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).

learn more… | top users | synonyms

3
votes
1answer
465 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 ...
4
votes
3answers
497 views

Calculate savings from/cost-effectiveness of installing a tankless hot water heater?

Following up on "Which water heater types do you recommend?" and "Are tankless water heaters worth it in cold climates", is there a way to calculate the point at which installing a tankless water ...
2
votes
2answers
6k 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 ...
2
votes
1answer
303 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 ...
4
votes
1answer
3k views

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 ...
1
vote
2answers
445 views

Sizing DHW expansion tank for tankless heater

I have a combined boiler for hydronic heating and DHW. Earlier in the winter, I started insulating as much of the pipes I can easily access. This has led to hot water coming out of the cold water ...
0
votes
0answers
265 views

Running Shower Faucet After Hot Water Heater's Off

I was awoke by a chemical smell from my electric hot water heater. The past two weeks I noticed my shower was not getting/staying very hot during my 10 minute showers. Thinking not too much about it, ...
2
votes
1answer
601 views

No hot water, but exhaust blower running continuously

This morning I went to take a shower and there was no hot water. I went to the basement to check on the water heater, and found the exhaust blower is running continuously but no hot water is being ...
2
votes
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 ...
5
votes
3answers
2k views

Are hot water returns worth putting in?

Once I saw on an episode of This Old House that they were putting in hot water return lines: pipes that recirculate idle hot water back to the heater so you get hot water right away, instead of ...
4
votes
1answer
3k views

Why won't my water heater stop filling?

I noticed tonight that my water heater appears to be trying to fill with cold water, but it won't stop. I can hear water flowing through the pipe, and the overflow drain pipe (white one just above the ...
0
votes
1answer
909 views

Why did my hot water stop?

I have a Rinnai RL94 tankless water heater. Today something went wrong and now I have no more hot water. The machine is not showing any kind of error code like it has in the past when things went ...
3
votes
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 ...
3
votes
2answers
519 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 ...
3
votes
1answer
425 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 ...
5
votes
4answers
1k views

Why do I have two parallel gas pipes?

I've got a water heater and a hot water radiator furnace sitting next to each other, both on gas. The strange thing is that there are two parallel gas lines feeding each one of these which come from ...
2
votes
2answers
797 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 ...
9
votes
2answers
401 views

What type/thickness of drywall should be used in water heater closet?

I have a rental house built in the 70's that had severe water damage in the small room (4x5 feet) that houses the hot water heater. The room is off of the garage. I've had the water heater replaced ...
10
votes
2answers
2k views

What caused a burn mark near my hot water pipes?

I was doing some household cleanup in the storage room where my heat tank is located when I noticed a burn mark on the wall frame near the pipe that goes from the heat tank to the shower next room. ...
2
votes
1answer
858 views

What is causing the high limit switch to pop on my electric water heater?

The high limit switch has popped twice on my electric water heater, both times at night. I reset the switch and the water heats and it's ok throughout the day. Wake up in the morning and it's ...
1
vote
1answer
373 views

How do I diagnose a hot water recirculation problem?

We have 2 ganged gas water heaters in a 10-year-old house. Professionals installed them last year to replace the 10-year-old pair. I'm pretty sure they are hooked up to a recirculating pump. This ...
1
vote
1answer
467 views

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

I'm a west-coast American living in London. I grew up with baseboard and central forced air heating. I'm currently living in the UK where water radiators are common (if not pretty much the ...
2
votes
1answer
166 views

How do I lower the temperature of an electric boiler in France/Europe?

My electric boiler is delivering VERY hot water: my hands are often burned when I forget to mix it with normal-tempered water. Do you think there is a way I can make the boiler heating the water ...
3
votes
1answer
399 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 ...
2
votes
1answer
3k views

My hot water stopped working in one bathroom, what can I try in order to fix it?

I have an electric water heater from 2004. The hot water works in all other areas of my house (kitchen, other bathroom and washing machine). The sinks and shower in my master bathroom are not ...
6
votes
3answers
56k views

Why is my hot water running out quickly regardless of other household water usage?

I've noticed that my shower, which used to run hot water for what seemed like forever, now can only produce about 15 minutes of hot water. This doesn't appear to be related to other water usage in the ...
4
votes
2answers
2k views

Do I need to replace my hot water tank's pressure release valve?

Recently we had an extended water outage. When water came back, pressure in the lines was much higher. The hot water heater started leaking from the pressure release valve and after flipping it a ...
3
votes
1answer
984 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 ...
11
votes
3answers
2k views

Are tankless water heaters worth it in cold climates?

I was thinking of switching over to a tankless water heater, but a friend of mine said they are not good in colder climates since the water coming in is colder and takes longer to heat. Is this a ...
2
votes
1answer
292 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 ...
4
votes
1answer
561 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 ...
1
vote
1answer
595 views

How can I monitor the temperature in a hot water heater?

When my hot, water heater runs out of hot water, I have to wait a while until it's hot again. I'd like a way to check the temperature without running water to the faucet every 10 minutes. Is it ...
4
votes
1answer
144 views

Is it possible - setting thermostat based on a seperate thermometer

I'm looking into building a solar water heater, but I'm wondering, is it possible (and what products should I be looking for) to turn on a pump when the water in the solar heating device is hotter ...
2
votes
1answer
860 views

Loud vibrating when using hot water!

I recently moved into a new condo with 2 kitchen sinks -- a main one and one embedded in an island. There's a lot going on under the main one -- the cold water is split so that it leads to the faucet ...
0
votes
1answer
223 views

How to calibrate continuous water Gas Heater?

i have installed a gas continuous water gas heater, it is around 30 mts of pipe away. my shower has a mixer valve (one unique lever for both the hot and cold water). The problem is, whenever I am ...
1
vote
2answers
177 views

I want a cheap solution for water heating, maybe even something I can build myself, please give me some ideas

I have a little problem, over summer we choose to run a wetback for our hot water, on some days over summer this is unbearable, please provide some helpful suggestions, things like solar ovens, solar ...
1
vote
1answer
477 views

What is the life expectancy / MTBF of a 60 gal. water heater?

Specs: Capacity: 60 gal. Power: 4500W Voltage: 240V Warranty: 6 years
3
votes
1answer
257 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 ...
4
votes
3answers
2k views

Rust spots on water heater — time to replace?

So I noticed today there's some rust spots showing up on the outside/bottom on the water heater. No more than a couple specs. Should I be worried?
6
votes
3answers
2k views

How do I troubleshoot a water-heater?

Lately our hot water has been running out very quickly, a lot quicker than it used to. I have an Whirlpool electric water heater with 2 elements with the top element has a reset switch. I followed ...
6
votes
2answers
3k views

What are the symptoms when 1 of the electric water heater elements goes kaput?

I suspect that something has gone awry with the electric water heater. We do get water that is plenty hot, but it doesn't seem to last as long as it used to. My suspicions are further aroused because ...
4
votes
2answers
2k views

Should my water heater drip constantly?

My wife was home today during a follow-up visit from the sump pump replacement we had as a result of my sump pump issue. After solving the problem, the plumber opened a the release valve from the ...
3
votes
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 ...
1
vote
2answers
699 views

Can I vent a dryer from the same mechanical closet as a water heater.?

I'm currently looking at a condo to purchase and the existing "closet" that contains the plumbing and venting for a washer/dryer is a bit on the small side. It's probably not that big of a renovation ...
8
votes
3answers
776 views

Are water heater blankets a good idea?

Is it a good idea to wrap a water heater in insulation? Does it lower the heating cost? Does it shorten the life of the water heater?
17
votes
1answer
383 views

Is flushing a waterheater a good idea?

I've been told that water-heaters build up sediment at the bottom over time, and should be flushed out (ie. drained, then allowed to refill). Is there value in this exercise? Does that value exceed ...