To defrost a selected evaporator, in a system including at least two evaporators, the system condenser is isolated from the compressor and the selected evaporator receives hot, compressed refrigerant vapor directly from the compressor. The liquid refrigerant formed in the defrosting evaporator flows...http://www.google.de/patents/US4122686?utm_source=gb-gplus-sharePatent US4122686 - Method and apparatus for defrosting a refrigeration system
