Any plumbers in the house?

pjrocco · #1

Ever since I moved into my new house in June I've had an issue with my hot water heater. If it's not used within 6 to 10 hours the water get cold. On the other side once it turns on the water gets unbearably hot. I have done some research and found nothing on the problem except to buy a new hot water heater. Is there an automatic shutoff switch or something like it to conserve gas? Or is this thing on it's way to breaking?

Thanks in advance!

poodle · #2

how old is the tank

pjrocco · #3

poodle wrote:how old is the tank

The house was built in 2004 so I'm assuming it's the original.

boxer93 · #4

Hi Rock,
Not a plumber by trade, but I have done the plumbing in my house for the last 20 years. If it was 2004 It may still be covered by a manufacturers warantee. You also don't state how large the tank is. If it's undersized/oversized for the house you may get the hot/cold type symptoms. One thing to check would be the thermostat of the tank. You mentioned gas. Is it a gas fired tank? Also is it possible that you have a tankless water system? I don't have gas experience, there may be a energy saver option. Mine is actually heated from my houses furnace and my issue once was a circulator motor. Other than the motor I've not replaced the water tank in my house in the 20 years I've been there. Not sure if this helps. Good Luck.
Chris

4 s ter · #5

Rock

Sounds like you have a defective thermostat.

The thermostat senses when the tank drops below a certain pre-set temperature and causes the burner to come on. When the desired temperature is reached, the thermostat shuts off the burner. If the thermostat is defective it won't turn the burner on and off correctly to maintain the water temperature within the desired range.

You could check the manufacturers website or 800 number - this information should be on any documentation which came with the water heater (and which the builder/plumber should have left with the heater.

Unfortunately, servicing gas hot water heaters is best left to qualified technicians.

yablanowitz · #6

Yep, it sounds like a bad thermostat, which would require draining the tank and replacing the gas valve (the t-stat is integral and the whole unit is sealed). Most water heaters have a three year warranty these days, so a call to the manufacturer is definitely in order.

ken · #7

pj-

I would doubt that the water heater is bad and it sounds like it has a bad thermo-coupler not the thermostate. An easy fix. Home depot or any home supply store or plumbing store will have these. It looks like a small tube that runs from the gas valve to the pilot light. It is what controls the gas valve to open.

goodluck,
ken

J Smith · #8

Well it could be several things.
Be sure to get it checked fast,if it is getting to hot you could end up have the pop off valve blow.Trust me,thats a mess.
Mine is a 42 gal electric and the last time I had trouble with it I found that it was cheaper to buy a new one at Lowes for 200.00 than to fix the old one.

Fred Sanford · #9

I was/am a plumber. I did plumbing for about 8 years before I changed to the IT field. I still do all my own plumbing in my house and for other folks that I like.

It's a bad thermo-coupler as 'ken' said. Easy fix, if you are into fixing things yourself. Since your water heater is still under warranty just have it replaced.

If it was new in 2004 it will have either a 5 or 10 year warranty. Call the builder and see if he will have a plumber replace it for you.

By "replace" I don't mean the entire tank....only the thermo-coupler.

Fred Sanford · #10

I'm a plumber. I worked plumbing for 8 years before I got into IT.

Sounds like a controller going bad. If the thermocouple was bad it would be shutting off the gas valve. It also may be a newer one without a pilot lite.

Either way since it's only 2 years old call the builder and have them send a plumber out to look at it. Most water heaters have either 5 or 10 year warranties. The controls sometimes only have a 1 or 2 year warranty on them.

It could be the thermocouple or the controller. If I had to put money on it I would bet it's the controller. If it's free to have them come look at it just do it.

yablanowitz · #11

David, you are correct in saying it can't be the thermocouple, as a bad thermocouple would prevent it from staying lit, resulting in cold water at all times. The closest thing to these symptoms I have ever seen was when a 12 year old water heater had built up enough calcium, sand and other stuff to bury the temperature sensor inside the tank. The fire would heat up all the crap in the bottom of the tank, which would continue heating the water long after the fire shut off. The T-stat was set for 130 and actual temperature at the kitchen faucet was 190 :eek:

The only way I can see that happening on a two year old unit would be with a bad water well that dumped a BUNCH of sand in it.

P.S. I've been doing this stuff for 25 years :D

Fred Sanford · #12

yablanowitz wrote:David, you are correct in saying it can't be the thermocouple, as a bad thermocouple would prevent it from staying lit, resulting in cold water at all times. The closest thing to these symptoms I have ever seen was when a 12 year old water heater had built up enough calcium, sand and other stuff to bury the temperature sensor inside the tank. The fire would heat up all the crap in the bottom of the tank, which would continue heating the water long after the fire shut off. The T-stat was set for 130 and actual temperature at the kitchen faucet was 190 :eek:

The only way I can see that happening on a two year old unit would be with a bad water well that dumped a BUNCH of sand in it.

P.S. I've been doing this stuff for 25 years :D

Yeah, I've also seen the mineral build up ruining the sensor. I ruled that out seeing as it's only 2 years old.

Of course, this is just best guessing without seeing the tank. :)