A refrigeration system for objects is disclosed. The system includes a refrigeration device and a defrost system. The refrigeration device provides a case or container defining a space for the objects, a first heat exchanger associated with the container for cooling a fluid communicating with the space to cool the objects and a second heat exchanger to receive a heat supply from an air source for warming the fluid. A system for cooling articles is also disclosed. The system includes a space configured to contain the articles, a first element to provide cooling of the articles within the space, a first coolant source to refrigerate the space by cooling the first element in a first state, and a second coolant source to elevate a temperature of the first element in a second state.