Abstract: A refrigeration system for merchandisers, drug cabinets and similar enclosures (10) that continues to provide temperature control during periods when external power is not necessarily available. The system typically has a compressor/condenser subsystem (11) that is powered by mains electricity (16) and a second subsystem (12) that includes an insulated eutectic tank. The compressor/condensor (11) cools the tank (12) using external electrical power, when available, while the tank cools the enclosure (10) without requiring external power. A refrigerant loop (14) between the second subsystem (12) and the enclosure (10) operates by way of convection and/or gravity and a simple controller (15).