AC size for a 2,500 sq ft room
50,000 BTU
for a 2,500 sq ft room (4.2 tons) · about 4,167 W at EER 12
Adjust for the room
| Condition | BTU/h |
|---|---|
| Normal room | 50,000 |
| Very sunny (+10%) | 55,000 |
| Shaded (−10%) | 45,000 |
| Kitchen (+4,000) | 54,000 |
| Each extra person over 2 (+600) | +600 |
Rule of thumb: 20 BTU per sq ft with 8 ft ceilings (ENERGY STAR sizing guidance).
Monthly running cost at $0.17/kWh
| Use | Energy | Cost |
|---|---|---|
| 4 h/day | 500 kWh | $85 |
| 8 h/day | 1,000 kWh | $170 |
| 12 h/day | 1,500 kWh | $255 |
FAQ
What size AC for 2,500 square feet?
About 50,000 BTU (4.2 tons); add 10% for a sunny room and 4,000 BTU for a kitchen.
How much does it cost to run a 50,000 BTU AC?
At roughly 4,167 W, 8 hours a day for a month uses 1,000 kWh, about $170 at $0.17/kWh.