Refrigeration Cycle: Pumped Overfeed Refrigeration System

A “pumped overfeed” or “recirc system” is similar to the gravity-flooded system in that it utilizes a vessel that was not part of the DX system. In a pumped overfeed system, however, the vessel, often called a “recirculator”, is not located above the evaporator. In fact, the recirculator may be a long distance from the evaporator. Instead of using gravity to supply liquid to the evaporator, the recirculator will have a pump connected to the bottom of the vessel, which will move the cold liquid refrigerant from the recirculator to the evaporator.As with the DX and flooded systems, the liquid will boil inside the evaporator. Vapor formed in the evaporator is returned to the recirculator, where it is separated from the liquid and rises to the top of the vessel.

The vapor from the recirculator is piped to the suction inlet of the compressor.