So, it’s time to throw your old broken refrigerator into the landfill? Even if it is no longer repairable (for example, due to a freon leak), there are still valuable working units and spare parts on it that need to be removed! First of all, this concerns the compressor of the refrigerator. It will come in handy more than once for pumping air, for example, in wheels or for making a home-made paint sprayer — 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 muffled tightly. The copper tube in the immediate vicinity of the unit can simply be eaten with wire cutters, and not sawn off. Of course, before proceeding with dismantling, the refrigerator must be unplugged!
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, a hissing sound is clearly audible — air is sucked into one tube and thrown out into another. Remove the assembly from the old refrigerator as carefully as possible so that the oil in it remains safe and sound. 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.
Having determined the outlet pipe from the compressor, it is better to mark it immediately, 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 connect the relay correctly, you need to study the refrigerator diagram 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 are not preserved, the circuit diagram can be found on the Internet.
Also, the new device will have to be equipped with a receiver, which can be bought in a store or made independently. You will also need a plastic bottle for assembly, through the holes in the lid of which the inlet and outlet tubes will pass. After inserting the tubes, the bottle should be filled with epoxy resin, and the bottle should stand with the cap down until the resin hardens. After the resin hardens, the tubes and the cap will be tightly mounted into the bottle.
To connect the air pumping unit to some kind of device, you will need windshield washer hoses, which, like a relay, can be bought at any car 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 the old refrigerator should not work longer than 45 minutes.See also - The refrigerator freezes food: why is this happening?
How to check the wiring and connect the compressor from an old refrigerator without a relay and a circuit?
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 here, but 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 mistakenly claim that the working winding is the one that shows more resistance. But this is fundamentally not true.
The working winding is the one that shows the least resistance! And the one that shows more resistance is the starting (starting) one! If you mix them up and connect the compressor incorrectly, it will quickly overheat and will not last long at all. Therefore, in this case, accuracy is needed!
This is the rule that works for refrigerator compressors, and this should not be forgotten. The next obligatory preparatory stage before connecting is to check if any of the windings breaks into the case. Otherwise, it may happen that you touch the body of a working device, and you will be shocked. And this is not excluded, because the compressor is not new. To check, you need to touch the winding output with the left terminal, and with the right terminal anywhere on the body, test the second and third outputs in the same way. Only if the device has shown that all three outputs are reliable and do not break through, can such a compressor be connected to a working 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 applied by briefly touching 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 more can not be allowed.See also - Is freon from the refrigerator harmful to humans?
If the wiring is in order, you need to change the oil!
Of course, you can leave the old oil, but is it worth it to spend 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 fill in 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 the new oil is poured.
How to extend the life of the compressor?
Prevention of overheating and premature failure of the compressor is a sufficient amount of oil, proper connection to electrical outlets and time limits. It is not bad to connect a capacitor between the common and starting outputs, especially if it was in the refrigerator. This simple device increases the efficiency of the engine and extends its service life.