the guide, use sharp drill bits that will not need to be forced to hard to drill. The more force you use the better the chance of angling the bit in the guide, wearing it out prematurely, and making the dowel go in holes that are not in line with each other. Brad point bits are preferred here. Purchase drill stops too, if you don't already have them...


are steel SIPs Structural like OSB SIPs

Yes. They are generally equivalent as they both do the same job, for the same reason other than they are using different materials, wood based materials vs metal based materials. You can temporarily remove the specific materials from your thinking and everything is about the same, including where support members are located, where and how things are attached, etc. This is all about materials. During the design of the materials, the steel SIPs are designed such that they generally mimic the wood based materials. In reality, the actual numbers are likely different but this is on a smaller scale / fine tuning level


Can I add copper wire led lights to existing 12V Landscape Light Transformer

If "some sort of an adapter" is a 5V voltage regulator which can accept 12V or more input, perhaps yes. If not, no, and more may be needed if either one is AC, not DC.

You may (quite probably) also overload the 12V adapter if it's matched to the current string of lights such that adding more load would exceed its capacity.

Simpler and safer to just run the 5V adapter to a plug.


How can I verify the integrity of smoke detector interconnect wires?

First I would check the wiring to the smoke detectors. You should have three wires, one white (neutral), black (hot) and another color usually red (the interconnect between the smoke detectors). Then I would verify that they are all pigtailed and are going to each individual smoke detectors. While I had them down I would also check the batteries and make sure they are charged. May just replace them to be sure. If everything checks out you should be able to get all of them to go of by pushing the test buttons. First the one you pushed the test button on then after a slight delay the others should start alarming.

If you test them and each one is sounding locally, then the interconnect is not connected between the detectors.

After you test them and one is not alarming, I would say it's probably bad and needs replacing.


Is it ever ok to wash a towel that has had mineral spirits on it?

There are 2 separate prongs to this problem.
Allowing flammable solvents into machines and sewer systems.
We don't want to wash towels that are contaminated with flammable solvents, because the vapors will wind up all sorts of places we don't want flammable solvents.  That includes:

Flushed down into the sewer pipe - sewer gas is bad enough!
In the mechanisms of the washing machine where it could attack plastic components and potentially start a fire.
Wafting through the dryer where it will make contact with hot heating elements or worse, gas burners!

Certain flammables will self-combust
That is because they have a "curing" behavior similar to epoxy or concrete - and like most cures, it is exothermic.  If that heat is sufficiently bottled up, it can rise to its own flash point and FWOOF!  About 1700 house fires a year are caused by this.  That generally relates to paints and stains.
However, I generally recommend developing the habit of handling all "oily" rags on the assumption that they will behave exothermically.  I spread them all over the shop for a week to dry out, or better, leave them out in the rain.


Why is there 4 inches of metal at on each side of this column?

The metal that you are detecting is probably the metal studs that are in each corner of the column. From the picture it looks like that column is also sheathed in drywall and so there may very well be a metal corner strip along each vertical edge as well. The metal studs width are typically going to be 3.5 inches. The drywall thickness from the adjoining sides is 0.5 inches and with the metal corner piece it adds up to the 4 inches that you are seeing.

As mentioned in comments this column is most likely a place where some part of the building infrastructure is located. It could be a structural beam, vertical routing space for water or gas piping or electrical wiring.

As to whether you can use conventional drywall anchors to mount light weight things to the living space side it would be best to be certain what is inside this thing before you go drilling holes in it. It could be OK but then again it could be something to be highly discouraged for a variety of reasons.


What product should we use to finish stair treads?

~20 years landlord experience, we learned to stop painting all the trim white and use poly. It looks nicer/more expensive and does not definitely need attention every time it's up for rent. Paint gets dirty, urethane just looks properly aged.

Whatever it is, if it's made out of lumber, stain and urethane it.


For 4x4 posts mounted on their butt end to a concrete surface it seems like a robust solution. One concern is that if you ever have any rotting and some of the wood ever needs replacing it will be rather difficult to remove these posts. If it is a solution that you would expect to get 5 to 10 years of average service life out of then the solution will work nicely.

One nice aspect of the described solution is that it lets the post sit right on the concrete without any visible fasteners. Any other type of post butt fastener is going to show some type of metal brackets that could detract from the aesthetic.


What are the specifics I should be looking for in a quote to replace my concrete steps?

I'm not a concrete expert by any measure, but here are a few questions I would have about the job.  I'm not looking for you to answer them here - they are just questions you should know the answer to and possibly should be a part of the quote.

Are you sure you want the same rails replaced in the new steps?  Won't they be damaged when removed and if so, who pays for new rails/posts? Are they also replacing that stone "slope" the rails are sticking out of?
Does the current stair design meet all building codes or will it have to be modified to meet code?  Check on rise/run measurements, landing requirements, ok to have rails on just one side, etc.
Do you require any building permits or inspections to get this completed?  Who pays for the permits?
Are they hauling off and disposing of the old material?  You may be able to shop for cheaper demolition since that is unskilled labor.
Do you want a time estimate in addition to pricing?


Sump is sealed for radon remediation and doesn't drain water. What can I do for water drainage?

Put a surface pump at the lowest portion of the basement? That should keep the flood down to an inch or so; not perfect but better.

(You could build up some sort of basin around the mechanicals so they have their own "sump" sitting on top of the slab... but Murphy's Law says that the next failure is going to be somewhere else in the system.)


Build the walls with a double top and double bottom plates. Span the splice between the sections with as much length of the plates as you can.

In my jurisdiction, wood in contact with cement has to be PT, so I'd use that for the bottom plate.

Get the bottom plate nailed/screwed/bolted down first, raise the wall sections onto it, brace those wall sections temporarily. Then bang your extra top plate into place and nail or screw it to the wall sections. Attach your top plate appropriately to whatever's above it.

ps, watch the height of the wall across its length... garage floors usually slope and ceilings are usually level...


Are these corner brackets that hard-to-find?

There is this one on Amazon:
https://smile.amazon.com/dp/B071W4VQPT
You are working with a 20x20 tile and these are 2.25" Roughly

These ones: https://smile.amazon.com/dp/B0195UGD38
They are much larger, though WAY more Expensive.

Though you will see those Brackets. You could use something like this on the Inside with some Galv Bolts or SS Screws to make it look nicer.
https://smile.amazon.com/dp/B07CWMSS79

I'd put two on each adjoining edge. so 2 in each corner and 2 on each side on the bottom.


9-12 months is a recommendation. The only way to check a filter accurately is with a dual port manometer

Amazon
Nobody is going to buy one of these just to check the filter. Visual and auditory cues are usually enough. If the pleats on the filter are starting to deform it's probably due for a change.
Also keep in mind that ceiling returns tend to pull in less dirt, thus increasing the life expectancy of your attic mounted filter.
All things considered I wouldn't be surprised if you get 3 - 4 years out of the filter. It's dependent on usage and you'll need to monitor it. But don't hesitate to leave a clean and functional filter in because it's old.


It sounds to me like you've got a two stage furnace.

Stage 1, low heat, just enough to maintain temperatures.  Won't produce warm air, just warm enough air - much more efficient than running full burn.

Stage 2, high heat, for when it's actually cold.  Produces WARM air intended to raise temps.  Less efficient than stage 1, but gets the house warm.  Stage 1 follows.

The alternative is a 1 stage furnace that's full on, full off, and thus must cycle on and off over and over again.


How should I fit cementboard underlayment around a supply pipe collar?

You have several acceptable options:

Remove the collar and rely on mortar to retain the pipe.
Remove the collar and apply silicone to the hole to retain the pipe.
Chisel out a space in the subfloor for the collar and lower it so that it's flush.
Cut your cementboard around it and mortar over it (or just tile over the void).


200 amp panel box with some circuits not working

Wow! You got some mobile home with a 200 amp service.
The code says:

II. Mobile and Manufactured Homes
550.10 Power Supply.
(A) Feeder. The power supply to the mobile home shall be a feeder assembly consisting of not more than one listed 50-ampere mobile home power-supply cord or a permanently installed feeder.

Maybe you have a modular home?
I agree with BMitch though sounds like you lost a leg on the utility feed. You should call your utility. Might be a tree limb took out one wire of your service.


Your worst case scenario on the SERVICE is the 2 x 7-1/2HP 230V single phase motors on one bin while being unloaded, with the 10HP on the other one running the blower. 7-1/2HP 230V single phase motors are 40A each, the 10HP is 50A. You have 130A of load here. You cannot run that on a 100A service, continuous or not. So the wire size is moot.

But IF you get your service upgraded to let's say, 200A when you get the 2nd bin installed next year, then ASSuming you have a separate run from the service panel to each bin, the max worst case load would be 80A on each run, conductors must be 125%, so you size for 100A. You would need #3 Copper cable (if you can even find it), or #1 Aluminum, before de-rating for voltage drop (which I'm not going to do for you) so I would go one size larger.

If you try to do one cable run out to the first bin, then sub-feed off to the 2nd one later, you will need 2/0 (Cu or Al because of a sizing anomaly), 3/0 if there is voltage drop at that distance. That will be a LOT more difficult to run, I'd do it with separate smaller runs.


Looks like they got loose. If the connection is loose it will arc and create a lot of heat if something that draws a lot of current is plugged in.

It also looks like they got wet. There is rust and the copper wire has a patina. That would not help. If the outlets are below a water source that leaked, that could have contributed. Or maybe someone sprayed water into the outlets.

I guess they're making receptacles even more crappy these days, I'm used to brass screws which would never rust (and are more electrically conductive than mild steel). The old bakelite (thermoset) plastic receptacles also would not melt.

Incidentally, this is why connections are made in a fire-resistant box. There are also initiatives to incorporate mandatory arc detection into fuse panels. The arcing has a characteristic signature that can be used to shut down the circuit. Arcing still (rarely, fortunately) causes house fires, but it was worse when they were installing aluminum wire.


Is there a visible way to turn off this Wedgewood pilot light?

No, there is no valve visible here. On this particular model, after further searching, the valve for the broiler pilot turned out to be where the pilot gas line exits the gas distribution manifold, which is under the cooktop, by the broiler control dial. It looks like a a flathead screw. If you're going to then use it by lighting with a match/striker/lighter, then obviously only do this with a broiler or something else that is simple on-off, not something like an oven that has a thermostat.


What amperage fuse for Trane XL-80 gas furnace?

The switch is based on the load, but since the furnace is a dedicated circuit what size breaker is the unit on? I would guess a 15 amp but I haven't seen a gas furnace with anything larger than a 20 amp the switch must have a labeled on /off position but other than that a standard switch is fine.


How do I level my plaster walls and to what level?

It would be a good idea to install a tile backer board over the plaster. Over time, plaster dries out and becomes unstable. This could eventually cause your tiles to loosen or to pop off.

I would also recommend putting a thin layer of thinset mortar on the backside of the backer board. This will help attach it to the wall and the mortar will fill in any inconsistencies in the surface of the wall. Once the backer board is installed, you will have a great surface to attach your tile to. The screws in the backer board will also firmly attach it to the structure of your house, and it should basically last forever.


Can a damaged dishwasher heating element break something else?

Over the years I have bought brand new heating elements for dishwashers, stoves and water heaters that were no good. Remove the new element and check it for continuity. If you aren't familiar with this type of test, here is a Dishwasher Element Continuity Video. I would also check the resistance of the element. Turn your multi-meter dial to the ohms position. You should get a reading somewhere between 10-30.

The bad element could have caused an overload in the Electronic Control Board. This is the "brain" of the appliance. Remove the inside door cover to expose the wiring and make sure all of the wires are tight and not burnt. Smell the control board and see if you detect any type of electrical burn.


Is it safe to use Biflex TC for termite control in my house?

Some searching shows that the active ingredient is called bifenthrin.  It has been banned for use as a pesticide in the EU.

Some more links that you may find helpful:

US National Pesticide Information Center: http://npic.orst.edu/factsheets/biftech.pdf
EU European Food Safety Authority:  http://www.efsa.europa.eu/en/efsajournal/doc/186r.pdf

They have a lot of information, so they should help you decide whether or not it's right for you and your family.


Black and decker drill won’t stop spinning

My old B&d drill had a small knob on the front of the trigger. When it as screwed in (turned clockwise) it would pull the trigger in. If yours has this function try rotating the knob counter clockwise. As other have stated it is possible that debris is in the switch. Try to manually pull the switch out and see if it stopped spinning.


If the roof sheathing was replaced the spacing of the roof sheathing is most likely the issue.

You can check this by going into your attic and checking that there is spacing between the roof sheathing boards (likely OSB plywood)  board to board typically 1/16 , 1/8 to 3/16 of an inch spacing which allows for expansion, this distance varies depending on direction [top-bottom Long side to long side , width side to Width side].  The board might have an installation instruction stamped on it - that would give you proper spacing for those boards. If the board was installed with those instructions on the attic side of the board you will be able to see the directions for spacing of those specific boards from inside your attic  (if all are buckling or only a few - check the ones that are buckling and the ones closest to them).

After verifying the information above - contact another roofer mention your info and get a quote for a repair and his written explanation of what caused it.

After you have the quote; write the original roofer requesting he repair the roof as it was not installed properly (be cordial and let them know another roofer has looked at the issue as well) allow him time to respond 2 weeks is more than enough time.

During this time you can also get a free consultation from an attorney take your info with you, then if your roofer does not respond let the attorney deal with it so you can have another roofer fix it.

Of course sometimes all the original roofer needs is a letter from an attorney on the attorneys letterhead.


The type of carpet can affect the height of the baseboards.
I usually set the gap at 3/8” this is normally sufficient but some really thick carpets need a full 1/2”.
When I say thick I am talking like heavy weave like Berber where the backing is heavy and the weave is thicker than 3/8 but most carpets will fit fine with 3/8”.


Are 15A receptacles safe on 20A circuits?

That is fine. If there was only a single receptacle then it would have to match the 20A circuit. With a duplex, 15A is fine on 20A circuit. It matches your usage perfectly as each receptacle will use less than 15a and together more than 15 but less than 20.


Like someone said on the comments, sometimes a house is wired so that there are two lines going to a fan/ceiling enclosure: one for controlling the fan, and the other for controlling the fan's light (tho some fans' wiring don't allow for this type of setup). So one switch could be just going to a ceiling enclosure (where there might be just a light) and it's not connected to anything.

Edit: just saw your comment that's unlikely for a fan. Another possibility it's that it controls one of the power outlets.. you could test this by plugging a small light/hairdryer/w.e. and switch the light to see if it turns on/off the appliance you connected.


The pen looking tester should light up on the smaller hole (if the ground is down it will be on the right, the outlet tester won’t work if the hot is open someplace).
The pen is called a non contact tester (it sometimes gives false positives).
What I usually find is the circuit was overloaded or heavily loaded and a back-stab connection failed (as in, 90% chance that's it), after that, it could be that a wire nut is loose, a broken wire, or a bad wire in the panel.
I start by working my way back to the breaker panel, identifying all the dead receptacles. If I find one that seems to be on that circuit that is working, I turn off the breaker; if it turns off you will be close.
A failure in a daisy chain is always at the last working or first non-working device. Remember that a receptacle could be on the other side of the wall, yet on the same circuit.
Identify the last working receptacle or switch, pull that out, and look for a loose wire or burned insulation as a bad connection may damage the insulation or burn the wire off on either the hot or the neutral. If you don’t see anything, put the last working one back in and turn the breaker back on. If everything starts working and back stabs were used, the failure will happen again; use the screw terminals or replace the receptacle.
If it is still dead, turn the breaker off and check the first non working receptacle as it will be in one of these 2 places +98% of the time. Broken wires from nails are rare but possible or a loose pigtail in those locations can also happen, but bad backstabs are so common that you will find this advice hundreds of times on this site.


Installing GFCI outlets in multiwire branch circuit

This type of shared-neutral wiring is called a Multi-wire Branch Circuit, or MWBC.

All these issues are entirely mooted in your case, since you will not be able to use the LOAD terminals at all.  There's simply no way to do it.  You only have two receptacle sites per MWBC.  The whole point of an MWBC is to make good use of both hot legs.   Well, you need two GFCI+receptacle devices to do that.  And that fills both sites.   So the issue of extending off the LOAD terminals of one of the GFCI+receptacles will never come up.

A GFCI that doesn't use its LOAD terminals can't have a shared neutral problem.

Scenario 1:

As you propose, in box 1 of each circuit, connect the GFCI+Receptacle device to the LINE terminals only.  Connect black and neutral, and cap red.    In box 2, cap the black and comnect red and neutral to the LINE terminals.  And you are done.  There is no use for the LOAD terminals, leave the tape on them.

Before, the 8 sockets went to circuits as follows: 1.2------1.2------3.4------3.4

Now, the 8 sockets go to circuits as follows: 1:1------2:2-------3:3------4:4

Keep that in mind when plugging in heavy draw appliances.  I.e, it's no longer "pick one socket, 1 on top 1 on bottom", now it's "1 appliance per GFCI". If you liked the other way, see Scenario 2.

Now, if you need AFCI protection, you need the newer cAFCI breakers designed to work in MWBCs, that do not need the circuit's neutral wire landed on the breaker.  (the AFCI may have its own neutral pigtail, this is only to power itself.) These are all 1-pole breakers, so you will need a listed handle-tie to tie them together so they are shut off together for maintenance.  This will resemble a 2-pole breaker.

Scenario 2

This depends on not needing AFCI.

In this case, you leave the wiring exactly as you found it. You will then replace those 2-pole or handle-tied breakers with 2-pole GFCI breakers. In this you land all 3 wires (2 hots+neutral) on the GFCI breaker. You cannot handle-tie two singles because of the shared neutral.

If you can find a 2-pole cAFCI+GFCI+breaker device, you can use that.  I haven't been able to find one.

As far as the answers you're not understanding, Tester101‘s postings are sublime, among the finest on the forum. There's a lot of technical data there, and the volume of material makes it confusing when these concepts are new.  I see no conflict nor contradiction in what he wrote.

About neutral sharing, he means in the context of MWBC and protecting downline loads using the LOAD terminals.  You cannot.  The one neutral can't be both the Load side of the black subcircuit and the line side of the red subcircuit. Thus, GFCI receptacles on MWBCs cannot protect downline loads, their LOAD terminals are useless.


How do steel and enforced concrete posts compare?

I thought that there is also a safety angle here. Steel pipes tend to bend and fall over if hit by cars etc, therefore have a better impact for the ones that hit it. Concrete on the other hand does not tend to bend and therefore will cause a lot more damage to those that run into it. Of course this may have nothing to do with what you are seeing.

Here in the UK they are also rolling out collapsible frames that are used for large road signs as well so that if cars hit them they only cause minor damage to the vehicle as they bend and collapse around the car.

edit: The frames are known as Lattix. Lattix Website
      The safety aspects are demonstrated here. Lattix Safety


some baseboard heaters not working while others are in same zone

It sounds like the second floor system is split (one zone, but not a single loop of pipe) so that water is circulating in half (or three-quarters), and not in the other half (or quarter).

You either need to look harder (pull the covers off if you have typical fin-tube baseboard) for bleeder valves you are not finding, or cut the system open and add some. You have classic symptoms of air in the system, and there should be bleeders at the high points of the system, since you really can't get all the air out by bleeding down in the basement. If you have any bleeders on the working sections, certainly give them a try to see if there's any trapped air there, even though they are working.

The small-percentages possibility other than that is that the system has actually frozen on that side. Air-lock is far more likely.


AAV’s are legal in my location but they cannot be used inside walls. I usually put one in the sink cabinet as high up as I can get it that works fof the sink shower quite well and ok for the toilet.


That's very common.  Dimming LEDs is a rather complicated business, due to the need to interoperate with old style dimmers.

Older dimmers were designed to be retrofit into old-style "switch loops" where there is not a neutral.  The dimmer itself needs a small amount of energy to power itself.  The way that happened was by "leaking" a tiny amount of power through the circuit, which worked just fine with old style incandescent bulbs. But this sometimes confuses the electronic power supplies found in LEDs.

Quality problems with LEDs occur in three areas:
-  Electronic power supply (driver) operating life, particularly, capacitors
-  subtle and complex functions like dimming
-  physical build quality (the plastics falling apart or breaking)

eBay products generally fell off the back of a truck in Shenzhen, China, are unvetted for quality, and the manufacturer saved about 25 cents a unit making them as cheap as possible.  On 4 million units that's a million bucks.  Because of the capacitor issue, you can expect disturbingly short service life from these LEDs.  When that happens, don't blame all LEDs generally, blame that brand.  Quality ones will last 10-30 years.  I like General Electric, Philips or Ikea.  I avoid Lights of America, Feit Electric, Utilitech, or any big-box store house brand.


Weird wiring configuration, neutral is live

If you have two switches and only 3 wires feeding them then here is what they most likely did.

When creating a switch leg for lighting or other loads using non-metallic cable, the National Electrical Code requires that the white wire be connected to the hot feed to the switch and re-identified some other color (except gray). Usually it is re-identified with tape as a black wire because that is what electricians carry with them.

In your situation, the white wire would then be the hot feed to the pair of switches. After the switches, the black would go to one load while the red goes to another. If this is for a ceiling fan then the black would feed the fan and the red to the lights or vice versa.

This means there is NO neutral present at this switch location regardless that the wire there is white. Someone just never re-identified the white wire as is required by the Code.

To use a smart switch at this location you will need a smart switch(es) that does not need a neutral wire. It would use the ground wire to stay active while it waits for motion or a wifi signal. Apparently, the smart switch that you have needs a neutral since it has a white wire. Look for switches marked "NO neutral needed".

Good luck and stay safe!


14/2 wire 2 way switch adding 14/3 wire to make it a 3 way

On the 14/3 cable, tape the white wire with black electrical tape on both ends. This is always-hot.

Tape the other two wires with yellow tape on both ends. These are travelers.

The reason to mark with tape is a) with white it's the law; and b) with yellow, it turns a typically very confusing 3-way box into easy mode. 3-ways are notorious for having no color codes at all, and your next 3-way might have white/red travelers.

In the existing switch box, there should be two wires on the switch.  Whichever one is always-hot is attached to the black-taped white wire from the new /3.

Next, in each box, the 2 yellow-taped wires are put on the 2 brass (yellow-ish)  screws on the 3-way switch.

In each box, there should be 1 wire left.  That goes on the black screw of the 3-way.


Wow you need more help than we can provide IMO.
First you need your well log to see what the wells should be capable of.
With the lift you have I have normally had much larger pumps but your well log should show what the flow rate is after 3 hours of draw down and
what the water level is at static.
Then you may need a cycle timer to work in series with your pressure switch and the big pump.
With it pumping “dry” for long periods with that lift it will wear the pump heads out.  Cycling will allow the well to recover cool things and cycle and draw down again. you may find that is much more efficient.
How old is the deep pump? Consider it may be worn out. 400’ lift followed by several hundred more ? The pumping chart I looked at topped out at 500’
I did set up a deep well with a large tank at the well head then another pump in that tank to another all interlocked so no tanks over flowed, this allowed the use of much smaller pumps and provided improved performance.
If your 1-1/2 hp is pumping it will be drawing up to 10 amps all the time at a 3/4 gpm flow if you could let the pump rest for 30 minutes then pump for 10 you can see your flow rate should increase for those 10 minutes up to 6 gpm at the pump I looked at and your energy usage will be cut drastically.
10 amps x 240 volts = 2400w  that’s 2.4 kWh every hour x 24 hours per day 57kwh per day , x 30 or 1700 kWh per month rounded down what do you pay for power? Even 10 cents is 170$ per month just for that 1 pump so a cycle timer could pay off in a week or 2.


How can I restore the shine to a quartz countertop?

Do not use sealer on engineered stone, it has to be mechanically re-polished if it's lost its luster due to abrasion. If you're lucky it's just dirty.

Of course, you cannot apply a sealer to Silestone quartz countertops, so it's just a matter of cleaning it. –countertopspecialty.com

Do not use oil-based soaps for this. Dulling of the shine occurs because of residue left behind on the countertop. Oil-based soaps are often used on porous surfaces because they are designed to soak in, not to be completely removed. Standard dish soap is best. [...]
To remove cooking film from the quartz, spray the space with window cleaner. [...]
Avoid Using More Polish. Quartz countertops are polished within the manufacturing company, using a sealing surface polish. Further polish added to the top will only create excess buildup which will further the dull look.
–How to Polish a Quartz Countertop to Make it Shine, doityourself.com


How can I support a room expansion that will extend above a garage slab?

A diagram with dimensions would help.  But supporting the floor is the easy part - basically, you'll need to build a cripple wall, framed with 2x4 lumber, to support a rim joist that you'll hang your floor joists from.  Set the cripple wall on a pressure treated plate lagged to the floor with concrete anchors.  Floor joists will be sized with a span table  Note that your garage floor should be sloped from back to front - you'll have to accommodate that in your framing to end up with a level floor.

You'll also have to determine if the wall at the back of the garage that you're intending to remove is load bearing or not.  If so, that will be alot more work involving a licensed engineer, to figure out how to do that correctly.  You'll also have to figure out how to support the new floor at that side, so you'll need to understand the framing & foundation of that wall.

Not sure where you're located, but most US building codes have specific rules about the walls between a garage and living space.  Things like type & thickness of drywall, fire rated doors, sealed penetrations etc.  You'd do well to check the codes for your community before you go to far.


If it's only that one sink it very likely is caused by corrosion or blockage between the shutoff and the faucet. The hot water side is especially susceptible to scale buildup. There are a few basic things to check:

First make sure the hot shutoff valve is fully on.
If the shutoff is old it could have scale buildup in the shutoff valve. Turning it on and off a few times will sometimes free it up.

If the hot is a separate faucet:

Remove the aerator from the faucet. Clean the screen of any debris.
Turn off the hot shutoff valve and remove the hot water cartridge and check it for scale buildup.

If there is still a flow issue I would replace the shutoff valve and/or  the hot water cartridge starting with whichever one looks most suspect. This should solve your problem.

Edit
Another possible cause, but less likely, is galvanic corrosion which happens when two different metals are connected such as galvanized pipe coming out of the wall connecting to copper. This requires a special type of connection (dielectric union) to prevent corrosion.


Magic 8-Ball
Harper calls these "magic 8-balls". If you don't really understand them, they are about as useful as a Magic 8-ball.
The original versions of these (and still available) have 3 lights connected across hot-neutral, hot-ground, neutral-ground. The newer testers - like yours - use a microprocessor and some fancy circuitry to simulate the 3 lights and provide additional information.
Wrong circuit!
While this particular device (and many others) can handle a wide range of voltage & frequency (just like a laptop power supply or many other things), it does require a particular combination of wires to work as designed:

Hot - called "Live" on this device, also called "Line"
Neutral
Ground

One key thing to remember is that the electrons moving around (usual metaphor for electricity, though the physicists argue about the details) do not "know" what is supposed to be Hot, Neutral or Ground. They just "go where they can, the fastest/easiest way that they can get there". That is why problems with "lost leg", "lost neutral", "ground fault", etc. can be so dangerous. But it is also why a tester like this is extremely limited in what it can tell you. It can sort of say something is "reversed", but only if everything else is normal.
You connected, TWO HOT WIRES and no neutral. So things won't work right, as you found out the hard way. Among other things, Neutral to Ground is 0V on a Hot/Neutral/Ground cable but you replaced Neutral with another Hot wire, so Hot -> "Neutral" is 240V instead of 120V (that's OK on this particular device) but "Neutral" -> Ground is 120V instead of 0V, which is not OK - and turns on an extra light.
How the lights are SUPPOSED to work

Light 1: Hot -> Neutral. Normally ON. Off if Hot or Neutral is open (because the light can't get power from an open circuit) or if Hot and Ground are reversed (because Ground and Neutral are normally bonded so no power flows between them)

Light 2: Hot -> Ground. Normally ON. Off if Hot or Ground is open (no power in an open circuit) or if Hot and Neutral are reversed (because then this is Ground and Neutral).

Light 3: Neutral -> Ground. Normally OFF. On if Hot and Ground are reversed (because then this is Neutral & Hot) or if Hot and Neutral are reversed (because then this is Hot & Ground).

So each particular light tells you about voltage between two wires. But it doesn't really tell you what is going on. The combination of all 3 lights gives a good indication of what is likely to be going on.
The Problems
There are a lot of possible problems. Let's start with one that is clearly a problem on this device: All lights on == Live/Ground Reverse, Missing Ground
Guess what? There is NO SUCH THING!
My trusty Klein RT105 doesn't have "all lights on" on the label? Why? It does not exist in any normal circuit - and if it exists, the magic 8-ball has no idea what it means!
It can't really mean Live/Ground Reverse AND Missing Ground - if the Ground is missing, it is not "reverse"! They really should not have put that label on there - better to just leave it as "all lights on should never happen, so we'll just pretend it can't happen - and except for someone trying to put in a 2nd hot instead of neutral, it doesn't happen.
All it really means is "enough voltage on all 3 pathways to turn on the lights". In your case, that is:

Light 1 - Hot 1 -> Hot 2 = 240V
Light 2 - Hot 1 -> Ground = 120V
Light 3 - Hot 2 -> Ground = 120V

There are additional possible problems, such as blinking or dim lights, which could mean all kinds of possible problems with your circuits.
The end result is that:

These devices are primarily useful on the circuits they are designed to test - Hot/Neutral/Ground.
If the display is anything other than "Correct", the lights are a suggestion but not a guarantee of what is/isn't correct in your circuit.

I mainly use these as a double-check. If everything seems OK and the tester shows the correct lights, I'm good to go. If something already seems "wrong", this kind of tester doesn't tell you much of anything. And if I am going to a new (to me) receptacle to check things out, then the tester gives me a very good first indication of correct/incorrect - but if it says incorrect then it is time to open things up and check everything methodically until I figure out the problem.


Can an outlet for a dishwasher be located below the floor?

You are correct, the issue here is the cord and plug for the dishwasher running through the floor.

  400.8 Uses Not Permitted. Unless specifically permitted
  in 400.7, flexible cords and cables shall not be used for the
  following:
  ...
  (2) Where run through holes in walls, structural ceilings,
  suspended ceilings, dropped ceilings, or floors

Running the cord inside the cabinetry does not break this rule.

Contrary to other answers, in my opinion, the cord and plug connection for the dishwasher is perfectly fine and makes it easy to disconnect power.


Here are a few things worth trying:

I reckon a hot wash would give you a few hours of respite from the smell, and nothing you've tried cleaning it with would do much against congealed grease. A dishwasher cleaning product or even just a full dose of detergent with it empty would be better.
After this, try to figure out where the smell comes from first, to narrow down the problem.
Damage to the drain hose or sump can cause a (slow) leak, and that can smell. In our case a mouse that the cat brought in chewed through the drain hose, and the first clue we had was the smell because the volume of water each time was too small to get right out. Replacing the drain hose is a bit tedious but not expensive or hard. Any leaking water could end up inside the unit so check there as well.
If there's an open pipe above a trap you may need to clean the trap (caustic soda, though the dishwasher cleaner might take care of this). If the trap is full of grease it can cause the outlet pipe to overflow.


I have rarely found a faucet I can not repair. Yours needs a new valve stem packing no problem even if you cannot get the handle off.
Move the nut as far as you can to the handle.
I use expanded goretex rope for valve stem packing, some has graphite and is easy to install. 1/2 a dozen wraps of this will solve most valve stem leaks. I replace the washer when I do this screw the valve back on then tighten the jamb nut, if it still leaks you can loosen the jamb nut and put more wraps of packing, in a pinch I haven used the Teflon tape quite a few more wraps are needed but it will seal. Tighten the jamb nut and turn the water on again. I have repaired valves that were over 100 years old doing this 5 minute repair procedure.


Sprinkler valve not turning on by automatic timer

You have done good testing. Almost certainly the electric solenoid at the valve is defective, with a small chance the wire has a short.
Many designs of them can be replaced (leaving the rest of the valve in place).


Won't work.

From the 3-core cable, and from the fact that all wires of each cable go to 1 switch, it's perfectly clear that this is a 2-way (USA: 3-way) switch.

And further, it is the switch on a "spur" line.

In this location, those three wires will be 2 travelers and a switched-hot.  None of the wires are hot or neutral.  So it is not possible to add a smart-switch here,  except by greatly reconfiguring the entire circuit.

However, it may be practical to fit a smart-switch at the other 2-way location, depending on which wires are there.    If it, too, is a spur, then smart switches will require a dramatic reconfiguring of the whole circuit, and to help you there, you'll need to supply a lot more information about what is going on inside the other switch box and at the lamp.


What wire size for 100 Amp sub panel 100ft in length form 200 Amp main panel?

Alright here we go. A circuit size is defined by the overcurrent protection not the of the equipment attached to it. For example your question. Are you planning to protect the circuit with a 100A breaker? If the answer is yes then you need to run at least #3 Copper or a #1 Aluminum conductors. If you install a 70A breaker then you can reduce your conductors to #4 cu or #3 al. Of course none of this takes voltage drop into consideration.

Voltage drop is calculated using your power demand or all of the electrical equipment, lights, devices, and appliances you are planning to use at one time. If you don't have that information then would it be safe to assume that you are using the 80% rule on your feeder size? Meaning you are only going to load your circuit to 80% under normal circumstances. If the answer is no I want to use the full 100A then you feeder would have to be raised 2 sizes to make up for the voltage drop to a #1 cu or 1/0 al. If the answer is yes then you will be able to stay at the original size. The main reason for you to consider this is the cost of material. Conductors a few size larger can become rather expensive. Which is why I mentioned a 70A feeder which would also reduce your cost. I would suggest you take a good look on how much power you are going to use and think about what size feeder you are going to need.

As far as whether you can reduce a neutral once again we have no knowledge as to what type of equipment you are using. If all of the load is 120V then no. If there are some 240V loads then yes but we have to know how much will be permanent.

Your grounding conductor must be run also and it is sized to the breaker also. A 100A breaker would require a #8 cu or a #6 al. If you are calculating full load then the grounding conductor must take voltage drop into account and rise a full two sizes more just like the current carrying conductors or a #4 cu or #2 al.

So once again take some time and think about what you need. I hope this helps or at least sheds some light on what you are trying to do. Good luck.


What can I do about toilet water disappearing?

I share Paulster2's concern that your plumbing isn't properly vented, or there's a blockage in the vent. You can try to snake the vent from the roof or running a garden hose down it to clear it out.

Signs of insufficient venting include drains that start slow and then gurgle after at the end, toilets that bubble, especially on lower levels, and traps that get sucked dry, especially on the upper levels.


Bathroom bulb only giving off weak light

Fluoresent ballasts do go bad. If it is a very old fixture it may have a starter:a starter is usually a small tubular module with 2 pins on 1 end - a twist, usually CCW, and it will come out. Starters used to be very common; if you find one it is probably bad. If no starter, the ballast has failed (not uncommon).

Changing a ballast is a simple procedure: turn the power off, open the fixture and record the part number on the existing ballast. Find one online or locally. Usually there is a line diagram of the connections. If you get a different brand, you may need up to 6 wire nuts: again with the power off, cut the black and white at the ballast and connect to the new ballast. Next is the lamp connections - many mfr's use the same color-coded wiring. If the wires on the old ballast match the new one, finish cutting the old ballast out and wire nut the wires together. If the colors are different, compare the line drawings on the 2 ballasts and transfer to the new ballast using the diagram on the old ballast. This is what electricians do.

I have changed thousands of ballasts over the years and I still need to look at the instructions. Ballasts are a DIY item in my professional opinion.


What material should be used behind a sink and range in the kitchen?

Hardibacker makes a board that can be used instead of drywall (its the same thickness). tiles can be put right onto it. Thats in the US anyway.


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

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

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

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

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

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


What tool can I use to cut this heavy wire?

A bolt cutter or hack saw will make quick work of it, as would an abrasive blade in a circular saw or angle grinder. It appears to be soft iron judging by the rust.


hydronic floor heating system efficiency - using concrete as thermal energy store or not?

A very important factor in deciding to use a thermal mass to store energy is the energy source. Solar energy is the classic example. The energy is free and the supply is periodic and unpredictable. Energy storage is a must.

You mentioned a boiler, so you likely are burning fuel, directly or indirectly, or at least paying for the supply. In this case, energy being of significant cost and in virtually ready supply, energy storage is not warranted. The inherent losses in the store/release cycle make it of little benefit. Especially with only 2.5cm of insulation.


How to seal where the wall meets the floor?

There are several ways the air can reach the gap between the floor and wall.  Your best solution would be to find the entry point and seal it there.  Unfortunately, that's almost impossible so your next best answer is to seal the gap between the wall and floor.

Your first answer, caulking above & below the baseboard, is the least obtrusive but would be the least permanent.  As the wall and floor flex with changes in temperature, humidity, and load, the 2 seals could break loose.  The seal against the floor is also likely to be knocked loose with regular sweeping and foot traffic.  Although better than no seal, it's not my preferred approach.

I did similar to your second answer in the laundry room of my own 1929 home.  I removed the baseboard & trim, stuffed any gaps over 1/8" (2-3mm) with foam, then caulked over the foam and reinstalled the trim & baseboard.  It's amazing how much air leaks through such a small gap!  The water lines to my washer froze several times before I sealed the gap; the space hasn't dropped below 50F since I sealed it.

If you remove the hardwood to replace it, remove the trim as well and use the opportunity to seal any gaps where the wall meets the floor.  Walk around the floor inch by inch and screw down (not nail!) anyplace that moves or squeaks.  A simple web search will find more about eliminating floor squeaks.  Also look into a roll underlayment to go between the subfloor and new, floating, laminate.  This would isolate the laminate from the subfloor to eliminate another source of squeaks and cover gaps in the subfloor, reducing drafts from below.


How do I install a butcher block breakfast bar on a half wall?

I have a similar bar/half wall situation, but with a granite top instead of butcher block. In my case, I screwed a piece of MDF to the top of the half wall, and the countertop installers then glued the granite to that with a strong adhesive. This works because the granite is doubled at the edges, so the MDF is mostly hidden. If it would be feasible for you to rout the bottom of the butcher block 1/2" deep everywhere except the edges (I'd suggest leaving an inch around the edges full thickness), then you could do pretty much the same thing as me, with a layer of MDF screwed to the wall to provide support for the butcher block.

Make sure that the MDF is installed level - otherwise, when you level the butcher block, you'll have MDF peeking out from under it at one end. Don't ask me how I know...


Can I insulate PEX pipe in a crawlspace with fiberglass insulation?

Should work fine-ish. Use more UN-Faced insulation to avoid moisture problems.

It's only fine-ish (rather than fine) because the pipe is more than halfway through the total insulation, leaving it somewhat subject to freezing if it gets cold in the crawlspace.


Why is it said that a typical 120V household circuit "reverses" polarity?

My previous answer was a bit unclear, and a bit misleading. So I'm going to take another stab at it.

As before, we'll start by looking at the secondary side of a single split-phase transformer. And again, the loads are represented by purple rectangles.

Then we'll spit the circuit up into individual circuits, so we can take a closer look at each circuit.

If we visualize the current flowing through the circuits in the first 60th of a second, the current will flow like this.

During the next 60th of a second, the current will flow the opposite way.

The interesting thing about this, however, is if you look at the current flow on the neutral.  When you overlay the images, you'll see that the current flows both ways simultaneously on the neutral.

Because of science, the opposing forces cancel each other out. However, if one force is larger than the other, the current will not be completely cancelled out. So the "unbalanced" current will flow on the neutral, in whichever direction it's flowing during that cycle.

So technically, you could say the current is flowing both ways, and neither way (if they completely balance) at the same time.

Extra Credit

Facts

Neutral is always "0" volts.
L1 and L2 cycle from positive volts, to negative volts (alternately).
Energy always flows from points of higher potential, to points of lower potential.

Therefore...

When L1 is greater than "0" volts, current flows from L1 to N.  When L1 is less than "0" volts, current flows from N to L1.

When L2 is greater than "0" volts, current flows from L2 to N.  When L2 is less than "0" volts, current flows from N to L2.

When L1 is at a higher potential than L2, current flows from L1 to L2.  When L1 is at a lower potential than L2, current flows from L2 to L1.


Is it a good idea to paint during Winter?

Absolutely not accurate!!!!!!   There is no reason not to paint inside as long as temps are above 60F. Today's latex acrylic paints dry fast, adhere well, and apply well in moderate temps.( we always use some flowtrol to make it work longer and spread smoother) Actually, in winter the relative humidity is usually lower, so paint dries faster than in the heat and humidity of summer. Longer dry times lets more dust adhere.   Go for it during the winter, then you will have more time to enjoy the out of doors come summer time!!!!


Can I replace a 30A breaker with a 40A breaker for a new water heater?

Your current 30A water heater circuit was probably wired with #10 solid copper. You can confirm this by inspecting the stamp or printing on the cable jacket, or by using a gauge measuring tool (with the power safely disconnected).

A 40A circuit typically calls for #8 copper wire, which is usually stranded. It's a markedly larger cable bundle. If you don't have that, DO NOT increase the breaker size. A circuit breaker's primary function is to protect wiring from overload, and a 40A breaker does not adequately protect #10 wire.

This is standard advice and doesn't apply to inordinately long runs or other nonstandard scenarios which may call for even larger wire.


How to fix leak coming from pressure gauge on water tank?

What you pointed at is the pressure relief valve. Seeing that the pressure is fairly low, it  could either need adjustment or be failing.

The pressure relief valve is basically there to release very high pressure before a pipe/filter/faucet relieves it (eg: blows up).  It's basically just a spring pushing against a piston.

You can try adjusting it first by turning the end clockwise just until the flow stops. Best to do this at the pump cut-off pressure (which is the highest pressure you'd normally see) -- basically open a tap until the pump runs, wait for the pump to shut off, and then adjust the relief valve.  A lot of the valves actually have a ridged edge you can turn, though yours looks like it probably requires a nut/screw driver or pliers.

If that doesn't work, it is probably just that the valve is failing. Could be a cheap valve or have a manufacturing defect, or could be corrosion. Replacements cost a few dollars at any home improvement or plumbing store and are very easy to install (use teflon tape on the threads).


Loud noise from outdoor unit several seconds after AC turns off

If there is a bad spring in the compressor , the compressor can be replaced, you do not have to replace everything.
  In cooling mode the outside unit should never need a defrost the condensing coils are actually hot, if there is any ice it would normally be on the suction line and is normally caused from a low charge but an over charge can also cause icing.
As far as the torpedo noise I am not sure what you are describing but if non compressibles (air) has gotten into the system it can sound louder as the high side pressure drops once the compressor stops. With the noise and possible icing it is time to call a tech and make sure your unit has a proper Freon or refrigerant charge. As far as a home warranty if it is covered you should use it but at this point a service call is needed to identify what the problem is. You should get a recording of the noise so the tech can hear it it could be something like the reversing valve opening since you mentioned the temp set back but that is a guess, as It is really the only thing I can think of that would really dump the pressure and make a noise intermittently.