Sensible Heat Factor

In general, geothermal heat pumps are designed to operate with a space sensible heat factor (SHF) of 0.75 to 0.78. SHF is defined as the sensible cooling load divided by the total cooling load.

The heat pump's sensible capacity may be increased somewhat by increasing the air flow or water flow rates.

An SHF of about 0.75 is adequate to handle the latent loads in most parts of the U.S.. The conditions in southern coastal cities are the most severe from this standpoint.

Exercise caution in sizing the heat pump where the SHF of the load does not match the SHF of the heat pump.

Here are the guidelines:

  • The heat pump SHF should be equal to or less than the SHF of the space to be cooled, and
  • The heat pump should be sized based on a sensible cooling capacity within 10 percent of the sensible space load.

In special cases where humidity is a problem, the heat pump should be sized to provide the required latent capacity and external re-heat to avoid overcooling.