Enter the volume of the room, difference in temperature, time in hours, and rate of heat transfer into the calculator to determine the cooling capacity.

Split Unit Formula

The following formula is used to calculate the cooling capacity for a split unit air conditioner.

CC = (V * D * T) / R


  • CC is the cooling capacity (BTU/hr) V is the volume of the room (cubic feet) D is the difference in temperature (Fahrenheit) T is the time in hours (hr) R is the rate of heat transfer (BTU/hr/°F)

To calculate the cooling capacity, multiply the volume of the room by the difference in temperature, then multiply the result by the time in hours. Divide the result by the rate of heat transfer.

What is a Split Unit?

A split unit, also known as a split system or ductless system, is a type of air conditioning system that is split into two parts: an indoor unit and an outdoor unit. The indoor unit, which contains the evaporator, is installed inside the room that needs cooling, while the outdoor unit, which contains the compressor and condenser, is installed outside the building. These two units are connected by a set of electrical wires and tubing. This type of system is often used in situations where window AC units or baseboard heating would be inefficient or impractical.

How to Calculate Split Unit?

The following steps outline how to calculate the Cooling Capacity for a Split Unit.

  1. First, determine the volume of the room (V) in cubic feet.
  2. Next, determine the difference in temperature (D) in Fahrenheit.
  3. Next, determine the time in hours (T).
  4. Finally, determine the rate of heat transfer (R) in BTU/hr/°F.
  5. After gathering all the variables, use the formula CC = (V * D * T) / R to calculate the Cooling Capacity.

Example Problem:

Use the following variables as an example problem to test your knowledge.

Volume of the room (V) = 500 cubic feet

Difference in temperature (D) = 10 degrees Fahrenheit

Time in hours (T) = 8 hours

Rate of heat transfer (R) = 1000 BTU/hr/°F