LESLIE: (chuckling) Whoo, well it has been one hot summer and Keith in Virginia, listening in on WJFK, doesn’t have a very nice air conditioning situation. Tell us about it. What’s going on?
KEITH: The air conditioning is very cool in the basement, it’s OK on the first level and hot on the second level. So it’s not reaching the second level.
TOM: Now you have central air conditioning?
KEITH: Yes, I do.
TOM: Is the furnace and air conditioning unit in the basement?
TOM: So you’re trying to push that air up two stories.
TOM: Alright, that’s part of the problem. Do you have supply and return ducts in each room or is there a centralized return duct?
TOM: OK, that’s another part of the problem.
KEITH: Actually, I think there’s only one.
TOM: The problem here is, Keith, is that you’re not moving enough air upstairs. And the way to solve that is to improve the – is put additional ducts in. But a more practical thing would probably be to put in a second zone upstairs and allow that unit to only cool the first floor and put a second zone upstairs. That’s going to give you the best balance; most balanced air conditioning system. It’s very common when you have your furnace and air conditioning unit located in the basement that it’s very hard to push up that air two stories and get the second floor to cool nearly as well as the first.
KEITH: Because I’ve taped vents and everything trying to – I’ve actually closed the vents in the basement and on the first floor.
TOM: Yeah, you may just be pushing the system as far as it’s going to go and this may not be big enough to give you the BTUs that you need in cooling power to do that.
KEITH: Oh, you think so?
TOM: And the best way to do it is to put a second zone in on the second floor.
KEITH: Second zoning?
TOM: Second zone on the second floor. Yeah, second set of air conditioning equipment. You’d have an air handler instead of the furnace because you wouldn’t need the heat. You’d have an air handler probably located in the attic and then you’d have a second compressor outside.
KEITH: Oh, I see.
TOM: And you’d drop some ducts through the ceiling of the second floor and that would make it super comfortable.
LESLIE: Tom, what would be the more cost effective decision? Adding in that whole second zone or upgrading the compressor unit for the first system to a larger unit to accommodate more?
TOM: That wouldn’t buy you anything.
LESLIE: It wouldn’t do anything.
TOM: You could have more cooling power but you don’t have enough airflow. This is a game of airflow. If you don’t have enough airflow, enough cooling air going out and enough return air coming back, it’s not going to cool the second floor. So that’s why you’re better off putting in a second zone upstairs where you can really move a lot of air across the coil and that will actually cool it and make it much more comfortable for you, Keith.
TOM: Why don’t you get this system serviced by an HVAC contractor, talk about your problems and see if they have any solutions because there may be some adjustments to the duct system that will be less expensive than putting in a second zone that could fix this as well.
KEITH: OK, alright. Well, great. Thank you so much.
TOM: You’re welcome, Keith. Thanks so much for calling us at 888-MONEY-PIT.