Leaving a Heating System
What to do about the baseboards before you head out on vacation
We live in a ranch home with a baseboard hot-water heating system. I was wondering if we should do anything when we leave for a winter vacation.
— Paul, Stony Brook, NY
Richard Trethewey replies: The greatest risk you face involves water damage due to the supply pipes leaking or bursting, especially after a hard freeze.
Closing the main water valve is a good strategy for preventing your house from being turned into a swimming pool when a pipe bursts or a clothes-washer hose splits. That way, water damage will be limited to whatever's already in the pipes. If you want to be extra cautious, you can drain the potable water system, too.
Your heating system is separate from the potable water system, but if you drain it, too, you won't have any way to heat the house. Then you'll have to drain everything to prevent freeze damage. That means toilets and traps, the humidifier (if you have a furnace), the pressure tank (if you have a well), the dishwasher pump, the water softener, the fish tank, the lines feeding the automatic ice-cube maker in your refrigerator.... You get the idea. To avoid all that, I'd suggest that you leave the boiler on and just set the temperature back to 50 degrees or so.
No matter what you do, have someone check on the place every week, then every couple of days or so when freezing temperatures are likely. Some homeowner's insurance policies won't even pay for damage caused by leaks or other system failures unless the place is checked regularly. You can also have the house fitted with a temperature monitor that automatically dials an emergency number if indoor temperatures drop too low.