Keeping the pipes from freezing...

John MacGregor

Hello,

I've heard conflicting reports on how low I can set my thermostat when I'm not around. I have a one pipe steam system powered by a gas boiler...I'd like to save a few pennies by not heating my place when I'm not there/asleep but I don't want to set it too low that my pipes might freeze! Keep in mind I live just outside of Boston...

I've read that you'll only save money if you set your thermostat back by at least 10%...so if I keep it at 70 degrees when I'm there, I should set it back to 63 when I'm not. Is there a general rule that you guys go by?

~Jenny

Constantin

Should work fine with one-pipe steam

As long as you don't mind waiting for the place to heat up, go ahead turn down your thermostat to 60°F. Just be sure that no part of the house freezes under those conditions.

For example, be particularly careful with sinks and other water lines inside cabinets in unheated kitchens that are on exterior walls. These spaces can get very cold when the cabinet doors are closed. The solution: Keep the doors under the sinks open so the warm air from the rest of the apartment can circulate in and out.

IIRC, a 1% reduction in energy needs occurs for every 1°F you turn your thermostat down from 70°F. There is a neat article on the Old House Web Archive going into some detail on this.

Jay_11

Water Line

I have water lines to the second floor bathroom that run along the kitchen exterior wall that froze last year when the interior of the house was at 63 degrees. Does it help to leave the faucetts to this bathroom at a slow drizzle so the water keeps moving?

Constantin

You may be better off...

... buying one of the recirculation systems like the ones sold by Grundfos (IIRC). Basically, a little pump ties the hot and the cold together below the sink and recirculates water through the hot and cold side of the potable water system until the hot side reaches a certain temperature.

If the hot side is maintained at 90°F, there should be enough heat locally to prevent freezing.

Jay_11

Thanks for the idea. I'll run it by my plumber.