A patent for a refrigerant distributor that works as a multi-circuit distributor for ammonia refrigeration evaporator heat exchangers operating with dry or near-dry expansion was awarded to Colmac Coil, Colville, Wash.

According to the company, the invention uses the principles of gravity and phase separation rather than pressure drop to distribute equal amounts of refrigerant liquid and vapor to all circuits. It can be used with any refrigerant at any operating temperature, but is particularly well suited for use with ammonia.

The use of gravity and phase separation and the minimized pressure drop during hot gas defrost are two of the improvements the new patent makes to the safety and reliability of refrigerant distributors.