Principle of automatic defrosting of refrigerators
When the compressor runs to a certain time, the defrost thermostat on the evaporator feels the temperature of -14 degrees after conduction, at this time the defrost timer runs (there are large and small plastic gear cam structures and multiple pairs of electrical contacts), when the compressor works (running) for about 8 hours, the defrost timer just goes to the position where the defrost is turned on, at this time the defrost heater (tube) turns on the defrost heating (heating the frost layer on the evaporator) to start, when the defrost thermostat feels positive 5 degrees when the contact of the defrost thermostat is disconnected, The defrost thermostat (tube) stops working, the defrost timer starts to run for more than 2 minutes, and the compressor circuit is connected to the compressor circuit for the next cycle due to the action of the cam.
