Systematic troubleshooting using a system checklist is the best method for the conscientious technician to pinpoint hard-to-find system problems. This article explores how evaporators can become oil-logged. Included are the symptoms of the problem, along with examples of a system with an oil-logged evaporator.
The system in question is a low-temperature refrigeration system using R-134a. It has a thermostatic expansion valve (TXV) for the metering device and a receiver at the condenser outlet.