How to Calculate HP for an Air Conditioning Unit
- 1). Multiply the air conditioner's size in tons by 12,000 to convert its cooling capacity to British Thermal Units per hour. If the air conditioner has a 1.5 ton capacity: 1.5 x 12,000 = 18,000 BTUs per hour.
- 2). Divide this answer by 3.412 to convert it to watts: 18,000 / 3.412 = 5,275 watts.
- 3). Divide the wattage by 745.7 to convert it to horsepower: 5,275 / 745.7 = about 7 horsepower.
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