Multi-temperature evaporator refrigerator system with variable speed

Abstract

A refrigeration appliance is provided having at least two refrigeration compartments, each compartment having its own access door. The appliance includes a single evaporator located in a plenum which is selectively in communication with each of the compartments, a single compressor, preferably run by a variable speed motor, and a refrigerant circuit including a series of conduits for providing a flow of refrigerant to the evaporator and compressor. A first restriction device is provided in the conduit connecting the compressor with the evaporator, the restriction device operating at a first pressure level. A second restriction device is also provided in the conduit connecting the compressor with the evaporator, preferably in parallel with the first restriction device, the second restriction device operating at a pressure level higher than the first pressure level. Also, a valve or valves preferably of the latching kind, is positioned in the refrigerant circuit for directing refrigerant to a selected one of the restriction devices, or closing both circuits entirely. A phase change material may be used in the refrigeration circuit, downstream of the restriction devices to improve energy efficiency of the system. Also, with this system, the compartments of the refrigerator appliance can be run either in freezer or in fresh food cooling mode as desired, providing convertible refrigerating compartments.