Supermarkets present unique air-conditioning requirements. Due to the cooling effect of refrigerated display cases, the, primary requirement is moisture removal. The use of a desiccant dehumidifier is justified over standard vapor-compression equipment whenever inexpensive (nonelectric) energy is available for regeneration. The cost effectiveness can be further enhanced with the utilization of condenser heat from freezer and case systems to, preheat regeneration air. A desuperheating coil is required to recover the high-grade energy needed for reactivation. Since performance data on desuperheating coils for R-502 is not readily available, manufacturers' published data on water coils can be modified to estimate performance of the desuperheating coil.