The dynamics of the refrigeration/defrost cycle has been examined for different test fan-coil unit (FCU-T) entering air dry-bulb temperatures (EAT). This paper (Part IV) provides a detailed description of the time-dependent history of refrigerant temperatures and pressures and air temperatures for cases where the entering air dry-bulb temperatures are -8°F and -13°F. The intent of this paper is to provide insight into the behavior of a refrigeration system during the complete refrigeration/defrost cycle using the hot-gas refrigerant defrost method.

Units: I-P