Why Ac Comes in Ton?

Before electric air conditioners existed, people used large blocks of ice to cool their homes and businesses. The ice absorbed heat and slowly melted as it warmed up. The use of tons to measure cooling capacity comes from this time. A ton refers to the amount of heat it takes to completely melt a ton of ice.

What does ton mean for AC?

In the HVAC field, a ton, or tonnage, refers to the cooling capacity of an air conditioner. Tonnage is measured in BTUs or “British Thermal Units.” (A BTU is equivalent to the amount of energy (heat) needed to raise one pound of water 1°F at sea level.)

What does 3 ton AC unit mean?

' One ton means the rate of heat transfer needed to freeze one ton of water in 24 hours. This is equivalent to 12,000 Btu/hr. So, a 3-ton AC for instance, does not actually weigh 3 tons. It means that it has a nominal capacity of 36,000 Btu/hr.