What is the formula for calculating the proper size window air conditioner for a two story split level house?

Question

What is the formula for calculating the proper size window air conditioner for a two story split level house?

Answer 1

Measure the Room

Determine the square footage of the room (multiply length x width).

There are lots of variables to consider when choosing a room AC — number of windows, number of people in the room, which direction the room is facing, ceiling height, etc. Energy Star has this chart on finding the right size room air conditioner to meet your needs.

Area To Be Cooled

(square feet) Capacity Needed

(Btu's per hour)

100 to 150 5,000

150 to 250 6,000

250 to 300 7,000

300 to 350 8,000

350 to 400 9,000

400 to 450 10,000

450 to 550 12,000

500 to 700 14,000

700 to 1,000 18,000



Remember – bigger is not better. A unit that’s too large will cycle on and off too frequently, using too much energy and causing unnecessary wear on the electrical components.

Measure the Window Dimensions

Most window air conditioners are designed to fit double-hung windows. Measure the inside dimensions (the lower part of the window that raises). Take an exact measurement, not just an estimate.

Take your room dimensions and window measurements with you when you go shopping.

Answer 2

I have to agree with Sensible.

  12,000 BTU equates to 1 ton. 1 ton equates to anywhere from 500 to 700 sq. ft. of space, certainly depending on the layout of a house, insulation, number of windows, etc.

  I want to assume you realize that heat rises, and a second story, should have additional plug in units, and/or in the case of central, perhaps even a second tonnage unit, for the upstairs.

Steven Wolf

Just my two "sense"

Answer 3

I am not aware of any window unit that will cool a split level home. I had an 18,000 BTU unit (220 volt) and it had a hard time with 3 upstairs bedrooms that were small.

Answer 4

http://www.csgnetwork.com/acroomsizecalc...