The energy and cost efficiency of gas fired engine-driven heat pumps for residences was computer simulated and the influences of the major factors affecting the efficiency were studied by analyzing the operation of various system configurations.

The heat pump model developed previously was expanded for cooling mode and annual performance analysis. Incorporated into the model were the influences of cycling and infiltration on sensible and latent capacity and indoor relative humidity.

This work was part of a Gas Research Institute sponsored study on performance analysis of space conditioning systems.