My gas hot water heater seems to be firing almost constantly. The heater is in the kitchen and the floor leading from the kitchen to the bathroom (a slab) seems warm to the touch. Also, just recently the cold water faucet in the kitchen runs hot for a few seconds.

What is the temp setting on your heater? It is possible for a heater to push back a small amount of heated water back into the cold line. It depends of how close the cold line split is to the heater. Can you get us a temp of the water running out the hot sppigot after a few minutes, you may have a bad thermostat.

Thanks. I'll try to get the temp. (the water heater is actually at my daughter's, so I'll have to go there). Would a bad thermostat keep hot water in the pipes all the time? I think she turns the setting down after their morning showers.

Connie1:

If you think the heater is running at an almost constant rate and the bathroom slab seems "warm to the touch" then I would have you shut all faucets/water sources off 100% and then I would have you check the RED ARROW on your water meter and see if it moves. Sometimes there is a meter within the meter window with a smaller red arrow. It is this smaller red arrow that you want to watch... ;) Give it some time as some meters read differently.

If it moves then there is a leak under the slab and this will need to be dealt with promptly!

We can discuss turning on/off thermostat after we deal with this... O.K.?

MARK

.

Thanks. I will check this out tomorrow, but if her meter is like mine, it doesn't have anything that resembles your picture on it. Just a thermostat. We are in California and maybe our meters are different here. I'll look at it though.

Connie, that meter you see in post #4 is not on your heater, its is your water main meter. If it moves when all fixtures are off you may have a leak under your floor.

ballengerb1, thanks for that info. Unfortunately we in Fresno are not on water meters (isn't that ridiculous?) so I can't follow that advice.

If you think that the hot line is leaking under the slab and you don't have a water meter as Mark suggested to check, I would suggest to close the cold water shut off valve to the heater, open the hot side of the faucet until the water stops running, give some time and check if your water heater stops firing, if it does then you defiantly have a leak under the slab where it gets hot, good luck.

John

Hi Conn1e: Do you have a hot water circulation system installed on your plumbing ?

Is water free in your town? It must be metered somewhere I would think.

Connie: you most likely have water meter. Water meter is installed by the curb in front of your house. It is covered with small concrete trap door.

Ballengerb1, no the water is not FREE, but it is billed at a flat rate dependent on lot size. The city is in the process of installing individual meters. I appreciate all your help and I am working with my daughter to try to get to the bottom of this. She has found very wet ground outside the bathroom so wonders if the leak is there.

Sounds like a plan.

Not much doubt in my mind that you have a hot water pips that's leaking. Most likely from a bathroom fixture. What fixtures are on that outside wall? Your daughter may not pay for all the extra water but she's for sure being billed for the gas. Whadda you want to do now? You can call a plumber and he'll most likely take up the slab to repair the leak, **OR** you could dig down beneath the foundation and try to tunnel to the leak and repair it without going through the slab. Your choice!
But first find out for sure. Close down the cold water inlet to the heater overnight and check the warm spot in the slab in the morning. If it's cooled down then you ,indeed , have a leak. Like I said, There's no doubt in my mind but I want something more to go on then a strong hunch. Good luck and let me know the results. Tom