For questions generally relating to the hot-water supply system of a typical residential or commercial building, primarily regarding the heating mechanism itself (a traditional hot water heater tank, tankless heaters including "point-of-use", boilers and heat exchangers, etc).

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Are galvanised steel pipes suitable for supplying hot water?

I am living in an old building where the old galvanized steel pipes are still in use indoors. Rather than upgrading to copper pipes, can I reuse these galvanized steel pipes for hot water (from a ...
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1answer
588 views

Local “point of use” hot water heater

This question is a follow-up to It takes a minute or more for the water to become hot from any of the faucets in my house -- how can I speed this up?. I have a tankless water heater, and it takes ...
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1answer
74 views

Does a larger solar water heater equate to better water pressure?

Please excuse my ignorance - we want to buy a typical slanted rooftop solar water heater for our home. We thought 200L would be an acceptable capacity, but the vendor we visited today said that we ...
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5answers
434 views

Is it okay to flush water heater onto the drip pan with drain hole?

Our water heater is on the second floor and we need to have it flushed. It has a drip pan with a hole that has a tube attached to it. Common sense tells me that I can flush the water heater directly ...
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3answers
765 views

Is there a way to get hot water without altering plumbing or electrical wiring too much?

Is there a way (other than collecting water and heating it on the stove ) to get hot/warm water from the tap without having to alter existing plumbing or electrical wiring ?
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3answers
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What advantages does bending copper pipes have over joining many parts without brazing?

These questions are in context of a DIY solar water heater I am planning (another separate question). The copper pipes in question, are supposed to carry around hot water using thermo-siphon ...
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1answer
437 views

How to determine tankless water heater requirements?

I'm considering replacing my insufficient 30 gallon gas water heater with a tankless water heater equivalent to 50 gallon gas heater. I know a 50 gallon heater would serve my needs. Questions ...
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1answer
509 views

Can I reuse cold water copper pipes for hot water?

I have a segment of copper pipe for supplying cold water to my gas heater currently. It runs inside a wall so I don't want to replace it. Now I need to change the piping and want to reuse that ...
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3answers
14k views

How do you know when you need a new water heater?

Our hot water is hot sometimes, but not always. For example I might be able to fill up a tub with hot water one morning, but the next morning the water might be cold. This is our first home and when ...
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1answer
431 views

Should I run two gas water heaters if I don't need to?

We purchased a house recently that has two water heaters(configured in series). I just realized that the first one hasn't been running as the thermocouple was defective. For 6 months we had no problem ...
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2answers
540 views

How can I identify the source of a leak at the hot water heater?

My water heater has a slow leak. From what I can tell so far it is coming from either the cold water inlet or the hot water connection. The cold water inlet seems to be the culprit to me because that ...
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1answer
2k views

Water heater builds up excessive pressure only when reheating the tank. What's going on?

The pressure release valve on my water heater will trip predictably after a significant amount of hot water has been used (e.g. dishwasher, laundry, long shower) releasing 16 oz or less of water. It ...
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2answers
14k views

troubleshooting a hot tub/spa that won't heat up

We have a Hotsprings/Watkins brand hottub/spa that came with the house we bought last September. At the time that we bought it, the hot tub appeared to work and heat up properly. However, now that ...
3
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1answer
110 views

How long should the hot water last during a shower?

Given a 40 gallon natural gas water heater, and a shower head with a flow rate of 2.5 gallons per minute. How long should the shower be able to maintain 105°F water temperature? Assume the average ...
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2answers
67 views

How can I go back to a gas water heater?

I recently got a condo unit (low rise condo) on the 4th (top) floor. The unit previously had a gas water heater but was replaced with an electric unit after the gas one broke down I suppose. This was ...
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2answers
677 views

What does the low pressure light on my Rinnai tankless water heater mean?

We have a Rinnai tankless water heater in the basement. Our housemate has a bathroom in the basement. About once a week, the water turns cold during her showers or when she uses the sink. We have no ...
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1answer
895 views

How can I prevent water from entering through water heater/furnace exhaust vent?

I have an exhaust vent in my basement (Amerivent Type B) which takes the exhaust from my gas furnace and water heater goes out the basement wall, and up my chimney. A little bit water is coming in to ...
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2answers
1k views

How do I improve hot water pressure from a gas combination boiler?

I have a gas combination boiler (no hot water tank). The hot water pressure isn't very good though - the showers and hot taps come out with maybe half the pressure when compared to the cold straight ...
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1answer
974 views

Why does my gas water heater's pilot light go out when I replace the outer door?

I have a 9 year old Bradford White gas water heater, model MI403S6FBN4. The pilot light went out today, and when I went to re-light it, it stays lit while the pilot button is held down, and it stays ...
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2answers
933 views

Is it okay to put a heat pump water heater in a crawl space?

I have a pretty large crawl space. It is 80 inches wide and around 7 feet high. I am looking to replace the 50 gallon electric water heater with the new Geo Spring Water heater by GE This unit is wide ...
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1answer
314 views

Why does my Rinnai Infinity water heater fire up after turning off the cold tap?

I have a Rinnai Infinity XR20. It's about 3 years old. I've just recently noticed a peculiar issue with it that I hadn't noticed before. If I turn on a cold tap like the one to the garden hose and ...
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1answer
456 views

How well would a hydronic furnace work with a gas tankless water heater?

My current heating system (in Ontario) is an oil hot water tank in a closed loop with a hydronic forced-air furnace (Enerzone XAH 68). The water circulates through what is basically a heat exchanger ...
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1answer
1k views

Is it OK to have a gas water heater in a bedroom closet?

I have a laundry room with a gas water heater in the closet. I was thinking about taking out the washer and dryer and renting the laundry room as a bedroom because there is a bathroom next to the ...
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1answer
270 views

Is it safe to simply replace a heating element in an electric water heater?

The bottom element in my water heater burned up. I took the bottom panel off, and everything inside was scorched - the insulation, the plastic cover, the thermostat - even the edges of the panel. The ...
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1answer
2k views

What could be causing water to drip from the relief valve of my new gas water heater?

My old hot water tank met its maker about two or three weeks ago, and since then I have installed a new Kenmore 50 gallon gas water heater to replace it. The new water heater seems to work fine, I ...
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2answers
7k views

After installing expansion tank, massive buildup of pressure then a trickle?

I am completely stumped. You guys helped me out a lot with my previous question here: New gas water heater dripping relief valve, have expansion tank, what gives? Turns out the expansion tank ...
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1answer
331 views

What could cause the hot water not to work after replacing a water heater?

I replaced my hot water heater and now the hot water doesn't run in any of my faucets. What could be the problem? I did not have to replace any piping from old hot water heater and the water ran fine ...
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3answers
4k views

How does a water-heater know when to turn on?

Now that it is getting colder, we have noticed that when we get home from work, our water is not that hot. It was warm at best after a four-day trip. The water heater is in an unheated basement, ...
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1answer
492 views

A boiler and a hot water tank … what is this configuration? (UK)

I'm a west-coast American living in London. I've mostly known homes with electric baseboard and central forced air heating, and a single hot water tank for showers and taps. In the UK hot water fed ...
2
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1answer
170 views

Two Water Heaters - One off affecting the other?

We recently moved into a property with 2 water heaters installed. These were installed less than 3 years ago, so they are relatively new. Now, in an effort to conserve electricity (we are just 3 ...
2
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1answer
2k views

Why won't my gas water heater light?

Everything was working last night but no hot water this morning. Things I have checked: gas supply to the house is fine electricity is going to the boiler fuses are good sounds like the water pump ...
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1answer
1k views

Is corrosion on top to an otherwise working electric water heater dangerous?

I moved into a house with an electric hot water heater. The heater is old (11 years) but works just fine. However, the top of the tank has extensive corrosion, especially around the connections for ...
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1answer
304 views

Can I use a small propane instant hot water heater for a clothes washer?

I would like to set up a clothes washer in a location that has only cold water. (It will be in a makeshift shed of some kind, with a hose and an extension cord.) I could just wash everything in cold ...
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2answers
902 views

Hot water stops flowing after clunking noise

When I turn the hot water on in the bathroom faucet, a clunking noise sounds, and the water stops flowing. If I open the faucet quickly, it happens immediately. If I open the faucet slowly, it takes ...
2
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1answer
639 views

Why does my Paloma tankless water heater turn off randomly without errors?

We have a Paloma Tankless water heater, model: PTG-74PVN that shuts down when in use for a few minutes. There is no code displayed on the screen, it just powers down. This started happening a few ...
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1answer
50 views

Is there a danger of back flow from water heater while replacing a saddle valve?

We have a leaky saddle valve feeding our humidifier. We eventually want to get a real valve installed, but for now are looking for a cheap near-term solution. Here is my concern: the original ...
2
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3answers
412 views

Does a thermocouple need to be screwed in to work?

I'm recently having trouble with a water heater. The pilot light with ignite just fine, but will go out after releasing the reset button, even after holding it for over a minute. That makes me think ...
2
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1answer
219 views

Plumber told me it's unsafe to drain my water heater — what should I do?

We are new homeowners. Our 11-year-old 2nd-floor water heater was leaking and the first plumber who came told us he would need to come back with a partner to take it away. I asked if I could drain ...
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1answer
98 views

How do I start a cold gas heater?

The gas heater pilot light has been out for a couple of days, and I believe there is a safety mechanism that detects this, and shuts off the gas. Now, when I move the slider to the pilot light ...
2
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3answers
7k views

What is causing my gas water heater to squeal?

I have a gas water heater. Starting yesterday, when the flame is on, the unit makes a squealing noise of moderate volume. The noise stops immediately when the flame turns off. This means it is not ...
2
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1answer
26 views

When do tankless hot water heaters need to be descaled?

I had a Bosch tankless natural gas hot water heater that stopped working with C7 and EA error codes and the plumber indicated that the unit had failed due to water getting into the internals like the ...
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2answers
44 views

What should I use to cover the walls of an alcove for a water heater?

My water heater is located in an alcove on the back corner of the house. Today I found water line leaking from the heater, replaced and it is good now. I have always just assumed the walls and ...
2
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1answer
39 views

Should I replace an old breaker or add a new one?

Our old circuit breaker for our water heater seems to be at the end of its life. However, the breaker also controls our well system, and the breaker is only 20 amps. Is it okay for us to just replace ...
2
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2answers
317 views

How to calculate potential energy savings from using a tempering tank?

I have a boiler (oil) with integrated water heater (3.5 gallon). I don't have problems with running out of hot water but I do wonder if having a tempering tank before the boiler would save money on ...
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2answers
542 views

How can I prevent the intake vent for an on demand water heater from getting plugged?

We have a Navien on demand cold water heater. The intake and outlet vent pipes run out through the poured concrete foundation and have a plastic grill on the end. If the intake vent is blocked in any ...
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1answer
592 views

Can replacing a T&P valve be done as DIY by a home owner?

I want to replace the T&P valve on my gas water heater since it is dripping water all the time. I talked to a couple of people such as my friend and a salesperson at a Home Improvement Store. They ...
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1answer
4k views

Why is my electric hot water heater producing lukewarm/cold water?

Yesterday after returning home from work I discovered my hot water is not working. When you turn on the faucet (any in the house) just a little warm water comes out and then it turns cold. I checked ...
2
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1answer
285 views

What's with the different FHR ratings of these hot water tanks?

We're replacing our tank with a more efficient one and we can't go tankless given the cold input temperatures in Canada and the amount of output we need (for a triplex with 7 people). So I've been ...
2
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1answer
232 views

Why does my water heater stop after a few minutes?

I have a Junkers (European water heater) that works for a few minutes and then stops. Anyone have experience with this/know how I can troubleshoot? Or, would a regular plumber be able to fix it?
2
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1answer
184 views

What to look for in a new water radiator?

The water radiators I have under each window are 50 years old, and I would like some new ones. They measure HxLxD 50x100x20 cm. The new ones I would like should be as thin as possible. I live in an ...