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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24
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2answers
41k views

What temperature should I set my water heater to?

When adjusting my water heater, what temperature should I set it to? Is the answer different if you have: Concerns about diseases A dishwasher Young children or elderly that can be easily burned ...
1
vote
2answers
162 views

50 Amp tankless water heater and 30 amp double pole switch

I just moved into a house. I have a 50 amp max tankless water heater. The circuit breaker is 50 amps. The water heater is connected to a NEMA 10-50 power receptacle. There a switch to turn on and off ...
1
vote
1answer
60 views

shower shock,when hot or cold water is used in other parts of house

our 2 showers, we can't run any other hot or cold water without get extreme hot or cold differentials while in the shower.bought house last year,built in 1985.
0
votes
1answer
53 views

Does a water heater have to be completely full for the water to heat?

We installed a new water heater and it is not hot. We think it is full. Does a water heater have to be completely full for the water to heat? We think we may possibly have a leak in the hot water ...
1
vote
1answer
47 views

Draining Water Heater

Recently, my water heater started leaking from the top edges. I can see rust lined up all along the outer rim on the top, and water is very slowly trickling out. I've made an appointment with a local ...
2
votes
3answers
4k views

Properly venting a gas water heater

Ahh, the joys of an old house. The former owners of my house did some funky stuff with venting the water heater. Let me explain: the water heater is in the basement there is a 3 in single walled ...
0
votes
1answer
216 views

Will an inline tankless heater help my 50 gallon water heater fill my 70 gallon tub?

I've been working on an issue with my remolding plan. I want to get a 70 gallon tub, but I currently only have a 50 gallon water heater. The water heater is only 2 years old and is fairly nice, but ...
0
votes
2answers
134 views

Is this a Direct Vent Water Heater?

My contractor asked me to choose a direct vent water heater and have it delivered. I (generally) understand the difference between direct vent and power vent, having read up on how they both work. ...
0
votes
1answer
382 views

How hot should my hot water heater vent get?

My gas hot water heater's flue/vent is very hot to the touch. Is that normal? How hot should it get?
2
votes
2answers
634 views

Do I need a regulator to connect a tankless water heater to a 20 lb. propane tank?

I am going to hook a tankless water heater to a 20lb propane tank. Do I need a regulator coming off of the propane tank?
0
votes
2answers
75 views

Need help understanding gas water heater

I just bought a house and it have a gas water heater. I need to know what is the water shut off valve to shut down water in the entire house. Also if you can help me label any of the other knob (which ...
0
votes
1answer
161 views

Water Heater Gas B-Vent Install

I installed a new water heater and want to vent it right. The old water heater used ABS pipe since it had a blower. Basically I have a 3" b gas vent pipe coming in and connecting to a flex gas pip ...
0
votes
1answer
32 views

Water Heater PRV keeps opening

I have a water heater that is 20 years old. When we turn up the water temp the pressure release value opens and drains water into the overflow pipe. The issue is this then overflows from the top of ...
0
votes
3answers
65 views

How should I install a new water heater?

I have recently shifted to San Diego. I am planning to install my own water heater. Can anyone guide me on below questions: Should I place my water heater next to furnace? Should I have a common ...
1
vote
1answer
365 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
0answers
26 views

Solar water heater size

I want to build my own solar water heater. It should heat about 20-30l of water per day to about 60°C. There is about 4-5h of direct sunlight to the place I thought of putting it. How big should my ...
1
vote
1answer
104 views

Why do high efficiency water heaters require outside air vents and drains?

All high efficiency water heaters seem to require PVC air intake and vent; the existing water heater I have doesn't have a drain connection or intake vent; only a traditional chimney. What are these ...
0
votes
1answer
34 views

water heater vent

In the water heater closet, the water heater is vented through the roof. There is a vent pipe that goes through the floor in the same closet. What would this vent pipe be for and can I cap it off as I ...
3
votes
1answer
112 views

Dropped Item in hot water heater

When I was redoing the plumbing to my hot water heater I accidentally dropped a pen cap down the vent stack/flu. Will this cause any problems? Like melting or catching on fire? Its going to take a ...
4
votes
1answer
375 views

How bad is it to attach a gas water heater to a gas furnace electrical circuit?

I'm looking to replace my existing water heater with a more efficient model. One of the things that makes better models more efficient is the replacement of the thermocouple / pilot control system ...
0
votes
0answers
35 views

Do I need to replace the thermal expansion tank when replacing a water heater?

I'm considering replacing my water heater. My existing heater has an expansion tank attached to the top; should I look into replacing that at the same time or is the life expectancy on those longer?
1
vote
2answers
99 views

How do I know when my water heater should be replaced?

The condo I just moved into has an original 2001 gas water heater that is missing a few features one would like to see in 2015, such as inspectable anodes. The home inspector pointed this out as a ...
0
votes
2answers
100 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?
0
votes
1answer
146 views

Hot water tank leaking at bottom could it go from a trickle to a gush?

My 20 yr. old gas water heater that's located in my basement has had a slow leak for 6 mos. My husband doesn't feel the need to replace it yet and feels we can just continue soak up the water with a ...
0
votes
0answers
114 views

water temperature varies in new hot water heater

I have a new house with a gas water heater and a recirculating hot water pump to have instant hot water at all faucets, My water temperature varies from luke warm to very hot. Some times the TP valve ...
3
votes
1answer
2k 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 ...
1
vote
1answer
83 views

A line T-ing off my water heater drain line. What might it be for?

There is a line T-ing off of the DRAIN line at the bottom of my water heater and I don't know what it is for. It is UPSTREAM of the valve that I need to open annually to remove sediment from the ...
0
votes
1answer
61 views

Feedback on why constantly draining. It's starting to flood backyard

There's no leakage near/ around water heater. No slime or build up of any kind. But there's constant hot water drainage coming out through pipe in backyard. It's starting to flood back porch area. ...
2
votes
3answers
20k views

What can cause an electric water heater to stop working?

Last night my electric water heater stopped working and I'd like to figure out whats wrong with it before going off and calling a repair service. What are some things I can do to troubleshoot this? ...
3
votes
3answers
11k 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 ...
1
vote
0answers
57 views

water heater won't stay lit

Looking for suggestions on repairing my water heater. The pilot light won't stay lit. I've cleaned the air intake and checked the venting in the attic but it didn't correct the problem. It will ...
0
votes
2answers
92 views

What is the function of this electric part on my unvented water heater cold water inlet?

Does anyone know what this electric part does? In the photo it's the black plastic block device attached to the pipe on the right hand side (which is the mains inlet to the heater; the left is the hot ...
0
votes
2answers
59 views

How to ensure that water heater is mostly on or mostly off?

My friend just rented an appartment (in the UK), and during the inventory the janitor showed her the programmable water heater, and said it was configured to turn on for a few hours during the day. ...
1
vote
3answers
12k views

Why won't my pilot light stay lit on my hot water heater?

I have a reliance model 5 30 NORS971 gas HOT WATER tank. The basement flooded a little and put out the pilot. When it would not light, I replaced the pilot tip and went ahead and replaced the ...
0
votes
1answer
86 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 ...
4
votes
1answer
875 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
0answers
35 views

New water heater, now shower goes cold if hot water is used anywhere else in the house

We just replaced a 40 gallon water heater, power vent. The plumbing company said upgrading to code was needed for the plumbing of this water heater. We replaced it with an almost identical model, ...
1
vote
0answers
50 views

Could my water heater be causing an electric system failure?

My water heater, a Styleboiler VF 100 SE (1200W), has never had any problem. Recently I bought an electricity timer plug (up to 3500W) to put its plug into, in order to dose the amount of electricity ...
3
votes
1answer
682 views

Pressure problems with oil boiler

I've been having continued problems with the pressure in my home oil boiler rising to 30psi over time (and then leaking out the pressure relief valve). Technicians have examined it multiple times but ...
2
votes
1answer
180 views

Can turning up the temperature of a water heater damage it?

I've got a 40 gallon water heater, and what I've been finding is that it provides just enough hot water to fill my sizable bathtub, but no more. Which means if I want to rinse off with the shower ...
1
vote
1answer
133 views

How can I check my hot water heater temperature? Isn't 120 degrees cold?

I'm trying to test the temperature of the hot water coming out of my hot water heater but I'm very confused. Can I use a meat thermometer or what should I be using? Also, just to make sure my ...
1
vote
1answer
9k views

How should I connect nipples to a hot water heater?

I recently installed my new hot water heater. I know nothing about plumbing and my installation procedure was informed only by sketchy home depot employees and youtube. One of the issues I'm having ...
3
votes
2answers
130 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
vote
0answers
65 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 ...
1
vote
2answers
3k 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 ...
0
votes
1answer
44 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 ...
5
votes
3answers
5k views

How do I prevent harmonic resonance hum in PVC vent of newly installed hot water heater?

I just had a new power vented water heater installed (HTProducts Phoenix Light Duty) in our crawlspace. The contractor that put it in used part of the existing 3" concentric vent from the furnace we ...
2
votes
2answers
1k views

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

We have a Navien on demand 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 way ...
0
votes
1answer
65 views

Should I unplug the timer on the water heater when shutting off water to the house?

If I shut the water off to the house, do I need to unplug the timer on the water heater?
0
votes
1answer
114 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 ...