BTU/hr to Tons Conversion

There are 12,000 BTU/hr in one ton of cooling. Common sizes: 12,000 BTU/hr = 1 ton, 18,000 = 1.5 tons, 24,000 = 2 tons, 36,000 = 3 tons, 48,000 = 4 tons, and 60,000 = 5 tons. A ton of refrigeration is a unit of cooling capacity, and the term originates from the amount of heat required to melt one short ton (2,000 pounds) of ice at 32°F in 24 hours: 2,000 lb multiplied by the latent heat of fusion of ice (144 BTU/lb) divided by 24 hours equals 12,000 BTU/hr. In commercial HVAC, cooling equipment capacity is commonly expressed in tons for larger systems and BTU/hr for smaller equipment. Residential air conditioners typically range from 1.5 to 5 tons (18,000 to 60,000 BTU/hr), while commercial rooftop units range from 3 to 150 tons. Manufacturers may list capacity in either unit depending on the product line, so conversion between the two is a routine step in equipment selection and load calculation review.