Heating Unused Rooms? How to Turn Off Heat

LESLIE: Charlene in Idaho has a question about heating. What can we do for you?

CHARLENE: I heard it said by energy experts that if you’re not using a room to shut off the registers and I was told by another person that if I shut off the registers, I was – it would be detrimental to the actual heating unit; I’m a little bit torn. Which is it?

TOM: Here’s what you want to do, Charlene. You can shut off those vents in the rooms themselves but a more effective thing for you to do is on the duct that leads to that, there’s probably a damper built into the duct and …

CHARLENE: Right.

TOM: … it’s easier to turn the damper off, which will completely seal that off. It’s more effective than just the louvers that are on the heating register itself. No ill effects from shutting that off. Obviously, if it’s near plumbing, the room gets cold, you could have freezing. You know, I presume that you’re not going to do this in any room that has a thermostat in it that controls the function of the heater.

But simply shutting them off at the dampers on the vents leading there is not going to have a terribly adverse effect on the heating system itself. The heat is only going to run as long as it needs to, to satisfy the thermostat and whether it distributes to all the rooms or not is immaterial.

LESLIE: OK. So by shutting off the damper, it’s not just redirecting all of that forced air that would have come into that room into, say, the neighboring room.

TOM: It’s going to basically take as much air as is supplied by the blower. Now, let me think about this. Could it maybe be a little bit faster? Probably not because it’s only going to run as long as it needs to, until the thermostat is satisfied and it’s going to shut off. If the air speed goes up, it doesn’t really matter.

LESLIE: OK.

CHARLENE: The thermostat is in the hallway, so I noticed that when I did shut them off, the heater didn’t go on as much because the rooms that we were heating stayed warmer.

TOM: Right. And it probably heated up more quickly, too.

CHARLENE: Yeah. OK. Well, thank you very, very much. I sure appreciate that.

TOM: There you go, Charlene. Good luck with that project. Thanks so much for calling us at 888-MONEY-PIT.