28 votes
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Turn off hot water without hot water valve

My approach would be to turn off the water heater and the cold supply. Then open a hot tap below, or as close to the area of the leak, to drain the hot pipe. Then be prepared to catch the remaining ...
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27 votes
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How do electric hot water heaters explode and what can be done to prevent that from happening?

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. ...
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  • 55.1k
24 votes

How do electric hot water heaters explode and what can be done to prevent that from happening?

Consider the sources; it is plumbers giving you a scare story to get you to hire them. See also "aluminum wiring". It will take a chain of 3 events at once: failure of the thermostat, causing ...
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12 votes
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What is this plumbing "temperature regulator" called, and how do I adjust it?

Thermostatic Mixing Valve According to the installation instructions (PDF) Let the water flow for at least two minutes to allow supply temperature to stabilize. Calibrate the mixed water outlet ...
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  • 128k
11 votes

Should I be calling a plumber or someone from my water supply company to test for contaminents in my water?

If you are on a public water supply, there may be water test results already published on a quarterly basis. If you are doing your own testing, generally an environmental testing company or ...
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  • 136k
11 votes

What type of hose should be used when flushing a water heater?

If you're going to flush the hot water heater you might as well turn it off and then take a shower or do a load of laundry. That way the water will only be lukewarm when you flush the tank and you won'...
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  • 13.7k
10 votes

Should I replace all the copper pipe in my heating system with PEX?

How often does your heating system spring a leak? It's not particularly often in my (long) experience with closed-crcuit hot water heating systems - less than once per 20 years, I'd say, and usually ...
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  • 136k
10 votes
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Are electrical screws a standard diameter?

There's no reason it would not be a locally standard size (given a British location based on the label, presumably metric or pre-metric British Standard threading) so some basic measurements (no ...
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  • 136k
9 votes
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Why does my water heater's drain line rejoin the outlet pipe?

What you describe sounds like a Gravity Fed Hot water re-circulation system. It's designed to keep hot water available at the kitchen sink without having to flush cold water out of the pipe first. ...
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  • 4,140
9 votes

How do I get 150F water to the dishwasher?

You don't. Let the dishwasher do it for you. I have read in a maintenance manual that the ideal temperature for incoming water to a dishwasher is 150F. Was it a maintenance manual for your actual ...
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9 votes

Hot water tank loses heat by closed loop gravitational circulation - need to improve thermosiphon

OK, so you have a 3-loop system. The inner loop is freon, for the heat pump. The intermediate loop is service water (or antifreeze) which you heat/store in a 300l (80 gal) tank. Then you use the ...
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8 votes

How do electric hot water heaters explode and what can be done to prevent that from happening?

An electric water heater explodes when the water in it starts boiling, producing pressurized steam that causes the heater to rupture. In order for this to happen, three things all need to fail; if ...
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  • 577
7 votes
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What type of hose should be used when flushing a water heater?

While there are "hot water hoses" and you'll pay a pretty penny for them if you want more than the standard 5 feet or so that washing machine hoses are, you can use an ordinary garden hose. Why? No ...
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  • 136k
7 votes
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Is wrapping Roxul around hot water tank pipe a fire hazard?

No. As you seem to be aware, Roxul is a mineral wool product, and mineral wool is fireproof. You're right that it will "trap the heat" but this is exactly what you want and the result will be less ...
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  • 12.2k
7 votes
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PEX pipe burst: what else needs to be fixed to prevent it happening again?

PEX pipe does not corrode or otherwise interact with copper or other materials the way dissimilar metals do. It's essentially an inert substance under normal circumstances. The bulges and darkened ...
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  • 20.5k
7 votes
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Replacing toilet shut-off valve and need to turn off water; Need to turn gas water heater to pilot?

Do I need to set the water heater to pilot, in order to avoid the dangerous scenario outlined above? Doing anything to our water heater makes me a bit nervous. NO, In the amount of time that it will ...
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  • 13.3k
7 votes
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Why does the water from my shower get hotter when I use a shut-off valve?

Let's flesh this into an answer. This happens with my kitchen faucet and one of those "quick-flip - not quite total shutoff" valves that screw into the aerator. My guess is that some hot ...
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  • 136k
6 votes
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Code for elevating water heater in garages?

As I suspected, the code you're referencing is from the National Fuel Gas Code. I was not able to find anything in National Electrical Code, or International Residential Code that mentions this in the ...
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  • 128k
6 votes

Should I be calling a plumber or someone from my water supply company to test for contaminents in my water?

As @tyler durden comments, this may be an issue with the drain, but it is very unlikely that there is no trap. A more likely scenario is that a partial blockage or obstruction of either the drain line ...
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  • 33.5k
6 votes

How do electric hot water heaters explode and what can be done to prevent that from happening?

Well, the answer is right there in the article you linked: Always check your hot water heater’s pressure relief valve to ensure it is in good working condition. If you have any concerns that ...
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  • 4,827
6 votes

Why is this apartment water heater so much more expensive than my bigger home one?

I think it's fear of downgrading. I think the pro plumbers are unwilling to downgrade them. For instance, the latest Codes require water heaters to have better insulation than they did before. This ...
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6 votes

Unable to turn knob on Rheem hot water heater to pilot

Below is a picture of the lighting instructions for your water heater taken from Rheem's website. Make sure to follow the lighting instructions carefully and do not skip any steps. This same ...
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  • 10.8k
6 votes

Can I switch the hot and cold water supply to improve the pressure of hot?

Your question boils down to "please validate my wonky idea" and I will absolutely NOT. Yes, you can do it but you shouldn't. At best your proposal is something that would be done in a super ...
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  • 10.8k
6 votes

Hot water tank loses heat by closed loop gravitational circulation - need to improve thermosiphon

As mentioned by others, the tubes should be insulated to reduce the thermoflow and losses in general. If the thermosiphon is not directly installed close to the tank's in- and outlet, the uninsulated ...
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  • 2,358
6 votes

Can I wire a switch to toggle between the top and bottom outlets of a 1 gang receptacle

Crazy but in a good way. Brilliant actually. Use any common 3-way switch, I don't see a problem with it. The only issue that might call for a 2-gang switch box is the need for GFCI protection on both ...
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5 votes

Desuperheater vs Heat Pump Water Heater

I've been looking into a heat pump replacement. You said "However, when the heat pump is in heating mode, the exiting refrigerant line is actually colder, not hotter, than when it enters. As a result, ...
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  • 51
5 votes

Dropped Item in hot water heater

Since you have a flue I assume it is either gas/propane or oil fired. Most water heaters have cover near the base to service the burner or the igniter. First shut off the fuel source. If you remove ...
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  • 10.9k
5 votes
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Need help understanding gas water heater

A - Expansion tank. This prevents the pressure increase due to heating water, from damaging the plumbing. The tank is filled with air, that is separated from the water by a bladder. When the water ...
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  • 128k
5 votes

Are water heater elements like light bulbs in that they either work or do not work?

The symptoms you describe are consistent with a failed lower element. An electric water heater typically has two elements (and two thermostats). Only one element operates at a time. Under normal ...
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5 votes
Accepted

Can one get instant hot water from home faucets without a heater?

No method is "instant" but there are long-used and accepted methods of recirculating your hot water piping system back to your water-heating appliance, which keeps the line at least warm (or ...
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