Snowbird home prep, hot water heater

We just disconnect the thermostat wire for the water heater zone.

I had a problem of the boiler pressure getting too low with the main water turned off. Blew one of the circ pumps. The solution is to run a separate line to the boiler and put a whole house shutoff after that. If you do this, make sure you do something with the PT valve overflow (like pipe it to a sump or a drywell with a sump pump). I had an expansion tank diaphragm rupture and it put and inch or 2 of water in the basement in 20 minutes. Can't imagine that going for a month.

My mother's house has an oil furnace hot water boiler system, with the heating water pipes that run through the house. The system is dependent upon a supply of fresh water coming in all the time. There is a valve that opens if the water level in the heat system drops below a certain point, then fresh water is infused into the system, keeping it constantly free of any air.

If your's is the same way, and you are leaving the heat on in the house, even at 55 degrees, you may want to rethink turning the water off completely.

If the water heater has no dependency on the furnace boiler, and the furnace boiler has no dependency on the water heater, then just turn the power off to the water heater and let it go cold. It won't hurt anything.

IF there is no dependency for the fresh water into the boiler system, then yes, go ahead and turn the water source off and STILL turn the water heater off.

If for some reason the water heater were to over-heat and the relief valve blew and you were not there, the heating element (if electric) or the flame (if propane) will continue to heat the water and now you have air in the tank. It's a boiling bomb waiting to blow. Chances of this happening are slim, but why take chances. Just kill the power or gas to the water heater and keep it safe.

(And FYI! I've been dealing with my mother's house ever since I was born! I'm now 62 and I absolutely hate that furnace system in her house. About 30 years ago she had the furnace replaced and went with another boiler system. I so much tried to persuade her to switch to a forced air system and get away from all those water problems, circulating pump problems, cleaning out that boiler soot form burning fuel oil, bleeding the lines and replacing parts over the years!)

I always turned the water heater off. Never turned the main water off did turn washer water off. FA gas furnace at 55. Vegtable oil in P traps keep them from drying out. Good neighbor to keep an eye on things. No problems in 3 years.

I got rid of my hot water house heating system - it's now forced air propane fired. I turn off my well pump and drain the water pipes including the water heater.

jplante4 wrote:
We just disconnect the thermostat wire for the water heater zone.

This is what I was thinking about.