TABLE OF CONTENTS 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 (non-electric) 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 are not readily available, manufacturers' published data on water coils can be modified to estimate performance of the desuperheating coil.
Most supermarkets rely on central air conditioning and the latent cooling effect of refrigerated cases for moisture removal. Dehumidification through condensation in refrigerated cases is especially inefficient due to the additional energy required for defrost and recooling cycles. If drain-pan and anti-fog heaters are included, the actual energy consumed is typically twice the theoretical...
