Refrigerant migration deals with refrigerant migrating back to the compressor’s crankcase during the off cycle. This migration of refrigerant is due to a pressure difference between the compressor’s crankcase and the refrigerant. Refrigerant migration can cause the compressor’s crankcase to lose its oil, thus circulating the oil throughout the refrigeration system. This oil in circulation usually gets caught in the evaporator and can cause an oil-logged evaporator.
Refrigerant flooding refers to liquid refrigerant entering the compressor’s crankcase during the on cycle. Flooding can cause flashing of the oil in the compressor’s crankcase because of the liquid refrigerant boiling under the oil. This phenomenon can also cause the compressor to lose its oil and circulate it throughout the refrigeration system. Excessive oil in the system will again get caught in the evaporator and cause an oil logged evaporator. This article will explore the problems associated with an oil-logged evaporator and a compressor’s crankcase low on oil.