Replaced evaporator fan and allowed evaporator coil to defrost. After two days, evaporator coil was frosted over again. Ordered defrost thermostat and heater. Replaced thermostat, check continuity of defroster heater element. Had continuity so did not replace at this time. So far everything working and refrigerator compressor fan does not run constantly thus appears to be going into defrost mode. Keeping defrost heater for a couple more days to be sure evaporator coil does not ice over again. Instructional repair videos related to trouble shooting and parts replacement were extremely helpful and appreciated. Without them, repair would have been much more difficult. Love this site now for all my appliance parts and repair needs.