ENERGY STAR room AC sizing chart
| Area to be cooled | Capacity needed |
|---|---|
| 100 up to 150 sq ft | 5,000 BTU/h |
| 150 up to 250 sq ft | 6,000 BTU/h |
| 250 up to 300 sq ft | 7,000 BTU/h |
| 300 up to 350 sq ft | 8,000 BTU/h |
| 350 up to 400 sq ft | 9,000 BTU/h |
| 400 up to 450 sq ft | 10,000 BTU/h |
| 450 up to 550 sq ft | 12,000 BTU/h |
| 550 up to 700 sq ft | 14,000 BTU/h |
| 700 up to 1,000 sq ft | 18,000 BTU/h |
| 1,000 up to 1,200 sq ft | 21,000 BTU/h |
| 1,200 up to 1,400 sq ft | 23,000 BTU/h |
| 1,400 up to 1,500 sq ft | 24,000 BTU/h |
| 1,500 up to 2,000 sq ft | 30,000 BTU/h |
| 2,000 up to 2,500 sq ft | 34,000 BTU/h |
The chart assumes an 8 ft ceiling. Then make these adjustments:
- Heavily shaded room: −10%
- Very sunny room: +10%
- More than two people regularly in the room: +600 BTU per extra person
- Unit used in a kitchen: +4,000 BTU
Tips for choosing a room AC
- Measure the room you actually want to cool. Open doorways to other rooms add to the area.
- Compare the CEER rating: the higher it is, the less electricity the unit uses for the same cooling.
- Check the plug: some larger units need a 208/230 V outlet instead of a standard 115 V one. It is listed on the spec sheet.
- Install window units level side to side with a slight tilt outward so condensate drains outside.
