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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2answers
30 views

Will having an expansion tank on the hot water pipe cause any problems?

I want to replace my water expansion tank and I just found out that it is installed in the hot water pipe coming out from the water heater. From what I've read, it should be installed in the cold ...
1
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0answers
25 views

Recirculation pump seems to be working, yet no detectable heat on return pipe

Our two-story-on-a-slab house has uninsulated copper pipes, including a recirculation return pipe to a tee on the water heater drain. In past years, the recirculation seemed to give us hot water ...
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0answers
21 views

Vaillant ecotec 28 boiler pressure problem

I have a Vaillant ecotec pro 28 boiler and the pressure is too high when the heating or hot water is on. It flashes at between 3.2 and 4 bar. After searching online the suggestions were to vent any ...
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1answer
20 views

Frozen water lines, what should I do with my electric hot water heater?

I woke up yesterday (Thursday) morning to frozen water lines. Left taps open all day and still nothing. I will not be able to get anyone in before Monday or Tuesday to thaw the lines. I don't know ...
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0answers
61 views

Why does it take so long for my water to run hot and why does it not last in the shower?

I have a State electric compact water heater model 6-120. When I run the faucet it seems to take a long time for the water to run hot. About a minute or two. When I take a shower I can run the hot ...
6
votes
5answers
721 views

Prewarming for tankless waterheater

I have a tankless water heater that is just a little bit to small for our new house - the temperature rise isn't quite enough for the winter months. Our basement is big and relatively warm so I struck ...
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1answer
112 views

Why does my shower run out of hot water quickly?

My shower runs out of hot water quickly. Initially the water is perfectly hot, then it starts cooling after a minute or so and we need to adjust the lever to maintain the temperature. Somewhere around ...
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2answers
42 views

How can I adjust the temperature of my hot water?

I live in California and the winter has been a lot warmer than expected. I would like to decrease the water temperature in my home to try to save money and conserve energy. How do I do this?
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0answers
35 views

Annual KWh usage of electric ignition on gas water heater

I'm shopping for a new gas water heater and looking at possibly purchasing a more efficient version with electric ignition. However, I'm curious as to whether some of the savings will be offset by ...
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1answer
54 views

What to do when the cold water valve on the water heater is welded on?

Our hot water seems to be running out faster than usual, and thanks to this site, we were guessing that we probably have a broken dip tube in our gas water heater. Unfortunately, someone in the past ...
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0answers
40 views

Direct Vent Water Heater Flue Exhaust

We recently moved into a property with 2 water heaters installed in the basement. During the inspection, we were told that the water heaters were relatively new, but the exhausts were "odd". ...
3
votes
1answer
131 views

Is there a specific NEC code specifying the distance between water heaters and electrical panels?

I have a condo in a large building with many identical units. Several times other owners have mentioned that the original layout of the utility room isn't up to code due to the proximity of the water ...
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1answer
99 views

Low dynamic hot water pressure throughout the house

I recently bought my first home, and the first thing we noticed is that the dynamic hot water pressure is pretty low compared to the cold water pressure. I purchased a water pressure gauge and found ...
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0answers
63 views

How to prevent sudden changes in water temperature (shower)?

I have an apartment in an older building. The boiler apparently was recently replaced by the building manager in the past few years, but every time I take a shower, the temperature changes are pretty ...
2
votes
2answers
141 views

Code for elevating water heater in garages?

A gas/propane water heater in a garage is elevated. This is to ensure the open flame (at the bottom) is above a certain height (?) to avoid any combustible fuels in the garage from igniting. This all ...
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vote
1answer
69 views

Can I connect my water heater pan drain to the building waste drain? (CPC)

This question is relative to the California Plumbing Code (CPC), specifically the Sacramento area. I'm doing some remodeling of a bathroom where the water heater pan drain line comes across the ...
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vote
2answers
144 views

Legal water heater replacement

I'm looking to replace my water heater. I currently have a 15 year old 40 gallon gas water heater, and it's time to go. I had several quotes from local plumbers, and choked at the prices. I'm going to ...
3
votes
1answer
106 views

What disadvantages do thermostatic mixing valves have?

I will soon be buying a new water heater for my home. I want to set the heater to keep the stored water at least 140 degrees Fahrenheit (60 degrees Celsius), and use a thermostatic mixing valve to ...
1
vote
1answer
49 views

Merging water softener drain line to water heater relief valve drain line

I'm wanting to install a water softener. Can I merge the drain pipe from the softener with the line coming from the relief valve on the top of the water heater? I'm concerned about the elevation of ...
1
vote
1answer
102 views

Water heater on concrete--should I build a platform? how much heat loss in winter?

I don't know if that title the best way to phrase the question. It's winter(ish) now, and I swear the hot water just doesn't last as long as it does in, say, September. The water heater tank is ...
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2answers
47 views

Electric water heater leaks around the top, how do I fix it?

My water heater is leaking from the top around the copper fittings. It seems to be filled to capacity. Will adjusting my pressure relief valve stop my water heater from leaking? I turned the main ...
2
votes
1answer
107 views

When do tankless water heaters need to be descaled?

I had a Bosch tankless natural gas 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 fan ...
0
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0answers
43 views

Strange configuration for laundry area needs solutions

We are being given the chance to buy the house we are renting, but I have some major concerns where it comes to the laundry area. You see, the washer hookup and gas hot water tank are in a closet ...
1
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1answer
58 views

Electric water boiler .. how is the system supposed to work? (UK)

I'm not from the UK and am used to water being heated on-demand by a gas heater. Having recently moved to London, the flat has electrical heating and I cannot figure out how I'm supposed to set this ...
0
votes
1answer
77 views

Bench soldering copper pipe into a subassembly

Is it possible to pre-assemble and pre-solder copper pipes into a subassembly that then can be installed using a threaded fitting? I'd much rather solder the joints either in an oven environment or ...
0
votes
1answer
66 views

Why the huge difference in cost for Tankless vs Traditional Tank water heater installation?

I recently had my 50 gallon traditional tank natural gas water heater fail on me. It cracked and flooded my garage. After the cleanup I called out my go to plumbing company to come give me an estimate ...
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0answers
44 views

Why does the pressure relief valve on my gas water heater open at only 115 °F?

I have a new gas water heater; it is doing the same thing as my old one. The pressure relief (T&P, safety) valve will open at 115 °F or after I take a shower when the water heater is heating ...
2
votes
1answer
69 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 ...
0
votes
0answers
68 views

My water heater pilot turns off after about an hour

I light the pilot on my water heater, turn the knob to on and the burner ignites and heats water. When the burner shuts off, the pilot light goes out. About two years ago the water line above the ...
0
votes
1answer
73 views

Water heater refuses to light after power outage

I have an AO Smith FPSH 40 252 High-Efficiency gas water heater, about 14 years old. Today we had a power outage due to high winds and when the power came back on, the heater refuses to ignite. The ...
0
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1answer
172 views

PVC vent pipes or concentric vent pipes for tankless gas water heater?

I am trying to select a natural gas water heater to install into my house. It has to service two bathrooms with showers and two kitchen sinks, a dishwasher, and a washing machine. I've narrowed my ...
0
votes
0answers
38 views

Why would the water pressure seem to change after installing a new water heater?

We replaced our water heater recently and in less than 12 hours the TPV started dribbling water out of it. Shortly after the installation we noticed an increase in the water pressure when the toilet ...
2
votes
2answers
74 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 ...
0
votes
1answer
385 views

Low hot water pressure in one fixture after water heater replacement

I just had my water heater replaced (by a professional) and everything is great except the bathtub fixtures (shower head and tub faucet) in just one bathroom. The water pressure is really low, ...
3
votes
1answer
1k 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 ...
2
votes
1answer
151 views

Do I need to shut off the gas to my water heater, when I shut off the cold water intake to fix a leaking hot water faucet in my basement sink?

I need to replace a leaking hot water faucet in my basement laundry sink. To do this I need to shut of the hot water going into that faucet. The only option I see is to turn off the cold water intake ...
2
votes
2answers
96 views

Is there any harm in turning my water heater to off or to pilot for perhaps six months?

I'm finding I use almost no hot water at home (shower at gym, launder in cold; a bit for dishes) and am wondering if I can just turn the hot water tank off, or at least to just pilot, for up to say ...
1
vote
1answer
124 views

Water tank and timer (UK)

We recently moved into a small flat in the UK. For hot water we have an electric water tank with a main switch and electric timer: I made the following experiments: Main switch on / Timer on – ...
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0answers
43 views

Why is the gas water heater pressure valve leaking after installing recirculation pump & old radiator?

Kind of a complex situation. Using gas water heater as a boiler for an old cast iron radiator. In addition we added a recirculation pump. Everything was working fine but then we had leaking from water ...
1
vote
1answer
68 views

What could cause my water tank to leak only when I turn off the main water supply?

I travel quite a bit and so leave my water heater breaker off - as I travel for extended periods (months). In the past I used to leave the main water valve (near the meter) on - and would turn off ...
1
vote
1answer
176 views

What's causing the smell in my basement?

I suspect my natural gas water heater is filling the basement with an off-putting odor similar to what it smells like when someone gets a perm. I guess you could say its like the sulfur/rotten egg ...
0
votes
1answer
27 views

Rust in gas flame area of water heater, should be replaced?

There is rust right above the gas flame in our water heater (not outside the water heater as in this question Rust spots on water heater -- time to replace? or on the inside where the sacrificial ...
2
votes
1answer
46 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 ...
0
votes
1answer
316 views

Why does my hot water smell like wood smoke?

We live in MN, in a house built in 2008 (and our water heater, installed in the basement, is about that vintage). For the past few weeks, I'm detecting a smoky smell from the hot water out of a ...
0
votes
1answer
2k views

Why is my water expansion tank leaking?

I live in the northeastern US and we just turned the heat on (oil) and this morning I went down to the basement and saw this: The water is coming from the plumping above something labeled "water ...
0
votes
2answers
518 views

Using PEX for a water heating system

I am replacing my existing faucet plumbing with red / blue PEX all over the house. Everything that goes to the sink, dishwasher, washer, bathroom sink and so on will be color coded and installed ...
0
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1answer
54 views

What could cause my electric water heater to over heat water?

About a year ago our 15 year old electric water heater heated the water nearly to the boiling point until the breaker on the tank shut off the power. When I reset the breaker the temperature went ...
0
votes
1answer
63 views

How to measure water pump pressure in a spa heating system?

Short version (TL;DR): how can I measure the output pressure of a water pump in a spa heating system and verify that it is within the gas heater input pressure specs? The Whole Story I'm trying to ...
0
votes
1answer
861 views

Why is boiling hot water coming out of every faucet, and even the toilet?

Help! I live in a 80 unit condo (8 floors), with hot water tanks on the top floor (4). They flow down 13 different lines to different units and hot water is recirculated through recirc pipes. ...
3
votes
2answers
74 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 ...