How do you calculate the size of a heat pump system?

To calculate the size of a heat pump system, the correct approach involves dividing the total heating BTUs needed by the efficiency coefficient of the system. This is because the efficiency coefficient, typically expressed as the Coefficient of Performance (COP), indicates how effectively the system converts energy input into heating output.

In practical terms, if you need a certain number of BTUs to sufficiently heat a space, the efficiency of your heat pump will determine how much energy the system actually consumes to produce those BTUs. By dividing the total heating requirements by the efficiency, you can determine the necessary capacity of the heat pump system required to achieve the desired heating effect.

This calculation ensures that the system is neither under-sized, which would lead to inadequate heating, nor over-sized, which could lead to inefficiencies and increased costs. Understanding this relationship between BTUs needed and the efficiency allows for proper design and sizing of HVAC systems.