Temperature Difference Between Rooms: How to Fix Uneven Heating and Cooling
LESLIE: Now we’ve got Corey in Michigan who is dealing with an addition that’s having a hard time maintaining its heat. Tell us what’s going on at your money pit.
COREY: I purchased a foreclosure a couple years ago and they put an addition on the back of the house. And the house has a basement but there’s a crawlspace under the addition. And I’ve noticed the past couple years that I’ve been here – the addition in the back, it’s just one room. It’s like a great room; it’s about 18×20 feet. And it’s always colder; it’s around 10 to 15 degrees colder than the rest of the house.
LESLIE: And what type of heating do you have in that space?
COREY: We have forced-air heating throughout the house and they put an additional duct going to that room. And we also have a gas fireplace in the back. But unfortunately, I’m always finding myself having to put the fireplace on to try and even out the …
TOM: So, did they try to extend the heating system from the main house into the addition?
COREY: They did. And that was part of my concern when I was looking at it, because they ran a duct right off of the main duct off the furnace.
COREY: So, I was thinking maybe kind of like how air would take the path of least resistance, it’s just continuing through the large duct and not really being forced into the smaller duct that goes right into that room. Because the furnace is actually very close to that room.
TOM: So it sounds like what they tried to do is take the inexpensive way out, which is to extend the existing heating system into that room, which may or may not have been properly done. So, have you had an HVAC contractor look at this and look at the duct runs?
COREY: No, I haven’t, no.
TOM: Yeah, so I would do this: I would look at the duct runs first and see if the duct system can be adjusted or additional ducts can be installed to get more air into that room. You need more heat in that room. That would be the least expensive way to go. If you’re running this gas fireplace to try to balance off the chilliness in that room, you might want to think about – because we’re just sort of working with – I guess the coldest days is when you need this, I would imagine? You might want to think about adding electric baseboard heat.
Now, we almost never recommend that because it’s the most expensive but in a situation where you’re trying to add supplemental heat to a room, that’s not a bad way to go, because it’s inexpensive to install and you’re only going to run it when you really need it.
COREY: OK. OK. What do you think about maybe putting like – I know they have those fans that you can stick inside ducts to maybe help pull the air into the duct?
TOM: I wouldn’t go that route until I had a good HVAC installer – not a service guy, not a guy who just tunes up furnaces but somebody that really knows how to lay out a duct system for a house – look at it. That’s called a duct booster. It might be an alternative; it might not. It depends on how the duct was put together, how much supply air and return air is getting back.
Because remember, you can’t just throw the air in there. You’ve got to pull the cold air out of there and send it back to the heating system. So if they’ve just got supplies and no return, that could also be an issue.
COREY: OK. Yeah, there is a return but yeah, it’s – I don’t know. I’m not sure exactly how many corners they cut, because I know in the crawlspace there, they didn’t put no Visqueen down or anything like that, also.
TOM: Yeah, well, I would talk to an HVAC contractor about the duct layout, see if you can get some additional feedback on that and then just look at all the alternatives. What’s it going to cost to get the duct system working right? Can it work right? Is the existing furnace big enough to supply the amount of heat that that room is going to need, given its location, given how much glass is there and so on? And remember, keep that as a fallback position that you could always add electric baseboard to supplement what you have.
COREY: Oh, OK.
TOM: Alright, Corey. Well, good luck with that project. Thanks so much for calling us at 888-MONEY-PIT.