Air Conditioning BTU confusion

May 28, 2011 9:54 PM

What size (BTUs) air conditioners should I buy for my (sort of) open layout apartment?

Our apt has an identical layout to this apartment, though a few feet bigger in all directions, and a pass-thru section between the kitchen and the living room. Our plan is to install 2 window ACs, one in the BR and one in the LR. The LR AC will need to compensate for the kitchen pass-thru and the BR AC will have to handle the bedroom door left open at all times (damn cats). So, how many BTUs for each? I'm thinking slightly larger for the LR but I'm unsure about numbers.

posted by ranunculus to Home & Garden (4 answers total)

size wise, our house is similar. We have a 6000 BTU in our bedroom, which seems to be enough. In our living room (20X24) our 10,000 barely cuts it, and in fact doesn't quite do it between 2:00 and 6:00 p.m. All we have is a 110 volt outlet and 10,000 is about the top we can run. This is FL, so pretty extreme test of an a.c. unit. We dread July and August. See if you can get a 220 outlet and get as big of a window unit you can. fans are a big help too, in your case even more then mine, to cool your kitchen. You also might consider a 10,000 unit, with a portable a.c. unit to suplement on the more sweltering times of the day.
posted by Redhush at 11:47 PM on May 28, 2011

IANYME(I am not your mechanical engineer) I would get a 6000 BTU (1/2 ton) in the bed room and a 9000 BTU (3/4 ton) in the living room. Rule of thumb. Take the square footage and divide by 400 to get the tonnage required. In the northeast. Ignoring ventilation air.
posted by ihadapony at 1:26 AM on May 29, 2011

Any air conditioner sales department will be able to figure out your needs from measurements and a photo.

It's better to get an A/C slightly too small than slightly too large, and getting one a lot too large is self-defeating. One of the big benefits of A/C is reducing humidity. Using a smaller unit means that it's pulling out humidity most of the time, while a bigger unit simply cools the air while leaving the humidity high.
posted by KRS at 3:23 PM on May 29, 2011

The biggest units that your electric circuit can handle
posted by caddis at 4:50 PM on May 29, 2011