Service technicians often confuse motor horsepower (hp) with tons of refrigeration. One common misconception is that 1 ton of refrigeration equals 1 hp. This statement is only true in some of the higher-temperature applications, such as air conditioning. In medium- and low-temperature refrigeration applications, 1 hp is hardly ever equal to 1 ton of refrigeration. Let’s review a few principles to illustrate this point.
First, a ton of refrigeration is a rate of heat transfer, not an amount. One ton is equal to the heat absorbed in melting 2,000 pounds (1 ton) of ice at 32°F in 24 hours (one day). This equates to 12,000 Btuh.