I would like to know if I go away for two days and shut my main water shutoff valve can I leave my gas hot water tank on. I saw two answers
to a similar question and one answer said you can leave it on and the other
said you had to shut it off. I am confused now as to whether I can leave the gas hot water tank on when I shut the main water valve?

letmetellu

Turn off the main water shut off and then turn the thermostat on the water heater to the lowest position on the dial, some even have a setting for "vacation" if you have that turn it to that position. Then use the knob on top of the thermostat to the pilot position. When you return turn the tempature up to your normal setting and then turn the top knob to own.
Doing this should insure that you water heater will not heat while you are away.

jersey-joan

If I was away and shut my main water valve off and left my gas hot water tank on and it burst and the water drained out would the pilot light go out and if it did then would the gas would be leaking and possibly explode? I have an A.O. Smith Model FGR 30 224 with no manual from the previous homeowner and I don't know if it would automatically shut off the gas flow were the pilot light to go out.

speedball1

Hi Joan,

Set your mind at ease. Water heaters have all sorts of safety features built in. if you went away and left the gas on and the water off the water would heat up to the desired temperature and then shut the burner off untill the water cooled down. But say you had a faulty thermostat and the water turned to steam. The T & P (temperature and pressure) relief valve would open up and relieve the pressure. So, no big boom!

Now say the tank developed a leak and the water doused the pilot light. The thermocouple would turn off the gas and shut down the pilot light.
So your fears are foundless. Enjoy your vacation. Regards, tom

DaPlUmBeRGuY

as an expert licensed plumber myself... I say that speedball hit it on the head ! no fear he's right your safe