AFCI breakers/protection and refrigerators - a bad idea? The 2014 NEC requires AFCI protection for refrigerators. I've read that one shouldn't use GFCI protection for a refrigerator, but I know that AFCI breakers do include ground-fault protection (at a 30mA threshold, as opposed the 6mA threshold for GFCI breakers or AFCI/GFCI dual breakers).

Are nuisance trips a problem when using an AFCI breaker on an individual branch circuit for a refrigerator?

And if so, I'd be curious - are the nuisance trips typically due to false-positive ground faults (difference between line and neutral current - as a GFCI breaker would detect), or false-positive arc faults (series arcing or line-to-neutral arcing)? I believe most of the AFCI circuit breakers on the market will distinguish between those two, in order to help diagnose the wiring problem.

Some good info about GFCI and refrigerators here: Why is GFCI tripping on refrigerator circuit?

The question presumes something I do not believe.

I don't believe all AFCIs also do GFCI at 30ma level.

This answer here is a very well-informed and interesting exposition on how many AFCIs were given a "weak" GFCI function to detect arc faults to ground.  But this was less than ideal - not least it requires you make a whole line of 2-pole AFCIs; in most of those applications, handle-tying two 1-pole AFCI would suffice if the AFCI didn't need to do that GFCI-ish thing.

This lesser protection was typically 30ma.   Remember, 30ma protection is inadequate for kitchens, garages, basements or anywhere else NEC requires GFCIs.

Some people believe AFCIs are required everywhere GFCIs are not.  The NEC does not say that.  If your local inspector says so, you need to have the discussion with them.  You can fight city hall, but it's cheaper to just replace that problematic fridge.

Refrigerators are not the use-case for AFCI or GFCI

GFCI is to protect people from shocks, typically from lightly insulated plastic gadgets getting broken or wet, or the user having contact with an energized part of a 2-prong tool.  This is absolutely irrelevant to an immovable box with a steel chassis, all the 120VAC gear inaccessible at the bottom rear, and a fully plastic inner lining.  It would be nigh impossible for a consumer to contact anything 120V if they were trying.

AFCI is to prevent fires from wiring faults either in house wiring or in plastic, flammable devices.  Being entirely contained inside an all-steel box, it's nigh impossible for a wiring fault inside the fridge to start a fire without also pulling enough current to trip the breaker.  Yes, the cord, receptacle or in-wall wiring could have a problem; but consider the same logic that is applied to the NEMA 10 receptacle: this is fixed equipment with a typically inaccessible receptacle, which is rarely unplugged or moved.

Sometimes, a ground fault trip is a ground fault

I do see a lot of forum posts like

  My old fridge never tripped the GFCI before.  Now suddenly it's tripping the GFCI a lot.  Why do fridges need GFCI protection anyway? Can I remove the GFCI protection?"

Sometimes, a GFCI trip is exactly what it says on the tin --  "working as intended" genuine trip caused by faulty machinery.  Often cleared by a good cleaning, but sometimes, you just need a new fridge.  Insulation failure is one way machines fail.


Is it worthwhile to replace evaporator coil? My AC condenser is done for and needs to be replaced. The evaporator coil is 15 years old and still working. I could get both replaced at once, or just replace the AC condenser. Doing both will cost around $2300 more than doing just the condenser. Is it worthwhile to do both, or better to just do the condenser.
Another option might be to install a heat pump to replace both, but I'm not sure if that's how these things work. I'm a layman and don't know much about these topics.

I would replace a 15 year evap coil. Since the efficiency of the condenser/compressor has changed (more efficient), you also need to match it with the proper evap coil and metering device (TXV).


Proper way to ground a 240v metal outlet box? I am replacing the circuit to our stove and am doing the rough in currently. We may one day want a stove requiring more amperage than our current 40 amps and so I am replacing with 6-3 w/ground. I have the wire stripped back and pulled into the metal receptacle box and am trying to find a code compliant way to connect the bare ground from the cable to both the outlet and the metal box. I have seen and read about numerous different ways to do this but don't know what is code compliant.
I have looked into purchasing a grounding pigtail and read that any grounding wire I purchase to help connect the metal box to the wiring and outlet needs to be 10 awg as this gauge is good as a grounding wire up to 60 amps. Because the 6-3 is good for 55 amps the 10 ash as a grounding wire is what I need. If I am wrong about this please let me know.
If I can go with a pigtail then...

where do I find a 10awg pigtail? I can only seem to find 12 awg pigtails.

If i can't find a 10 awg pigtail then is green insulated thhn wire in proper gauge acceptable?

how do I connect it all? Can both the pigtail and the bare ground from the wire be placed into the receptacle and screwed down or is there a different way I need to connect them?

Thank you for your input and if I left out any needed info please let me know.
Ben

Take the #10 AWG ground from your cable and loop it to your metal box with a 10/32 grounding screw. There should be a threaded hole for this in the box.  Extend the ground outward an attach it to your outlet.


How can I wire multiple outlets controlled by a single switch? I’m trying to wire multiple outlets that are powered by a switch. I do not need to split the outlets. The power is coming to the outlets from the panel first. The switch is on the end of the run. Would prefer a diagram for the answer.
Thanks

If the switch is at the end of the run then you will need 3-conductor cable between the several outlets and between the outlets and the switch.

Pass the hot through all the outlet boxes to the switch via the black wires.
Pass the neutral through all the outlet boxes to the switch via the white wires, and also connect the neutral to the neutral side of each outlet via white pigtails.
At the switch, leave the white neutral wire capped off. This is required by code against the possible future installation of a powered switch.
Connect the black and red wires to the switch. The red becomes the switched-hot.
Pass the switched-hot back to all the outlets via the red wires. At each outlet except the one furthest from the switch, connect the hot side of the outlet to the switched-hot via a red pigtail.
Using the pigtails as illustrated will avoid the potential embarrassing situation where a connection fails at one outlet but other outlets stop working.
Also note that if in future you decide to split any of the outlets, you already have constant-hot available in every outlet box.


How do electric hot water heaters explode and what can be done to prevent that from happening? My neighbor and good friend is a union steamfitter, and general handyman. He had to replace his electric hot water heater last year and he did it himself.

My wife and I have to replace ours now, and he says its a super simple job and he has offered to help me do it. I came across this article and many others that warn that these heaters can actually explode if installed improperly, and it has us a little concerned (to say the least!).

I understand that the knee jerk, default response in these situations is: if you feel uncomfortable doing this yourself, have a professional do it. And I get that, I really do. I'm just trying to weigh all our options here.

So I ask: under what conditions can electric hot water heaters explode? It sounds like (if I'm reading these articles correctly) that they explode when both the temperature is set too high and the expansion tank is malfunctioning. So if that's the case, then my followup question might be: OK, well, how hot is "too hot" and how can I test my expansion tank to confirm its functioning properly?!

However, if there are other instances where these types of heaters can explode, I'd like to know about them, and what the diagnostic/operating procedure is to prevent those situations from happening.

At the end of the day, if I don't feel 100% confident in the process, we'll have a pro do the install. But if its as simple as checking a few things or taking care to avoid certain specific pitfalls, I'd rather save the ~$2500 and just do the install with the help of my handy friend.

Yes, that's a scary article but keep in mind that both safety devices have to fail to have the tank explode. The pressure release valve and the high limit on the thermostat both have to malfunction. Both of them to my knowledge operate at around 200 degrees F. The maximum you can set most water heaters is 150 degrees F but most recommendations are to set them at no higher than 120 degrees F. Also you should check and test the pressure release valve periodically for leaks and operation.

Replacing the water heater is a relatively easy task. Just make sure it's completely full before turning on the breaker or you could burn out the elements. Also, avoid using those corrugated pipe. Sweat copper tubing all the way. Your steamfitter friend can instruct you on this. Good luck


Plastic tailpiece on brass bathtub drain? I have a new tub that came with the drain & overflow pre-assembled, but no tailpiece. I found a plastic tailpiece for $5 and I would like to know (1) if it's OK to use on this drain and (2) how to install it correctly. (The tailpiece packaging just says "plastic"; can I assume since it's black that it's ABS?)

The drain itself looks like brass. I have access underneath the tub, so no problem there.

The tailpiece came with a nut and two washers. Is this how I should fit them together (see photo)? Should I apply putty or anything else (I think not)? I tested just the nut on the drain, and it seems like a snug fit. [EDIT: When I try to assemble everything as shown, it doesn't fit because the nut threads can't reach the threads on the drain. So basically, I have no idea how to connect this tailpiece.][EDIT #2: After watching a YouTube video "How to replace a sink tailpiece" (StackExchange won't let me link directly), I removed the extra washer that I had slid down the tailpiece. See the red X's on the photos. Now it fits. Hopefully there won't be any leaks. Comments are welcome!]

Then of course there is the P-trap. I'm just planning to slip the tailpiece into the adapter and tighten. I'll probably shorten and debur the tailpiece first, though.

Does this all look OK? Would a brass tailpiece be safer (less likely to leak)? I'd like to avoid problems as much as possible. Thanks so much for any advice!

It's probably nylon, but it's all fine. Almost every concealed drain uses plastic of one type or another these days.

Those fittings are all compression-actuated. Often the entire trap is also so it can be disassembled for cleaning when needed. Don't use caulk or putty. Tighten them about as tight as you can get them by hand (unless you're a bricklayer).


Why is my Australian light fixture wired this way? I just want to replace it with a new light fitting philips tcg701 but there's way too many wires and I don't know why it was done this way.

It's fairly standard

In your case the red/white pair is probably from the switch, red probably live and white switched live (normally in my part of the world it would have red tape on it to indicate switched live). The other two twin+earth cables are mains supply and continuation to next light fitting. Your wires were connected directly to the light fitting so there is no separate cable to the lamp.

You can confirm this with vary careful one-handed testing using a suitable Cat II rated mains voltage tester. You can get non-contact voltage testers that make this safer.

After testing and confirming above, I'd connect the new lamp to the black group (AC neutral) and the white wire (switched live)


How to prevent mosquitoes from breeding in my swamp cooler? Today I decided to clean the water-pump filter of my swamp cooler, and there were a couple of larvae swimming in the water reservoir and some mosquitoes flying over it. I am looking for a way to kill the larvae and prevent the mosquitoes from breeding here in the future.

I can't drain the coolers everyday. It is a tedious chore if done manually. And it wastes a lot of water (around 70 liters per unit). Also I suspect that some puddles will remain in the cooler even after draining.
I can't use bleach or insecticides. The water comes into direct contact with air that people will breathe. I tried bleach a couple of years ago and it gave off a horrid smell.

So what other effective steps can I take to solve this problem? Doing some online research, someone suggested that I should add dish-soap to the water. Will that even work?

BT ( bacillus thurngensis ) will kill insects . It is not a biocide so will not affect animals.It kills anything with an alkaline stomach and has no affect on anything with an acid stomach like an animal. Commonly available at garden shops.I can't imagine a problem in your system. It can be put into ponds as it does not affect fish. It can be sprayed on vegetables right up to harvest and is safe to eat. I expect you would put in the same dose as recommended for a pond of the same volume.


Thermostatic shower valve with tankless gas heaters Are there any benefits to using thermostatic shower valves when my tankless gas heathers already limits its maximum temperature at 48°C (it can only reacho more up to 65° by disabling the safety feature).

This heater modulates the flame so that the output temperature is near constant. I understand that if something sudenly draws cold water the temperature might rise, but I doubt it would me much of a concern.

Thermostatic valves are more expensive, bigger (two dials vs a single monocomand mixer) and its replacement cartdrige is much more expensive than a regular one.

Other than scald prevention, which isn't much of a concern with 48°C water, the other "features" are being able to set a maximum temperature, and attempting to maintain temperature when the pressure on one side dips.

Since you say that you set the heater near your bathing temperature, then it sounds like those other features won't do much for you since you're using almost 100% hot water rather than a mixture of hot and cold.

I don't set my water heater much higher than yours, but I still like the ability to adjust the maximum temperature in my kids bathroom.  I have it set where it doesn't even get hot enough for me to take a good shower, but its perfect for their bath and can't get hotter than they would like.


I need to remove this deadbolt but it's not coming off I'm removing an old Kwikset deadbolt circa 1995 I got the handle set part out but this deadbolt has some type of protective casing and the front is not coming off nor the back.

Here's the back side.

Looks like it is a double cylinder deadbolt (has key cylinder on both sides). Use a flathead screwdriver to remove the two black bolts.


resoldering copper waste pipe I've soldered new copper pipe but have never resoldered it.

A shiny band of silver solder remains on the end of the copper pipe after an elbow has been removed from it. Does that shiny band have to be sandpapered away, to get down to bare copper, before flux can be applied and a new elbow installed?

This is 1-1/2" copper drain pipe (DWV), if it makes any difference.

The main problem, if any, assuming the solder band is complete and without flaws or gaps is if there's too much solder on the pipe and you cannot insert it into the fitting. The pipe is "tinned" or coated with solder, and there's nothing wrong with that.

The usual approach to making sure that the coating is thin enough is to wipe it down (while the solder is molten) with a rag - easiest if done when you heat it up to take it apart, but you can heat it up again and do that if the fitting won't seat properly as it is. That should leave it thin and nearly mirror-shiny, which is what you want. Caution is needed as you are dealing with hot, molten metal.

The basic secrets of soldering are that things should be physically clean (shiny metal) chemically clean (use appropriate flux) and not overheated (too much heat burns off the flux and solder won't wet the newly-oxidized surfaces.) The silvery solder is perfectly fine shiny metal. Dull gray solder needs to be cleaned up, but there's no need to go to copper.


Flexible PVC to flexible metal conduit connector I had planned to install a new run using flexible PVC conduit, but discovered a section of metal conduit already in place within a wall I can reuse. Is there a way to directly connection PVC and metal flexible conduit without needing a junction box?
I'm not adverse to using a junction box, just thought a direct connector would save time & effort.
Thanks.
i.e. connecting these two conduits...

Yes you can convert from liquid tight to metal flex you need a end for each and a coupling to connect the two. If both are 1/2” for example a standard 1/2” conduit coupling Will allow the two to be connected without a box.


Are you supposed to leave the pigtail lead on an GCFI / AFCI breaker curled up? Here's an example of the kind of breaker I'm thinking of:

They come with the lead neatly curled up. Is this curl meant to be maintained for some reason once the breaker in installed? Or is it just a convenient way to store the wire for packaging purposes?
Assuming you don't need the curl, then I guess it would be correct (or at least, acceptable) to straighten it out and route it neatly in the panel box the same as you would any other wire?

Note - as far as this question goes, I'm not asking about the actual electrical details of where the wire gets attached, just about this curling issue.

There is no reason electrically to leave it curled up. You'll be perfectly fine straightening it out.   I'm assuming this is an add on to an existing panel.  If a new panel, I'd seriously consider a PON (plug on neutral) style panel.  This eliminates the need for the pig tail.  Last year I  wired my son's new house with a SquareD PON QO panel and loved how it turned out.   Very clean.


wire gauge for dual driven appliance (solar inverter) I've been thinking about the #8 wire between a sub-panel, on a 50 amp breaker, and a 10kw solar inverter.

Between the 50 amp breaker and inside the inverter, in the event of a fault, the wires would be driven on two sides, potentially at upwards of 90 amps continuously.  The size of the wire between the inverter and sub-panel was sized by the 50 amp breaker - #8, and is contained within PVC conduit.  Inside the inverter the wire is both #8 and ~#16.  The #16 wires goes to a WattNode power meter that consumes ~1 watt.

How is that #8 is allowed between the appliance and the breaker, and within the appliance, ~#16?

This is within the US and is for a SolarEdge 10k inveter.  Sub-panel has 100 amp bus bar, w/utility at top and solar at bottom.

The NEC has no bearing on factory wiring within listed equipment

The gauge of factory wiring in listed equipment is governed by the applicable UL standards and by the testing UL conducts in accordance to those standards (usually various temperature rise tests) as part of the listing process, not by the NEC.  This is reflected in NEC 310.1:

  310.1 Scope. This article covers general requirements for
  conductors and their type designations, insulations, markings, mechanical strengths, ampacity ratings, and uses. These
  requirements do not apply to conductors that form an integral
  part of equipment, such as motors, motor controllers, and similar equipment, or to conductors specifically provided for elsewhere in this Code.

As a result of this, we must look outside the NEC for an explanation of this.  While I have not seen explicit provisions for these sorts of potential or control taps in what I have been able to read of UL 1741, the UL 508A standard for industrial control panels contains a provision in 41.1 Exception 1 that can be used for an argument by analogy in this case:

  41.1 The conductors of a control circuit tapped off the load side of the branch circuit protective device
  shall have overcurrent protection sized in accordance with the ampacity of the control circuit conductor as
  specified in Table 28.1 and Table 38.1.

  Exception No. 1: When the control circuit is tapped off a motor branch circuit protective device and the
  control wires do not leave the industrial control panel enclosure (such as when a start-stop button is
  provided on the enclosure cover) the motor branch circuit protective device provides the required
  overcurrent protection when its rating does not exceed that specified in Table 41.1.

Given that Table 41.1 in UL 508A-2014 permits a 14AWG control tap on a motor branch circuit of up to 100A in size and a 16AWG tap on a circuit up to 40A when the conditions of Exception 1 are met, I would say that the safety case for the potential tap wiring you see in your inverter works analogously to the logic behind the above quoted exception.


Best insulation system below a wood floor exposed to nature This area to be insulated is just past the wood deck. You can see chicken wire holding up the old batt insulation that is been torn down by various creatures!  The floor is supported by joists laying across the stone piers.

Considering spray foam but interested in something modular.

You can use foam boards (XPS or EPS). Cut these to the appropriate width, place in the joist bays, glue/screw as needed and fill in the gaps with canned spray foam. Those are fairly resistant to exposure within a crawlspace.

Consider sealing off access into the crawlspace if possible. You'll never keep all the insects out, but covering access holes with chicken wire or mesh will help keep raccoon or other scratching/digging animals out.


Install foreign outlet in my US home? I'm moving back to the States from Asia, and I have a lot of things I want to plug in that run on different shaped plugs. In Thailand, most new buildings are equipped with nifty outlets that can can take US, Euro, and Australian shaped devices.

I am not concerned about 110/220 conversion, as I know that anything I will be plugging can handle being plugged in anywhere worldwide. All I care about is the shape.

Could I purchase these outlets at a Thai hardware store and install them in my home in the US the same way as I might upgrade an existing outlet to one with USB (for example)?

Thanks for any input!

What I like to do is to buy a power-strip in the foreign country, then cut of its cord and replace it with a sturdy US-purchased plug.  That way you don't have to modify your house or your appliances, but also don't have to use those cheap travel adapters.

If you do still want to modify your house it probably will not be as easy as when you upgrade an outlet to have USB ports because the junction box is not the same size and doesn't have the right screw holes (at least the ones that I saw in Thailand and Myanmar were not the same, although there seemed to be a wide variety so maybe you could find one), but there are electrical outlets designed for exactly what you are trying to do and sold in the USA!  They are often installed in places like airports, and sometimes have the words "120v 60Hz" printed right on them.  One example is the Leviton 5825-W, which can't accept as many varieties as you mentioned, but at airports in the US I've seen outlets that accept Australian and even UK plugs.  I don't know the make or model number of those, but I guarantee the people building the US airports didn't buy them at a hardware store in Thailand :), so figuring out what brand those are would be better both because they match the junction box size and because they will comply with the US wiring codes (important both if you ever sell your house and if there is ever a fire at your house and the police or insurance company are investigating the cause).

(I realize that I'm responding to a question that is years old, but this page still comes up high on Google results, so hopefully this will be helpful to someone!)


Can I reduce the grinding and humming noise from my portable air con's compressor? My portable air conditioner's compressor can get quite noisy, it's like a vibrating pulsing grinding noise. Is it possible to reduce this noise?

Check to make sure one of the (presumably plastic) panels that make up the exterior of the unit are not loose. My unit had a "fancy" black plastic border that fastened around the front panel, and it would over time begin to work loose as the compressor vibrated. I ended up wedging a little folded piece of paper between the front panel and the bordering plastic to get it to shut up.

Other than that, put something vibration-absorbing under it if possible, as Ed Beal suggests. There's not a lot to be done. These units are noisy because the usual outdoor bits are now in a box next to you. But if you need cool air, you need cool air!


Ceramic tiles on concrete walls Can I put ceramic tiles right on my poured basement walls ?  I want to put a shower in and tile the walls floor and cieling. Should I put a false wall and tile over it or can I put ceramic right on the concrete?

You can definitely put tiles right on the concrete wall. However, if you're building a shower, it's critically important that you have a waterproof membrane separating the finish materials (tile) from the structure (concrete walls and cement backboard on any framed walls you build). I suggest painting the walls with Redgard, a sort of paintable rubber. You paint the floor, too. Then you tile over that.


Extension cord and power strip safety I've heard that there are some safety and building code issues involved with using extension cords or power strips (surge protectors) for anything other than temporary use. What are the issues, and how can extension cords be used safely?

This is one of the biggest problem with power strips (surge protectors)...

Overload!

The average person does not think about how much power each device is drawing, or how much the system can handle, they just see an open outlet and plug stuff in.  If they can't find an open outlet... Oh yeah! they make adapters for that!  I mean they sell the adapters, so they must be safe... Right?

If your power strips look like this (or worse), you better at least be checking the batteries in that smoke alarm (which is hopefully not plugged into this power strip too).

If you are using the power strip (or extension cord) properly (one plug per outlet, no adapters, no daisy chaining) and you inspect the power strip for damage (wear & tear) regularly, you should not have much to fear.

Another thing to look at when using a power strip or extension cord, is the size of the wire and the voltage and amperage ratings.  If you are using things like electric heaters, power tools, vacuums, etc., make sure the wire (extension cord/power strip) is the proper size to handle the above average load of these types of devices. Overloaded wire can heat up quickly and cause a fire.

Basically if you use common sense, inspect the cables for obvious damage and/or wear & tear regularly, and use the cables for their intended purpose, you should have no problems using extension cords and/or power strips.

Here is some interesting stuff from The Office of Compliance about
Power Strips and Dangerous Daisy Chains.

  Problems:

  OSHA regulations require that conductors  and  electrical  equipment
  be  used  in  accordance with the conditions under which  they are
  approved by a recognized testing  organization (29 CFR 1910.303(a)).
  Most  power strips are approved for providing power to a maximum of four or
  six individual items;  however,  when  multiple  power  strips  are
  interconnected, the one directly connected  to  the  building  outlet
  is  often  supplying  power  to  far  more  than  the  approved
  number. This electrical current overload can  result in a fire or can
  cause a circuit breaker  to  trip, deenergizing computers and other
  equipment throughout the area. The risk is  magnified when another
  outlet in the same  wall or floor receptacle is also overloaded in  a
  similar fashion.  When other outlets on  the same circuit are also
  overloaded, the risk  increases.

  Extension  cords  are  sometimes  used  to
  energize  power  strips  in  locations  far
  from outlets.  Because electrical resistance
  increases with increased power cord length,
  interconnecting  cords  increases  the  total
  resistance  and  resultant  heat  generation.
  This creates an additional risk of equipment
  failure and fire, particularly when paper and
  other combustible materials are in contact
  with  the  wires.  Additionally,  OSHA’s
  regulations allow extension cords to be used
  only as temporary wiring for up to 90 days.
  Unfortunately,once in place, extension cords
  tend to become permanent wiring and a fire
  hazard.

  Solutions:

  Several safe solutions exist.  In many cases, a
  power strip energized by an extension cord or
  another power strip can simply be replaced by
  a power strip with a power cord of adequate
  length to reach an outlet.  Other
  times, use of a power strip that is better able
  to accommodate bulkier transformer plugs
  solves the problem.
  Several factors should be considered when
  selecting an appropriate surge protector. Since
  models vary in the amount of current that
  they are rated to safely carry, it is important
  to consider  the amperage  requirements of
  the devices to be energized. Models vary in
  length of power cord, typically ranging from
  three to 15 feet. Choose one whose length is
  most appropriate for reaching the intended
  room outlet. Avoid having too much excess
  cord, and make sure the surge protector is set
  on its base. Some have swivel plugs which
  makes them easier to connect to the outlet,
  and helps to protect the plug and cord from
  damage.  Check  each  surge  protector  to
  make sure it is in good condition for use.

  Only power strips equipped with internal fuses are acceptable as permanent wiring.  Those
  lacking  these  fuses are equivalent to extension cords, and  therefore may not be used as
  permanent wiring.  When a power strip is installed, care must be taken to ensure that it is
  not suspended in mid-air by its power cord or cords plugged into it, resulting in excessive
  stress on electrical connections.

The National Electrical Code (NEC) has a whole article devoted to flexible cords and cables, one of the more applicable sections in this case would be 400.8.

  2008 National Electrical Code

  ARTICLE 400 Flexible Cords and Cables

  400.8 Uses Not Permitted. Unless specifically permitted in 400.7, flexible cords and cables shall not be used for the following:
  (1) As a substitute for the fixed wiring of a structure
  (2) Where run through holes in walls, structural ceilings, suspended ceilings, dropped ceilings, or floors
  (3) Where run through doorways, windows, or similar openings
  (4) Where attached to building surfaces
  *Exception to (4): Flexible cord and cable shall be permitted to be attached to building surfaces in accordance with the provisions of 368.56(B)**
  (5) Where concealed by walls, floors, or ceilings or located above suspended or dropped ceilings
  (6) Where installed in raceways, except as otherwise permitted in this Code
  (7) Where subject to physical damage

  *368.56(B) Cord and Cable Assemblies. Suitable cord and cable assemblies approved for extra-hard usage or hard usage and listed bus drop cable shall be permitted as branches from busways for the connection of portable equipment or the connection of stationary equipment to facilitate their interchange in accordance with 400.7 and 400.8 and the following conditions:
  (1) The cord or cable shall be attached to the building by an approved means.
  (2) The length of the cord or cable from a busway plug-in device to a suitable tension take-up support device shall not exceed 1.8 m (6 ft).
  (3) The cord and cable shall be installed as a vertical riser from the tension take-up support device to the equipment served.
  (4) Strain relief cable grips shall be provided for the cord or cable at the busway plug-in device and equipment terminations.

400.8(1) As a substitute for the fixed wiring of a structure.

400.8(2) Where run through holes in walls, structural ceilings, suspended ceilings, dropped ceilings, or floors.

400.8(3) Where run through doorways, windows, or similar openings.

400.8(4) Where attached to building surfaces.

400.8(5) Where concealed by walls, floors, or ceilings or located above suspended or dropped ceilings.

400.8(6)  Where installed in raceways, except as otherwise permitted in this Code

400.8(7) Where subject to physical damage


Does ambient temperature impact gas pipe sizing? I'm running a gas line for a garage heater in a cold northern climate. At times the pipe could pass through air as cold as 0°F.
Does pressure drop due to reduced pipe temperature present a concern with respect to pipe size, or will the supply pressure compensate? In other words, would pipe size need to be increased to provide additional storage volume?

The child's balloon is a great analogy for the gas piping system in a house. But rather than having been tied off with a knot, the neck of the balloon is still pressed to the lips of a parent with infinitely large lung capacity. (The gas piping is not a closed vessel, but is connected through the gas meter to a vast reserve of natural gas in the supplier's distribution system.) If the parent steps outdoors into a cold ambient, using their diaphragm to maintain steady air pressure inside the balloon, the balloon won't shrink. It's true the air inside the balloon will contract -- it'll become more dense as it cools -- but some of the infinite supply of air in the lungs will flow in to make up the difference and maintain the volume or size of the balloon.
What would happen if the child's balloon were not a round globe, but instead a very long tubular balloon used for making art? If just the end of the balloon were put out through the window, would the outdoor part shrink while the indoor part remained unchanged?
Pressure in a closed gas pipe system, ie where the meter is hooked up but at the moment there's no flow, will be equal at every point in the system regardless of the temperatures of various sections. The density of the gas will vary with temperature but its pressure will not.
But static pressure is not the factor that causes us to use varying sizes of pipe.
When the appliance valve at the end of the pipe opens and gas starts flowing, then yes, the strict engineering answer is that ambient temperature affects the pressure drop. Engineer's Edge provides the following equation for calculating pressure drop of a fluid flowing in a circular pipe:

The relevant piece here is rho, the density of the fluid. The density of natural gas is inversely proportional to temperature; as the gas gets colder its density increases. Because rho is in the numerator, an increase of density caused by low temperature leads to increased pressure drop in the pipe. That could make necessary an increase of pipe size.
Fortunately, for small buildings matters like lumber, wire, and pipe sizing are often handled by following prescriptive tables rather than by developing site-specific engineered solutions. Though the pipe sizing tables don't explicitly state it, I believe we are to assume that the prescriptive tables include allowances for worst-case conditions of cold temperatures, rough and rusty pipe walls, and so on.


Dimmer switch replacing 3-wire switch not working I need some help to get my dimmer switch working with my light. I have power coming into the junction box and then leaving to go to a second outlet and the light. The original light was a 3-wired light with a fan, but the new light is just a light, no fan.

How do my wires need to be connected to make this happen? Both outlets continue to work just fine, but I can't get the switch to work with the lights. The dimmer is a Lutron 600w dimmer. Thanks.

Your original is not a 3 wire light, but what amounts to a fan with a light kit installed.

2 wires are for the light and one for the fan.

Generally they are wired WHITE - NEUTRAL to [FAN / LIGHT] , BLACK - HOT for [LIGHT] . RED - HOT for FAN.

Is there another Switch on a different wall same wall that operated the original  Fan/Light Combination?

This would tell us that the RED is a Traveler for a 3 Way Switch.

You will need to provide some more details:

Measure voltage between Copper Wire [GND] and WHITE.
Measure voltage between Copper Wire [GND] and BLACK.
Measure voltage between Copper Wire [GND] and RED.


Can I clean range hood exhaust duct without reaching it? My home range hood is Sakura R-727II. Plz see pictures that post. I never clean my range hood's EXHAUST DUCT 7 years after buying. It's probably greasy and clogged.
How can I clean it, but not access it? I don't want remove range hood or open exhaust duct. I see no Access Panel like picture below.
Are there safe chemicals I can spray at range hood? Then when I turn on range hood fans, these chemicals suck into exhaust duct, destroy grease?

Exhaust duct is greasy clogged, right?  - We do not know, we can not see it from here.

How can I clean it, but not access it? - You can not. You have to access the duct if you want to clean it.

Are there safe chemicals I can spray at range hood fans? - There are dozens of safe grease cutting/cleaning chemicals on the market.

Then when I turn on range hood fans, these chemicals suck into exhaust duct, destroy all grease, and everything sucked out? - NO, that is not how it works. There is no sucking mechanism in your duct.

I don't want remove range hood or open exhaust duct. - Sorry but removal of the hood is required to clean the duct ( and to even assess if it is indeed full of grease.)

Here is the USA distributors web site. Your model is the R-727II.

Here is the contact email for sakura USA -  achoo@sakura-usa.com

Here is  link to  a search results on YouTube for cleaning range hoods.

Your unit does appear to be rather unconventional, looking at the photo it is not clear where the filters are or how to access them.

That is why you need to contact them directly.

UPDATE: Your range hood does not have "traditional" screens that trap the grease. There are two clear plastic grease collectors for each fan. one is mounted to the cone shaped fan guard and the other is at the back of the unit behind each fan near the wall. I believe the premise is condenses or collects on some unknown to me part of the unit and then drips down into the removable plastic receptacles. In theory the grease should not be getting into your duct. this video, not in English shows a brief simulation of the grease trap at work near the end of the video. Here is link to a parts page that has the plastic trays.

Please send me your gratitude in the form of a quality local craft beer from the area of your region. thanks.


HVAC tripping breaker - things to check before replacing? HVAC system (we're in Houston, it's still hot here) stopped working Tuesday.  A/C guy came out, determined it was tripping breaker.  Would trip immediately after resetting, but after a couple of resets would stay on for a few hours.  Suggested we replace breaker.

I replaced the breaker.  Same problem.  A/C guy some back, swears that everything is good on the A/C side.  Capacitors look good.  Now it trips every time and won't stay on at all.

Electrician comes out.  Examines breaker and panel, says it looks OK.  Replaces line from panel to A/C just in case.  Still trips every time.  Electrician swears it must be a problem on the A/C side.

A/C guy refuses to come out a third time.

I disconnect the fan in the A/C - breaker still trips.  Then I disconnected the leads to the compressor - now the fan will come on.  So it seems like the compressor, or something in that chain, is causing the issue.

We have a different A/C guy coming tomorrow to look at it.  I have a feeling they are going to say we need to replace it.  I'm not sure how old the unit is - probably 10+ years, which seems too soon to replace to me.  But that might be the best solution.

However, I want to be sure that we aren't doing this prematurely.  What else can I check, or ask the A/C guy to check, that might be a cheaper/easier fix than replacing the entire system?

FWIW, we have an upstairs and downstairs unit.  The busted one is downstairs.  The slightly smaller upstairs unit is OK.

The condition you describe is usually an indication that the compressor is unable to provide sufficient start torque to turn without drawing excessive amperage. This is frequently due to a weak run capacitor on the compressor.  Less frequently this can be caused by a contactor in poor condition or an old compressor where the bearings have worn to the point that the unit requires higher starting torque than normal.  Given what you have already eliminated, the cure to this problem is very likely to be one of, or a combination of, the following:

The run capacitor for the compressor is weak (most likely).  This cannot be determined by visual inspection.   If not already checked with a meter, then disconnect the capacitor and measure it with a capacitance meter (the main disconnect must be OFF).  If less than 90% of the labeled value, then it must be replaced.  Multi-meters with a capacitance scale are less than $20 from Amazon and others.
The contacts on the compressor contactor are badly pitted.  This can cause a high resistance connection in the contactor.  Visually inspect the compressor contactor for any signs of heat damage.  If possible (with the main power off), remove the arc-shield and inspect the contacts for pitting.  If there are many deep pits (greater than 1/32"), then the contactor must be replaced.
The compressor is a bit worn.  To provide the increased starting torque necessary, install a "hard-start" kit for the correct horsepower unit that you have (roughly, your compressor motor will be 1 HP for each 12000 BTU cooling capacity).  I prefer the 3-wire type of hard-start kit because it is more stout, although these are more difficult to find online than the 2-wire type.  The 3-wire kits are readily available at A/C supply houses and perhaps your next technician can help you with this.  If this is the problem then your unit may be on its way out; however, compressors can run many additional years with the correct hard start kit installed.
Install a 3-5 min "delay on make" on the compressor contactor coil (a $10 part).  If you install a 2-wire hard start kit, it is mandatory that you also have a 5 minute delay installed.  (Note that if you cycle the breaker for the compressor while unit is running, the delay on make will not be triggered and you may still trip the breaker with this action).


Do I need to use cripple studs if header is tight to the top plate? So I am placing a 13ft LVL Header beam, in a load bearing wall, to place a Patio Door.

I am using a 3-1/2 by 11-7/8 Versa-Lam LVL beam, as recommended by my Engineer.

I am planning to place the top of the beam tight to the bottom of the plate above, leaving no room for a Cripple stud.

Is this not acceptable? Or do I have to have Cripple Studs between the beam and the top plate?

Thank you.

No crippling required in cases where there is no room for them


Is it safe to use “PushFit” fitting on gas pipes? There are many makes of pushfit pipe fittings that make it a lot easer to join pipes, incluing copper pipes, e,g:

John Guest Speedfit
Cuprofit®- copper push fit
Hepworth-HEP20

Are they safe to use on gas?

In the UK, it's not legal (quite correctly, in my view) for householders to work on gas pipework or fittings at all.

If a buildings inspector or surveyor spots pushfit fittings on gas you can expect plenty of trouble down the line... to say nothing of the risk of a pinhole leak or if there's another fire nearby that melts the fitting.

While you might save a few pounds in the short term, do you want to risk your life and that of those around you? A leaky joint in a water pipe might wreck a ceiling or a floor, the same in a gas pipe might kill you.

Head here for details of the Gas Safety scheme which holds a register of tradespeople who can do the work for you.


How to fix the Sputtering faucets in bathroom with air locked in pipes The hot water faucet is Sputtering heavily. I tried opening up all faucets in the house and let the water run for more than 10 minutes, but the Sputtering continues. This is in the upper level bathroom and only the hot water faucet is Sputtering.

Movement in the hot water supply line below the sink may be touching the shutoff valve thus creating a resonant effect. Try partially closing the hot water shutoff valve to determine if it's modified angle stops the sputtering.
If this stops the sputtering, dampen movement in the hot water supply line or block anything that could touch the shutoff valve when it's completely open.


Opening in dropped ceiling causes room to get warm I've moved into a new home last year. One attached room is a workshop with a drop ceiling and it was comfortable at around 70 degrees last summer with the air conditioning. This year, I moved a piece of equipment in there and had to removed a section of the ceiling to accommodate the equipment height as it's about three inches higher. I now have one to two feet of open space around the equipment.

It got into the 80s yesterday and the room got quite warm, about 75F. I assume it was because I removed part of the ceiling which lets the much warmer air above it to filter down to some extent.

I'm trying to find something to put over the space in the ceiling. I can't build anything permanent cause I need access to the top of that on occasion. I'm thinking I could make a light frame of sorts that could lay up there but what would I put in it to keep it easily movable and not too awkward? I can't just throw insulation up there cause I can't worry about fibers from that.

Or is there a better idea? Of course, I don't want this to be expensive either.

Without more information or a photo, my answer is to purchase a replacement ceiling tile, cut it to fill your gaps, put the original tile you removed in storage so you will have it if you move out of the space.


Samsung Front Load Gas Dryer, plastic connection problem RE: Samsung Front Load Gas Dryer. DV42H5200GW. T
his should have been an easy install, but plastic gas fitting seems to have cracked. I was just connecting my existing gas line to the dryer, and I may have over tightened the fitting as I heard a slight crack or squeak and now the plastic fitting on dryer is turning as I turn the line fitting. I will now remove the back panel to investigate, but I cannot afford to hire a pro.

It's possible that the plastic part is intended to spin like a female garden hose end does. To check for leaks, drizzle soapy water over the connection. Without photos or a better description of the problem I can't say much more.


Are there other advantages to using turf over grass seed besides getting instant results? As I mentioned in a previous post, I'm planning to eventually have a lawn in our front yard (right now, it's bare due to septic work).  I'm confused on if there are clear advantages to using turf vs just planting the seed.

As far as I can tell, the only major difference is time.  Am I missing something here?

I've looked at this in the past.  These two links are pretty general, but each has an interesting tidbit.

Link 1 "If your yard has especially shady spots, you might be better off seeding those areas, since most sod is made up of sun-thirsty grass varieties."

Link 2 "A prime disadvantage of sod is the limited number of grass species included in sod mixes."

Other than that, sod is a clear winner if you have more money than time.  I've done both, killed both, and revived both...lets just say I'm eyeing my neighbor's lovely rock garden with a bit of envy.


Powering Freezers with small generators I have a small 230v 650VA generator capable of producing generating 450w. I also have a deep freezer rated at 230v 110w running power. I feel the reason why the generator doesnt power the deep freezer is because of the huge startup wattage required by the freezer.
So I am considering using the generator to power a 12v 15amp battery charger which charges a 12v 40ah battery connected to a 1.5Kva inverter which powers the freezer.
My assumption is that the Inverter-battery combo will handle the startup surge which lasts a few seconds while generator-charger combo handles continous charging of the battery while the freezer runs.
My question to the house is will this work? Is it efficient? What other ways are there to optimise the set-up?

thanks

A 12V generator would be more efficient than a 230V generator running a charger.

eg; a small engine driving a re-purposed automotive altenator


Mount glass shower wall with adhesive to avoid drilling holes in the bathroom tiles I would like to mount a glass shower wall in the bathroom but avoid having to drill holes.
The model in question is the following: http://www.bathdeluxe.com/products/130/130-328-toscana-wall-manual.pdf
As you can see it requires 4 screws to affix it but I would prefer to use an adhesive if there is anything that can be used in this situation.

I've been looking on different other somewhat similar questions and some of the suggestions were: Kerdi-Fix / Plumbers Goop. Since I have never used any of these I would like to ask if either of these are good for this purpose or if there is any other known method to achieve what I desire.

LE: I have stumbled upon an adhesive that seems to be very powerful but I would love to get a second opinion on it so I am linking to the product sheet: http://www.bostik.se/downloads/datasheet.ashx?p=P0703&l=EN

Regards,
Ovi

Since the answer was requested in other comments to be added to the initial post, the solution that was sent by the manufacturer and actually fits my requirement is a special "Glue kit" they sell for exactly this type of requests. The product was linked in another comment in case anyone is looking for something like this (there is no term I could use that people could just search for and find the right thing)

Thank you for the answers guys but I actually asked the manufacturer if they have any suggestions and they came with the best solution ever :D

Apparently there is a kit available. I am not sure how one would search for this as the manufacturer sells this "glue kit" especially for this type of situations. I am not sure if this is something you can find anywhere but for reference here is the actual product.

I have not mounted it yet but once it arrives and I do the work I will try to provide more details about it.


How long should it take to a 1.5 tons AC to cool down a 2000sqf house from 80F to 77F? I know that it might depend on a lot of things like:
-how air tight is the house
-how old it is (insulation, windows etc)
-what windows are installed -BTW I have casement window
-outdoor temp (currently 86F)

Please just give me a rough estimate or ask me more questions to narrow down the posibilities
The house is more like 1900 sqf actually and downstairs is colder... 75F

Here are the settings that I received from HomeDepot at my request
This is a Trane XR16-018 (not sure about the last three digits)

As written this question is pretty hard to answer.  It sounds like you're having AC problems tho and need a test method.

Find or purchase 2 probe type thermometers like thermometers. Analog or digital doesn't matter, the only things that are important are that they have a probe and that they give the same reading laying next to each other on a table (you will be surprised how many don't).  You can purchase these many places for under $10, there normally used in the kitchen.

Take these to the area of your furnace and find someplace to stick each in, one in the return air, one in the supply air.  There is always a crack or hole in the ductwork somewhere, I have yet to see a case where a hole needed to be made.  On the return air side, the simple place is where the air filter is located. The supply side is harder to find sometimes, but just get the probe into the airflow.

Once the system has been running 15-20 minutes the thermometer should be reading temps about 15-20 degree's difference.

If your aren't getting 15-20 degrees of cooling you may need a service man, but check the filters first, and check airflow on the outside coils as well.  They typically need to be hosed off once or twice a year.


Correctly dealing with crumbling basement walls I have an older home with stone foundation and some type of crumbling lath covering it.  After doing some rearranging in my basement I cleared a wall which I'm going to put shelves against.  Before doing so, I had to remove a large pile of debris from the crumbling wall.  Is there a way to repair this to prevent future debris from accumulating? I'm sure a skim coat of something would be the answer.  I'm just not sure what to use.  Morter?  structolite?

Is there a way to repair this...

It's a lath and plaster wall, probably on furring strips. Remove anything that's lose and patch the holes with easy-sand or durabond (chemically setting). If it's bad enough the plaster might need to all come off and then drywall it, unless you can raise someone from the dead who can actually do plaster.

... to prevent future debris from accumulating?

That's the hard part about money pits. Intentionally removing any other lose plaster will give you more time until you'll need to do it again. But that's a band-aid on a foundation issue: water ingress.

But you patching the walls every decade is a lot cheaper than having drain tile installed around the outside perimeter of your house, and if you have a relatively dry basement with no flooding or seepage issues; not really worth it. Just make sure the grade is away from the house, and keep your gutters clean.

The other, somewhat excessive, option is to tear it all off and parge coat the foundation with the appropriate mortar. If the seepage problem is minimal, that should last the rest of your life. Again, you'd need someone who knows how to trowel, or it will look like a parge coat.

A picture might help, but I wouldn't be able to feel how lose all the plaster is. Use your best judgment. If large parts of the wall flex in the slightest, it should probably all come down. But it's a basement, maybe you don't really care; then patch and paint it with whatever (chemically sets). But when parts start falling off while you drag a paint roller over it, you know what you should have done.


What can I do about a toilet flange that is 1/4" below the floor My toilet leaks after i flush and doesn't seal properly at all…tried different kind of wax rings and aaah .. no solution ..cause leak and damage to downstairs ceiling ..better said it leaks and the elbow joint , if that helps

I have used rise-a-ring in the past a plastic spacer that brings the flange up to the new floor level after adding tile.


Gravel inside concrete form or form on top of gravel? I am pouring a 5 inch concrete pad for a hot tub.  I am planning on putting down 4 inches of compacted gravel under the concrete with rebar mesh in the center.  My concrete pad will be 9 feet by 9 feet.  Should I clear an area a few inches larger than 9 feet and compact the stone and place the form on top of that for my concrete (5 inch tall form) or should I use a 9 inch tall form and compact the stone inside the form and pour the concrete on top?  I have seen a few videos of it done both ways and I was wondering which was better.  Thanks.

The problem with just pouring a flat slab is the rock can migrate out if above grade. If this pad base will be at grade or below so the rock can not migrate it will be fine to leave it flat. If you are adding the rock on top of grade make it a monolith pour so the outside edge goes down to grade this also creates the footing I usually add.
If I think a Gazebo or a roof may be added I will create a small footing trench (an additional 4x4” deep/wide ) so the pad edge could support a small structure on the perimeter.
As a patio you are going well beyond what would be needed at 5” thick reenforced but I would still add a thicker perimeter edge just in case.
You don’t have to make the pad wider to do this just don’t fill the gravel all the way to the form to make the footing.


Running ethernet cable between drywall and cement foundation, and repairing drywall afterwards I am installing a new floor in a basement addition (addition was done sometime in the 2000s), and as part of that, wanted to run ethernet cables as well.  The floor is going to be 1" of EPS foam, and then two layers of 15/32 plywood.  I'm using the guidelines provided by the BuildingScience corporation.  Unfortunately, the ceiling is finished, and I'm not going to be able to replace it for the next few years, so I was planning on running 3/4" ENT conduit underneath the plywood against the walls, and fishing ethernet through there.  There are, for reasons I'm unclear on, several boxes already installed with no wiring going to them, so I figured I could just fish the cables up from the conduit.

So I was cutting through the drywall along the base of the wall so I'd have a path, and discovered not the plywood that I was expecting, but concrete.  I'm not sure if that's the foundation of the original house, or what.  And while I could in theory cut into it, I don't know of any reason to do so.  Instead, I'm planning on just running the ethernet up a channel from the floor (I'll install a low profile box under the new floor, instead of in the wall as I was planning to before).

So, questions are:  1)  Is this a horrible idea, for some reason that's not occurring to me?

2)  After running the cables, how do I patch the channel in the wall?  I won't be able to use a drywall patch, as the patch would be too thick.  I'm thinking about taking a piece of drywall of the appropriate size, shaving down the gypsum, and attaching it using the hammock method.

It’s not a horrible idea and should be fine.
if it was power you would need a nail plate over the wire but data doesn’t even need an electrical box.

I usually purchase metal rings that hold the cover plate , you will find most cable installed this way where they punch a hole through the wall, go inside find the hole and cut the opening slip the plate in , much easier than trying to fish the cable through a hole in the old work box.

These devices are called drywall brackets, mud rings, low voltage mounting brackets. Some are metal some are plastic they range in price from .50 to ~6$

I bought a case a while back of single gang sw-wbf-1 they were maybe .30 in bulk (100 count) some come with screws some don’t but drywall screws work just fine to anchor them in the Sheetrock.

You may want to cut a small Chanel in the Sheetrock to allow enough space for the wire as it looks like it is attached directly to the foundation.


Is this fluorescent light fixture a major electrical problem / fire hazard? (I am a new homeowner.)

I went to replace a some fluorescent tubes that looked like they burned out, but after disassembling it a little to get the tubes out, I saw something a little alarming:

There was a black sticky substance on the inside cover of the housing:

Picture #1 of what looks like a "burned" wire and "melted" electrical tape

Picture #2 of the same

Closeup of the "melted" electrical tape:

So, my questions are:

What happened here?
Were things about to catch fire?
Now that the fluorescent tubes are out is it safe, since the circuit is not complete?
Is this something I can fix, keeping in mind that I have no experience with anything electrical?  If so, how do I fix it?

EDIT:

The electrical tape was not melted, and the wire was not burned.  The culprit was indeed the ballast.  Here are the leaks:

Thanks, lqlarry!

You didn't show the ballast, (the black boxy thing with all the wires coming out of it in the fixture) so my guess is that it went bad and some of the potting insulation around the coils of the ballast over heated and melted.  (Since I cannot see the whole fixture I'm just guessing about that.)  It looks like the black on the cover is a tar type residue but I really would not touch it.  It is sticky and a mess to get off.
I doubt anything was catching fire, but when it happened there would have be smoke and a really stinky smell.  If you smell the ballast you will see what I mean.  But back to the fire, I'm sure this has caused fires in a very few cases.
I would disconnect the power or turn the switch off.  The ballast has a thermal cut-off that would probably de-energize the ballast, but it still has power.
It can be fixed, but for a DIY'er it is easier to change the whole fixture.  To fix it you would have to wire in a new ballast and that would be 8 wires, where a new fixture would be only 3, a hot, neutral and ground.

If you do it yourself, make sure you turn the breaker off before taking the old fixture out.  Out of the ceiling will be either a black or red, a white and a green ground.  A new fixture would show you exactly where to put the wires.  If you have a friend that knows how to do this then get your friend to show you how so you can see what it takes.


How much usable air in an air compressor? I'm trying to figure out how long a small 3 Gallon compressor tank will last in between the compressor kicking on and off. I know the tank volume, and cut-in/cut-out PSI, and my approximate SCF usage per minute. So can I just calculate the SCF of the tank at the cut-in and cut-out pressure, and then subtract them to get "usable SCF"?

The cut-in/cut-out pressure are the tank pressure before the regulator, which will step the pressure down 40-100 PSI. But converting to SCF should accommodate for this, right?

I'm using SCF = ACF * (tank pressure + 14.7) / 14.7 (in cubic feet and PSI units), where ACF is the actual tank volume.

Then the "usable air" = SCF_cutout - SCF_cutin?

EDIT: Concrete example:
Tank: 3 Gallons = 0.4 cubic feet (ACF)
Compressor Cut-out: 150 PSI
Compressor Cut-in: 120 PSI

Tank SCF @ 150 PSI: 4.5 cubic feet
Tank SCF @ 120 PSI: 3.7 cubic feet
"Usable SCF" = 4.5 - 3.7 = 0.8 cubic feet      <-- is this correct?

RE: regulator pressure, it will be between 20-80 PSI - but the conversion to SCF should account for that, no?

Long story short, if I'm using 2.0 SCF/minute constantly, with only 0.8 SCF available in the tank between compressor cycles, then the compressor will always be on, which is bad, right?

[all this is ignoring temperature for simplicity, which I acknowledge is unrealistic]

You should just measure the usage time through real world experimentation. This will give you the quickest and most accurate information at your real world set of conditions.

Empirical measurement methods will factor in all the variables of the system that may not be considered in a simple theoretical mathematical model. In fact the empirical method would be used repeatedly to verify any mathematical model while all the unaccounted variables are factored into the model.

If you do not currently have the air compressor unit on hand to do the empirical test you should consider one of:

See if you can borrow a similar compressor from a friend or colleague. It may be even easier to take your attachment gear with you to their shop or garage to do the test since for a test on a 3 gallon tank it will not take a long time at all.
Rent a unit from a rental yard for a half day. Schedule it so you can use it when you can also plan to use it for a regular task.
Take your gear with you to the orange colored BigBox store....many have rental sections....and explain that you are looking to purchase a unit from the store and ask them if they would help you run the empirical test right there in the store.


Will a Broan 750 fit in the same cutout as a NuTone 8664RP? I would like to replace a 'disappointing' bathroom ceiling exhaust fan with some other brand, but have the challenge of predicting what is compatible with the existing drywall cutout. Few online manuals tell the cutout size - they just say to use the template or the housing to mark the cutout required)

It's a round fan/light (NuTone 8664RP) with 13-1/4" circular ceiling drywall cutout, and a 15" grille. May be same as Broan 750, but the Broan manual implies using the housing to draw the opening required, while the NuTone specs do call out 13-1/4" opening. I compare them just for reference. Broan & NuTone are part of the same company. The Broan one has a night light.

Basically, what I'm asking is whether anyone else has done this. Online reviews clearly show unhappiness with the 8664RP performance, so maybe someone found a solution.

I haven't worked with these exact units but they should have pretty similar requirements. I was able to find a diagram on the Broan website for the 750 that allowed me to extrapolate the size of the cutout.

Bear in mind there's a bit of margin for error in this trick but as you can see, the diameter of the cutout would be roughly 13 1/2". You may have to ream out your drywall a bit but that's better than having a hole that's too big. And remember your grill is 15" so you'll have aprx. 3/4" of fudge room all around. In all likelihood the drywall cutout won't be an issue, but you'll probably have to modify the blocking to accept the new unit, which (as long as your framing is as it should be) won't be too much hassle.


New 220V outlet for expansion? I'm adding onto a 220v circuit that I installed a few years ago.  I knew I would likely want a 220v outlet in my garage, the current circuit runs 4AWG to a spot 5' from the garage wall.  It currently runs a mini oven/range in my guest kitchen (30A).

The immediate needed in my garage is a 5A rated electric motor, but I want to be able use it for a 50A welder that I1  might buy in the future.

Since there are numerous 220v, generally differing in amp ratings, I'm not sure what to use for the new outlet/plug.  Do I use a low amp plug & outlet now and add another high amp outlet whenever I get a welder?  Do I install a 50A outlet and plug now and be done?

Also, the circuits breaker is currently rated for the 30A range load.  I assume the full 30A would only be used if all 4 burners and the oven were heating simultaneously. (Probably never has been done since I installed it 10 yrs ago)   Are there any safety issues with keeping the 30A breaker, or do I need to install a 35A one immediately?

FWIW, my property is not legally required to follow code, but safety is a high priority.  I follow code unless there is an edge case where code makes no sense.

The motor's nameplate specs:

You should wire in a sub-panel at/near the "guest kitchen" (current terminus of the 4Ga wire.)

That sub-panel would be where you move the present 30A breaker to, for the outlet feeding the stove (only.) You feed that sub-panel with a breaker suited for the wires feeding it (copper being higher than aluminum for the same size) and the temperature rating of the wire insulation or terminals (whichever is lower rules.)

The sub-panel should have adequate space for the 30A breaker for the stove,  a 15A breaker (circuit for your 5A motor) and a 50A breaker (circuit for your 50A welder.)


What is causing this ghost flush? I have an American Standard toilet, with interior pieces that look pretty new.  The toilet suffers from a ghost flush, roughly every fifteen minutes the water kicks on for a few seconds to fill the tank.

The flapper (part that lifts when the toilet is flushed) does not have a gasket to replace, and seems new (is clean).  It does have a dial I can turn on it, though I'm not sure what that is supposed to do.

Is there anything else I should check that could be causing my toilet to run intermittently?

May look new but the flapper is probably leaking. Put a few drops of food dye in the tank then keep an eye on the bowl and see if the color migrates to the bowl. If it does then the flapper is leaking.


Room by room finish after electrical rough-in? We've just had our house (renovation project) re-wired with a first fix. There are two ring circuits for the sockets - one for the front room and one for the rest of the house and a lighting circuit.

Unfortunately, we do not have the time or the money to decorate all of the rooms in one go. We're going to try and do up one room at a time. Is there anyway we can restore electricity to individual rooms that are part of a larger circuit?

Example: The main bedroom has 4 sockets and a light fitting. Can we attach all of the fittings in this room and turn on the upstairs circuit, simply temporarily taping over the exposed wires for the rest of that circuit (we'll turn the power off again when we go to decorate the other rooms).

In essence, we are renovating on a room by room basis, but one circuit covers several rooms of the house at once. Can we restore electricity to one refurbished room whilst still having several rooms with just 'first fixed'.

Thanks!

Is it possible to pull a few new circuits? Many older homes were wired similar to yours. Breaking out the bathrooms and kitchen electrical to there own circuit is one of the things I used to do when remodeling. If I understand your question you want to remove the outlets and light fixtures.  Then use tape to protect the exposed wires. This may work depending on how the outlets are wired. If the outlets are pig tailed so only one set of wires go to the outlets or fixture your plan will work fine. If there are multiple sets of wires going to the outlets or fixture these will need to be combined using a wire nut or splicing device legal in your area. By adding 1 short piece of wire to the splice re-connecting the outlets will be easier and a piece of tape on the end of the short wire will work the same on your new pig tail to protect the live wire.

Added from comment as requested:You can do 1 room at a time. The "ring circuits" this means one outlet feeds another. These will need to be pig tailed as described above so all the circuits will work then the order you do the rooms wont matter. If you start at the first room with power make sure to tape all the Hot wires because when you energize the first room the wires going to the second will be live. but both methods will work.


How can I build my own deck canopy? I'd like to build my own deck canopy, and not purchase those retractable awnings that don't seem to last so well out here in Colorado (can be very windy).

I have the 'basic' idea in my head but are there any good resource or plans for building a proper, safe, reliable deck canopy?

Edit: I was thinking two posts to connect to my existing deck posts.  Our deck is raised.  Then a header piece at the front of the deck, connected to the posts to which I would take a runner board for each side and connect that to the house.  I want to use a retractable awning.  Does this make some sense?

I like this idea: http://www.diynetwork.com/how-to/how-to-build-a-shade-canopy-frame-to-a-deck/index.html

Without knowing what's in your head, I'd say start with some basic deck pergola designs, and modify them to accommodate the canopy style you're envisioning.

Basic pergola for a deck instructions


Need the name of a small pin used as a cheap door hinge What is the name of this pin?
I have a cheap piece of furniture where two of these pins are used as hinges: one side goes in to the frame and one side goes in to the door. I lost one of the pins and I can't find the name of it to buy another one.

If it's 5mm in diameter, it's a common shelf pin / shelf support.


What is the proper setback from the curb for a mailbox? I seem to recall my mailbox having instructions on what the proper setback was from the curb for mounting it.  Unfortunately, I was too lazy to re-set  the post for the mounting hardware after the snowplow took out my mailbox last year, and didn't want to move the post even though the hardware was different, and I remember that the instructions gave a setback, which I was technically not complying with (as the new mailbox had different mounting hardware).

As I can see from looking out the window that my mailbox got taken out again this year ... at what distance should I have it from the front of the curb?  (and I'm in the U.S.)

(UFPI says a "must be at least 8 to 12 inches away from the curb of the street"; Answers.com claims 6-9 inches; eHow claims 6-8 inches)

6-8 inches from the curb according to the official USPS website.

Of course, this refers to the location of the door relative to the front face of the curb. If the plow is taking out the post, rather than the box itself, you could install a post that is angled, rather than vertical. My dad would cement a 6-foot steel fence post 5 feet into the ground in front of the mailbox post. "That'll show 'em!"


How do you release the wires from a push-in wire connector? I would like to reposition some pot lights - before drywalling the ceiling.  They have been wired using push-in wire connectors.  How do you release the wires from a push-in wire connector ??

If you're talking about an outlet - or a similar concept fixture - the best tool I've found is a flat head jeweler/precision screw driver.

The wire is being held in by this:

You can see you'll need to push that "tab" away from the wire, from the back of the outlet you should see a small rectangle hole next to each circular hole that the wires are in:

MAKE SURE POWER/BREAKER IS OFF YOU WILL BE TOUCHING A "LIVE" WIRE
Insert a small jeweler screwdriver in the rectangular hole/slot, use the box as your pivot point and the screwdriver as your level (bring back end of screwdriver towards wire to force "tab" away) and gently pull the wire out.

* If the outlet is old/weak or the wire wasn't inserted in deep you can sometimes get away with just twisting the wire back and forth while pulling.


Connect all 3 switches in a 3 gang to be controlled by a single switch? My kitchen has three light switches (1 main light, 2 under cabinet lights), all in a single box (3 gang). I want to connect them together so that a single switch turns them all on/off at once. Can I wire them as such easily?

Sure.

Just pigtail a short piece of wire to the three wires feeding the lights and terminate it on the switched terminal of the switch you want to control them.

Good luck and stay safe!


How to fix water damage to wooden table I have a wooden table, which I accidentally spilled water onto yesterday. I thought it would simply dry, but a couple of hours later I noticed that the water had pooled on the wood and the surface under the pool appeared discolored.

I dried it off and noticed that the gray discoloration was coming off, so I scrubbed all of the gray off, and afterward the color looked consistent. Unfortunately, a few hours later I found that the area under the pools now looks completely different from the rest of the table.

My guess is that I accidentally removed the stain from the wood. I know nothing about this topic though, so I wanted to ask the experts:

What do you think happened here? How can I fix it?
A picture of the current state of the table is attached.

Definitely looks like you pulled a surface finish off the wood. Either the original stain was a surface-stain, or the water and cleaning may have pulled the color out of a shallow penetrating stain.

You're best option for a quality finish is going to be stripping back the whole table and starting fresh.

Assuming that's not an option, you could try finding a similar color finish at the hardware/home store. If you know what kind of finish was used originally, you should match it. Wood finishing is as much an Art as a Science, so the usual warning apply, but in this case, an imperfect patch may be better than the bare wood.

Sand away the affected area and an inch or so around it, so you can feather in the patch. This kind of patch will never look perfect, but may be "good enough". Apply your stain with a brush or a clean rag, following the instructions on the container. The longer you leave the stain on the surface, the darker it will be. Once you feel it's matching, wipe away the excess stain. Stain is for color only, and won't provide any long term protection. You can apply stain in multiple passes.

After patching you can blend the patch a little by using one of the antique furniture restorers (Restor-a-Finish), which will also help the look of the rest of the table. Just make sure to wait several days, or you'll pull the new patch out of the wood.

As a note. You can try an all-in-one stain+finish, but these products don't always work, and controlling the color can be difficult. In this case, you may want to skip the actual protective finish coat, and just try to stain it to match.

As always, try out any finishing on a less noticeable area first, like the inside of a face frame or drawer.


Ground-level electrical wiring to shed outdoors possible? I was telling an uncle about the concern of digging a conduit trench in my heavily planted garden (trying not to disturb the plants) to run electricity from the house to the shed about 35 feet away.

He said that you could run conduit on the ground (or barely cover it with mulch); no need to dig a trench and bury it. I am highly skeptical as I've never heard of this before nor can I find anything on it. He's done habitat houses.

Can you? I live in the US, Nebraska. It gets very hot and cold here seasonally.
Any tips on making a trench with a tight space?

With rigid or intermediate metal conduit ($$) you can follow code without going very deep - 6" under dirt, 4" under a concrete cover of at least 4" thickness extending at least 6" to either side. Unless you want a concrete path through your garden along the route of the conduit, that's not likely what you want.

Rigid and intermediate metal are tough enough that you won't likely damage them while digging with hand tools.

PVC needs to be 18" under unless concrete protected.

Table 300.5 of the NEC should clarify all that for you.


Central AC is Icing up, but not cooling my house My central air conditioner isn't cooling like it used to. I noticed that the refrigerant lines entering the evaporator coil in the plenum were icing up. What might the problem be?

Chemically clean the evaporator coil with coil cleaner, buy it at an appliance store.is filter ok.buy a cheapie for ac season they flow more air.


Interested in home will mold problem . Can mold be in carpeting? Howe do i remove Interested in purchasing a home that has been empty for several years. Has a little mold on upstairs walls able to take care of that. One room has ceiling repairs with mold. Can the  mold go up into installation and will I have to remove all and resinsulate ceiling. One room has paneling how can I check for mold? Will I also have to replace carpeting because of mold. How can you tell if carpeting had mold.

This is not a DIY job. Mold can spread everywhere in a wood-framed house full of drywall. Call in the pros to estimate the source and extent of the infection. Simply killing the mold won't help if you don't find the moisture source that made it moldy in the first place.

PSA to the world: stop building houses out of wood and drywall. Sheesh, what awful materials.


Can 2300 watt washing machine burn out wiring in my house? My standard voltage is 230 V and the socket is 16 A. I am asking the question because I had a 1500 watt water heating rod connected with another 15A socket which did burn out my home wires after a week of use.

Your socket and wiring (if properly installed/rated) are good for 3,680 Watts (230V X 16A.) As such a 2300W device should be perfectly fine.
However:
If a 1500W device "burned out the wires" on a 15A 230V (3,450W) socket, either the wiring in question was improper/defective, or there were other things also connected to those wires. In any case, somehting was wrong if the wires burned out rather than a circuit breaker (or fuse) tripping (or blowing.)
So your wiring installation may be improper or defective - it is at least suspect, and should be checked by a qualified electrician to identify and correct any dangerous deficiencies.


Oscillating or Drum Floor Sander I'm refinishing the floors in a 4 bedroom house, built circa 2003. The house is roughly 1800 sqft total. The 4 bedrooms have pine floors, while the living room and the hallway are some sort of hardwood. Considering the tile in the kitchen and bathrooms, I would estimate that the pine covers roughly 800 sqft, and the hardwood approximately 500 sqft.

I've watched videos, read articles, and actually helped refinish floors a decade or two ago, so I have a loose idea what I'm getting into. My one uncertainty is the type of sander I'll need.

The hardwood is generally in good shape, except the finish is badly worn, especially in the high traffic areas. The pine's finish is much better, although the level of the boards does not seem to be nearly as even. Still, it's not horrible in my opinion.

Do you think using an oscillating floor sander with a low grit would be a reasonable choice (for the hardwood, or both), or would I be killing myself? Would I be better off with a drum sander?

Secondly, can anyone help estimate what grit of paper to start with, and how much I would likely require? I'm just looking for a ballpark of 5, 10, 25 sheets.

Hardwood

Pine

Drum sander was the best solution. The pine boards being uneven was a big enough problem on it's own. Even with 40 grit paper on drum sander it took multiple slow passes on an angle just to get the floor flat enough to be able to sand the entire board. Oscillating sander would have taken forever.

As far as paper, 5 sheets of each grit should be plenty to refinish that amount of space. I may use closer to 10 with the lowest grit, because some of the pine floors are so uneven.


How to connect Al to Cu wire I just replace a 42 year old electric range.  The supply line was Al, and the pigtail from the old range was CU.  They were connected in a junction box with gray colored wire nuts.  The connection appeared to be in very good shape without any corrosion or oxidation as might be expected.  The replacement range had the same size copper stranded pigtail.  I connected the same way and it appears to be OK but seems I've heard bad stories about connecting to copper to Aluminium in this manner.  Will this be OK?

Aluminum wire is bad. It will prank call your friends, and steal your girlfriend.

No seriously, you just need to make sure you are terminating it properly and use splices specifically designed for aluminum wire connections.  These must have a rating of CO/ALR (COpper/ALuminum Revised).

Now to go deeper into the ooga-booga-scary aluminum wire.  Where it got into big trouble was trying to use it for the thin wires used in outlet and lighting circuits (14/12 AWG copper, 12/10 AWG aluminum).  This was originally done due to the scarcity of metals in post-WWII reconstruction.  They made hasty choices of aluminum alloy and termination design, and it didn't work and caused fires.  They solved it three ways:

improved the terminations (now CO-ALR).
improved the aluminum alloy (banned AA-1350 and now require AA-80xx)
Stopped using it for the thin stuff (12/10 AWG) since there isn't much cost savings.

I prefer copper up to 6 AWG/50A, and aluminum above that.

You might consider replacing your electric cable to your range, for a totally different reason: you probably have 3-wire (hot-neutral-hot), no ground. Any problem with the neutral wire will electrify the chassis of the range and kill you.  It happens.  Ground can be retrofitted separately, but why not seize the chance to dump the archaic AA-13xx cable.


Connecting Three 12 Gauge Wires When I purchased our house the previous owners recently installed electric baseboard heaters in rooms A, B and C.  I did not want to keep these but needed more outlets so I had swapped the breaker at the panel so I could run 110 volt instead of 220 volt.

Originally the feed line (from the panel) ran from the panel to the heater in room A. It was then spliced directly on the unit and a line ran to rooms B and C.  After removing the baseboard units I ran the feed line to the outlet in room A.  I ran a line from the outlet to a junction box, then spliced in the lines that go to rooms B and C.

Last night, one of the outlets that is connected at the junction box stopped working, then started working but received very little power.  I immediately cut the power to the line at the panel.  The other two outlets were working properly.  It was really late so I didn't dig into the problem too much but did verify that the connections at the outlet were tight. I am assuming the problem is somewhere in the junction box.

Since the lines were originally running 220 they used some 12/2 wire.  When I put in the junction box I had a hard time getting a good twist on the wires before putting on a wire nut and was worried that at some point they would come loose.  I am pretty sure I used the red wire nuts which I think should be the correct ones, right? I don't think wrapped them in electrical tape but should I?  Any tips on how I can keep this from happening again?

You have to use the right size wire nuts, and you have to put them on correctly. If you recall correctly, you have the right size, so you may not have put it on firmly enough. Another common problem is not having all the wires at the same length, so that one is not as well connected. Only when connecting stranded and solid should the stranded be just a bit longer/further into the nut than the solid wire(s).

You may find it easier to use a nut with "Wings" that make it easier to twist forcefully.

Do NOT pre-twist the wires. The wires, stripped to proper length (per instructions of the wire connector - look on the box) and aligned with each other are twisted BY the wirenut as it's installed (some instructions may say "pretwist optional" but in point of fact I find that it works best if the twisting is all done by the wirenut.)

Tape does nothing to prevent or solve a poor connection.


Name of metal tube for water shutoff access I had a leak in my yard and when I dug up the mud to figure out the problem, I found that somebody had buried the pipe/riser(?) for accessing the shutoff valve right on top of my water line.  I was further actually quite surprised to find the shutoff buried there in the first place because there was no indication that the shutoff valve even existed.

My question is what do you call the metal tube that you would open up and run the curb key down in order to shut off the water?  It reminds me of a round irrigation control box, but none of the things that I have googled have turned up what I found buried.  It has a pentagonal bolt on top to keep joe schmo from opening the tube and I would like to get a new one that is slightly shorter than the one I unburied because the buried one would stick about 3 inches out of my yard.

I recently had a similar problem fixed; the city called this a curb stop valve.

Alternate reference (using the terms "curb valve" and "sidewalk valve"): http://www.harriswatermainandsewers.com/news/article/water-line-curb-valve-sidewalk-valve-how-they-function


How do I patch this hardwood floor strip? I live in a >100 year old apartment building with a lot of temperature variation and the hardwood herringbone oak flooring is starting to show its age. What is the best way to patch this spot where two strips meet? Each strip is 2.5 inches wide and 18 inches long. The end of one strip was at some point cleanly cut in the past, and now the strip that is laid perpendicular to it has cracked. I would rather fill in the gap with a temporary solution than will get me by for a few years than do something more permanent like replacing both strips.

Here is the general area:

Closer view:

Side view:

Two more from the top:

By the way, that little white fleck is a grain of rice, not an insect.

I'd gently lift the cracked strip into its original position, then fill under and around it with a stainable, hardening wood putty. Once it's cured, stain it to match the lighter color in the wood grain. Use a permanent brown or black felt pen to simulate the dark grain.


Insert a 1/4 20 Threaded rod into a threaded 21/64 hole through metal I'm installing a suspended lighting track system in a concrete ceiling. The ceiling has some abnormalities and the anchors (seen here:
https://www.grainger.com/product/DEWALT-ENGINEERED-BY-POWERS-Vertical-Rod-Hanger-Anchor-54PD63) I've installed are slightly off so that when I insert a 5 foot 1/4 20 threaded rod, they all hang un-level (there are about 16 of them in total). I know that I can bend the rods to appear level - but I thought a better solution would be to purchase these from mcmaster carr:

https://www.mcmaster.com/#6154k13/=1e11k1b

This pivot adapter can screw directly into those ceiling anchors.

The problem now is that the set screw cavity (which the threaded rods will go into) is 0.328 or 21/64"

I can't find a M 0.328 to F 0.25 adapter.

Any ideas on how to do this? Should I just use a hand-tap to make that hole 3/8 so that I could more easily find a 3/8 to 1/4 adapter?
Is there some kind of sleeve I can insert to accept the 1/4" threaded rod.

Per the answers below, I just want to clarify that I am using the set screw threading to insert a 1/4" threaded rod. The hole is too big and I can't find an adapter suitable. Thanks!

****Ended up just ordering threaded rods @ 5/16 24 which fits perfectly in the coupling. The 15 degrees from center of movement is perfectly fine because the threaded rods are 5 feet long. Did a strength test too and the couplings are more than suitable to support the lighting track. Thanks everyone for your help in troubleshooting.

Let me take another swing at this.

This is a common issue when hanging pipe or conduit: your threaded rod goes up, but you need adjustability.  Preferably without having to take it all apart.

I would use a basic pipe strap.

Cut it so there are an odd number of (major) holes. Make a loop. Then use a short 1/4-20 screw to go through first a washer, then both outer holes (creating a loop around the screw head), then on into the concrete fastener.   Now a loop of pipe strap dangles from the fastener.  Run the threaded rod up through the center (bottom) hole, then a washer, then a nut. It will stretch out vertically, but you can turn the nut to adjust height.

First, that binder isn't made for .328 rod.  It is made for solid 1/4 to 5/16 rod, exactly like it says on the tin.

Now, using the setscrew hole is not a great plan.  It's the wrong size and pitch (finethread), and you won't find an adapter from 1/4-20NC to 5/16-24NF (if it's even that), not even a helicoil.

Also, the fastener only pivots 15 degrees from straight, but even if that is acceptable, it's not made to have tension loads through the ball joint, it's designed for shear loads across the ball joint.

However I would also consider standoffs like these if you can find them in 1/4-20.


Electrical outlet in low voltage bracket? I generally do my own electrical work but needed to upgrade my service from 100A to 200A so I hired someone. I had them add some outlets to my garage while they were at it because I was feeling lazy.

Today I decided to add more outlets and noticed they used low voltage brackets rather than the enclosed junction boxes I always use. I am assuming this is a code violation, but before I complain I wanted to ask here. I live in California if that matters.

What sort of joker did that?

Clearly, whichever joker did that needs to be sent back to their apprentice electrician's training, because line voltage connections need to be in a box!  If you see them around again, be sure to thwap them upside the head with NEC 300.15 for me, OK?  (P.S. none of the exceptions in 300.15(A) through (L) apply to this situation.)

  300.15 Boxes, Conduit Bodies, or Fittings - Where Required. A box shall be installed at each outlet and switch
  point for concealed knob-and-tube wiring.

  Fittings and connectors shall be used only with the specific wiring methods for which they are designed and listed.

  Where the wiring method is conduit, tubing, Type AC
  cable, Type MC cable, Type MI cable, nonmetallic-sheathed
  cable, or other cables, a box or conduit body shall be installed
  at each conductor splice point, outlet point, switch point, junction point, termination point, or pull point, unless otherwise
  permitted in 300.15(A) through (L).


is there a sandable compound I can use for a final skim coat over StructoLite plaster? I had to rip out a 4' x 6' section of ceiling and wall to make a plumbing repair on our house. The original walls were 1940s era gypsum board reinforced at changes-of-plane with metal lath.

Some sagging of the joists had caused a slight bow in the ceiling, so I couldn't repair the ceiling with a piece of drywall, because the board see-sawed.  So I nailed metal lath to the joists and applied StructoLite like old-school plaster in three coats: a thick scratch coat, a brown coat, and a final veneer coat.

The wall turned out really nice with a creamy smooth finish but my overhead troweling skills aren't so good, and the ceiling has a lot of trowel marks.

So I want to trowel on a sandable skim coat compound which will adhere well to the StructoLite. What would be a good choice?

Any tips would be appreciated too.  Do I want to mist the plaster beforehand or wipe it down with a damp sponge?  It has been curing for about two weeks.

You can use a setting type of drywall compound like Durabond. You will need to apply at least two light coats to finish.


How to prevent half wall (drywall, steel studs) from wobbling I want to make a half wall beside a staircase (on the edge of the upper floor). One end will be attached to a concrete column, but the other will be (so far) unsuported. Something like the picture below:

What is the best way to ensure that It stays put and strong? If nothing else I will make a square tubing post (100x100mm, 1.5mm thick) from floor to ceiling and attach the drywall to it.

Any other ideas?

EDIT: No wood studs in Brazil, actually it is very hard to get good construction lumber around (most aren't dry, and pressure treated is rare and expensive as hell).

Residential steel studs aren't rigid on their own. They get rigidity from the surfaces they are connected to along with the drywall that is attached.

For a wall like that, I'd want to treat it like a newel post on the end and have it be a 4x4 blocked and bolted to the joist below it for rigidity.

Otherwise, your idea to just make it a full column would work too.


What type of compression fitting do I need? I purchased a GE PLV1817XSS dishwasher and I am trying to connect the water to to the dishwasher intake, but I'm having trouble finding the correct fitting. The water intake is an unthreaded plastic tube that sticks out the back. The instructions(Spanish) are extremely vague and simply say to get a 90 degree elbow, but give no indication of what size of anything is needed:

I had purchased a Braided stainless steel water hose which comes with an elbow (3/8" FCM (Female Compression) x 3/8" MCM (Male Compression) 90° brass elbow), thinking that this was all I needed, but I didn't realize that it lacks the compression nut that goes with it.

The outer diameter of the water inlet tube is 14 mm (measured with a vernier caliper), but when I went to a place that specializes in brass, they said they don't have anything that measures 14 mm, since apparently that isn't a standard size. They had one fitting that is 12.8 mm, which is too small, and another that is about 16 mm, which (I think) is too big. Can anybody give me an idea what I need to get the water connected to this thing? Do I need something else besides a brass fitting that might come in different measurements?

I called the support number listed in the manual and they told me that they wouldn't help me unless I paid for a certified technician to do the installation. Thanks, GE.

Edit: Apparently that tube sticking out the back is not the water intake. The water intake is on the front of the dishwasher.

You don't need the compression nut. With that water hose, you should connect it directly to your water supply shutoff valve.

The compression nut is used when you have a copper pipe as your water supply, like this:

If that's what you have, remove the nut and the copper pipe. Your braided pipe connects to the water supply like this:

And connects to your dishwasher like this:

Use the teflon tape ONLY on the threads between the elbow and the dishwasher. The braided hose has a gasket so DO NOT use teflon tape on those threads.


Do I have a natural spring or a leak I live in South Mississippi and have lived in my home with a slab foundation for about 20 years.  I have never had a problem with the foundation and the ground is mostly red clay.  We do have a septic system which was replaced about 2 years ago with an aerobic system that drains into the woods about 50 yards away.  About a month ago I noticed water standing next to the foundation (slab foundation).  I dug around it and it filled up with water.  There is a faucet right there that has leaked at the faucet but I can turn it off enough not to leak.  I've monitored the water meter and there is no leak coming into the house.  I dug a small trench to get the water to run away from the foundation. The water does not smell and looks clean, not cloudy or grayish.  The man with the water company in our community said it is probably a spring and will dry up on its own.  When they installed the new septic system they hit at least 2 other springs in the yard within about 30 feet of this area.  I'm just concerned that maybe the water from the bathroom sink or tub is causing this leak.  They are both right where this water is showing up.  I even took green food dye and put it in water from the sink, bathtub and toilet but nothing showed up outside.  I let the water run yesterday for a while with no change in the water level.  But when I looked this morning the water was up.  Of course I had been digging in the area so that may be why the water has increased.  The water level never gets very high and stays about the same except for this morning.

How does the clean water supplied by your utility company differ from natural spring water? Where I live, tap water contains chlorine and chelating agents, and natural spring water contains none of these. Your water company will be able to tell you how to chemically test for tap water vs. spring water.