The Trane XR13 heat pump provides a cooling efficiency rating of up to 14.5 Seasonal Energy Efficiency Ratio (SEER) and a Heating Seasonal Performance Factor (HPSF) of up to 8.5. The ability of heat pumps to handle both heating and cooling tasks makes them popular in warm climates.
There are seven sub-models of the Trane XR13 that range from a low of 17,000 British Thermal Units Per Hour (BTUH) to 58,500 BTUH. Professional installers can determine the proper BTUH based primarily on annual temperature for a particular climate. They recommend going at least one step up in efficiency to reduce the work load on the heat pump.