Refrigeration Applications: Defrost Load: Hot Subject In a Cold Freezer

The following analysis is offered for the purpose of stimulating discussion from which ARI and ASHRAE committees may establish standard procedures for determining and reporting refrigeration loads arising from defrost.

While coil manufacturers test and publish accurate ratings on their low temperature coils in accord with ASHRAE or ARI standards, few coil manufacturers provide rating information about the heat gain or additional refrigeration loads or loss of refrigerating time arising from their coil defrosts. System designers frequently guess at this portion of the load by calculating the known load based on 24 hours but selecting the equipment based on 18 hours of operation, or some other approximation.

Citation: ASHRAE Journal, vol. 43, no. 2, February 2001



Product Code(s): D-6011