the common faults of mechanical thermostats | temperature controller
1. The thermostat terminal is stuck and falls off
Cause the compressor to fail to start, the thermostat's moving and static contacts cannot be disconnected, the compressor cannot be operated, the thermostat contacts cannot be disconnected, and the motor of the refrigerator compressor cannot stop running, except for the balance spring press In addition to weak elasticity, it can also be caused by adhesion due to accumulation of words on the contacts. In this case, you can cut off the power supply, turn the thermostat knob from "stop" to the coldest position repeatedly, and then connect the power supply, it will return to normal, indicating that the fault has been eliminated.
2. Compression won’t start due to thermostat open circuit
The main reason for the thermostat disconnection is the disconnection of the wiring to the clip or the leakage of the temperature sensing agent in the temperature sensing bulb. The temperature sensing agent leaks, the pressure in the temperature sensing chamber is reduced to atmospheric pressure, and the lever connected to the moving contact is only subjected to the tension of the balance spring, so the moving and static contacts cannot be closed. The thermostat is in an open circuit state and the compressor cannot be started. For further inspection, hold the temperature sensing tube with your hand and add a cylinder to it slightly. If the contact is still not closed, it means that the temperature sensing agent is indeed leaking.
3. The temperature sensing tube of the thermostat leaves the surface of the evaporator, causing non-stop
The temperature control of the thermostat is too low, causing no hunger. , It should be noted that whether it is a newly installed or repaired thermostat, the refrigerator must be debugged after it is installed to keep the box temperature within the rated range. Under normal circumstances, the temperature of the refrigerating room is 2 degrees. If the thermostat contact is closed when it is higher than 10 degrees Celsius, it needs to be adjusted. During the adjustment operation, first check whether the temperature sensing tube is installed properly.