Unknown element in the refrigerator circuit - help to understand what it is?
Hello. In our family, the refrigerator worked great for a long time, but recently it became necessary to tap the temperature regulator a little when you notice that the temperature in the refrigerator is elevated. If you hit it, the refrigerator will work and everything will return to normal.
In short, I decided to look at this thermostat. And by the way I was interested in a couple of white wires going to the thermostat contacts on the one hand, and on the other hand they are sitting on the evaporator tubes in the refrigerator.
And here is my question: what is it? The temperature regulator is purely mechanical. You can’t pick up any sensors to it. Most likely some kind of actuator is connected. Maybe some kind of valve. This element shows a break in the ring, it is connected to the contacts 3-4 of the temperature controller, and the temperature controller at the time of measurement showed these contacts closed. In general, the question remains what is the function of this element and how it implements it.
I am enclosing a photo of the connection point of two white wires to the evaporator. And this connection point - what is it? How does it work?
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Good evening. Unfortunately, you provided too little information and a low-quality photograph. But what you described is very similar to ten defrost. At least I recall a similar design in the Soviet Biryus 6 model. It was repeatedly modernized there, and now, in my opinion, they are not released at all. Also, modern refrigerators of the “know frost” type have such an arrangement.
Ten can be electronic or mechanical. The technical principle of its operation is approximately as follows:
1. Connect the refrigerator to the mains.
2. The contacts on the thermostat 3 and 4 are in the closed state.
3. Thawing is carried out when a certain minus temperature is reached, usually −10 degrees.
4. A special defrost timer under these conditions disables the evaporator blower fan and the running compressor, while supplying voltage to the evaporator heater.
5. When the temperature rises to +10 degrees, the defrost timer opens the contact on the heating element and closes again on the compressor, for cooling.
The defrost heater is located on the evaporator body (the modification varies depending on the model).And the very detail that you talked about is the defrost sensor.
Judging by the symptoms, something happened to the thermostat relay. For some reason, he does not want to close the defrost / freeze modes, and when you hit him, the contacts close. It would be interesting to find out the model of the refrigerator, get another photo and more about how when you beat it and it starts up, it works in normal mode or freezes or vice versa, it produces a temperature higher than normal and so on. To begin with, it will not be superfluous to disassemble everything carefully and check all connections, try to restart them.