So, it's time to dump your old broken refrigerator in a landfill? Even if it can no longer be repaired (for example, due to a freon leak), there are still valuable working units and spare parts on it that must be removed! This primarily concerns the refrigerator compressor. It will come in handy more than once for pumping air, for example, in wheels or for making a homemade painting machine - an airbrush. To remove the compressor from the refrigerator, you will have to unscrew only 4 nuts and cut off only 2 tubes with a hacksaw - inlet and outlet. The third tube (freon) is jammed tightly. The copper pipe in the immediate vicinity of the unit can be simply bite into with wire cutters, and not sawed off. Of course, before proceeding with dismantling, the refrigerator must be disconnected from the outlet!
The next step is to check the removed unit for operability. To do this, it must be connected to the electrical network. If the compressor is running, the hissing sound is distinctly audible - air is sucked into one tube and thrown into another. You should remove the assembly from the old refrigerator as carefully as possible so that the oil in it remains intact. You need to cut the cable going to the temperature sensor, then you need to measure the resistance and study the location of the closed contacts that will be used during further assembly, it is very good if the circuit diagram of the old refrigerator is preserved.
Preparatory work
Having identified the outlet pipe from the compressor, it is best to mark it right away, because an oil filter will need to be attached to it. In order for the used compressor in the new device not to overheat and fail prematurely, it is better to install a new relay to it, ideally if the relay is original, corresponding to the brand of the old refrigerator. To correctly connect the relay, you need to study the refrigerator circuit and make the connection in exactly the same order that was in the refrigerator and which the diagram shows. If the documents for the refrigerator have not been preserved, the schematic diagram can be found on the Internet.
Also, the new device will have to be equipped with a receiver, which you can buy in a store or make yourself. For assembly, you will also need a plastic bottle, through the holes in the lid of which the inlet and outlet tubes will pass. After inserting the tubes, the bottle should be poured with epoxy resin, and the bottle should stand with the lid down until the resin hardens. Once the resin hardens, the tubes and cap will be firmly embedded in the bottle.
To connect the air-pumping unit to some device, you will need windscreen washer hoses, which, like a relay, can be bought at any auto shop. During operation of the device, you should carefully monitor the oil level, which prevents overheating. It should also be remembered that the compressor from an old refrigerator should not run longer than 45 minutes.
See also - The refrigerator freezes food: why is this happening?
How to check the wiring and connect a compressor from an old refrigerator without relays and circuits?
Many people are interested in connecting a compressor without a relay, and there are significant nuances here, information about which is quite difficult to find. It is not so much the scheme that is important as the principle. First you need to ring the general conclusion, which is located apart, to the left of the other two. Having attached the terminal to the common terminal, you need to find the working winding with the second terminal. For example, one output shows 14 ohms and the other shows 37.9 ohms. Which of these windings is working? Many people mistakenly claim that the working winding is the one that shows the highest resistance. But this is fundamentally wrong.
Important:
The working winding is the one that shows less resistance! And the one that shows more resistance is the starting (starting)! If you mix them up and connect the compressor incorrectly, it will quickly overheat and will not last long. Therefore, in this case, accuracy is needed!
This is the rule that works for refrigerator compressors, and we must not forget about it. The next mandatory preparatory stage before connecting is to check whether any of the windings breaks through to the case. Otherwise, it may happen that you touch the body of the working device, and you will be electrocuted. And this is possible, because the compressor is not new. To check, you need to touch the left terminal to the output of the winding, and with the right - anywhere to the case, in the same way test the second and third outputs. Only if the device has shown that all three outputs are reliable and do not puncture, it is possible to connect such a compressor to the operating device.
The next step is to connect the compressor from the old refrigeration equipment to voltage using the terminal blocks. First - to the common wire and to the worker. And the starting voltage will be supplied by a short touch of the bare wire. But this must be done carefully and carefully so as not to get an electric shock. When voltage is applied, the compressor starts to hum, and when we touch the start output, it turns on and starts blowing air. The optimal operating time is 10-15 minutes, during this time some heating of the unit body is allowed, up to 50 degrees, but it cannot be allowed anymore.
See also - Is freon from the refrigerator harmful to humans
If the wiring is ok, you need to change the oil!
Of course, you can leave the old oil as well, but is it worth spending so much effort to connect the old compressor to the new device for only a few sessions? Most likely, there is long-used oil inside, which contains metal particles and does not protect the unit from overheating well. It is best to completely drain the old oil and refill with new engine oil. Where to fill it is not a question. As a rule, a large bolt is clearly visible on the compressor housing, which must be unscrewed with a wrench. Through the open hole, the old oil is drained and new oil is filled.
How to extend compressor life?
Prevention of overheating and premature compressor failure is a sufficient amount of oil, correct connection to the electrical outputs and time limitation. It's nice to connect a capacitor between the common and the starting outputs, especially if it was in the refrigerator. This simple device increases engine efficiency and extends its service life.
See also:
Good afternoon. Doesn't the compressor need a condenser to start the compressor?
Most often needed, you are right.