the compressor is installed in the outdoor air conditioning unit

Figure 1: The central AC Compressor is in the outdoor unit.

The compressor is the heart of the central air conditioner. It is located in the outdoor air conditioning unit. What if the compressor has faults? This article will help you maintain your refrigeration compressor by four methods. Let’s start it.

Knocking on the Compressor with a Mallet

After tilting the air conditioner for 45 degrees all around, then start it. Knock on the lower half of the compressor with a mallet so that the internal components of the compressor are subjected to vibration and run. The new equipment occurs common faults that the compressor does not start due to being put in place for a long time, keeping the piston rod stationary. In addition, the viscosity of the freezing oil is thicker in winter. For the two reasons, using the mallet to knock on the compressor helps to troubleshoot the faults.

Impacted under Standard Atmosphere

First, the working voltage of the power socket is normal. Then, remove the outdoor air conditioner shell, we could find that the capacitor battery is excellent at charging, and the temperature and current protection devices are normal. Besides, the compressor winding resistance is equivalent to that of the common terminal. So we choose to impact the device under standard atmosphere.

maintain the refrigeration compressor

Figure 2: The maintenance worker is repairing the air conditioner compressor.

This method is needed to discharge the refrigerant first, and then weld the high- and low-pressure pipes with gas. Next, you should weld a copper pipe with a length of 1.5 meters and a diameter of 10mm on the high-pressure pipe of the compressor. In addition, connect one end with the inlet and outlet of the nitrogen bottle to relieve pressure by the hose nozzle. Using the nitrogen to the compressor parts with a 0.1Mpa recoil force, the shaft holding parts have a certain looseness.

The low-pressure breathing outlet exhausts for 5 minutes, then hard start the compressor. As a result, the compressor can easily start to run. Then measuring the current is 4.3 A, re-weld the high- and low-pressure pipes. At last, you should apply the pressure, detect the leakage, pump it and add the refrigerant.

Pressure Relief

The measurement of the compressor winding resistance is normal. After applying the above methods, the compressor is still not able to operate. Finally, we release the refrigerant from the low-pressure gas hose nozzle of the outdoor unit and then knock on the lower half of the air conditioner compressor with a water hammer when starting it. In consequence, the AC compressor runs rapidly.

At this time, you should add 200mL of frozen oil to the low-pressure inlet. After the normal operation of the AC compressor, please put the low-pressure gas hose nozzle and the low-pressure liquid hose nozzle back. Then apply pressure, detect the leakage, pump it and add fluorine.

adding refrigerant to the air conditioner compressor

Figure 3: The maintenance man is adding fluorine to the compressor.

Unusual Start

Use a 220V10A power plug, and three power transmission lines whose length is 1.5 meters, cross-section surface is 1.5 cubic millimeter to make a special tool for opening. Then connect power plug N terminal to the public terminal C of the compressor, terminal L to the bipolar line. Connect a transmission line to terminal M, and another line is hanging in the air.

Once the compressor is powered, use the hanging line to touch the starting terminal S of the refrigeration compressor, and the compressor will start. After the compressor starts, keep in mind that quickly remove the line. If you want to interrupt the operation of the compressor, you should pull out the power plug first, and then take out the wire and connect the compressor wire. Finally, debug the air conditioner.

samsung refrigeration compressormsv488a-l1r 115-127vac 60hz 91w

Figure 4: Samsung Compressor MSV488A-L1R


We suggest you maintain your compressor by four methods, including knocking on the compressor with a mallet, impacting it under a standard atmosphere, relieve the pressure, and start it in some ways if necessary. Wish these methods would be helpful.

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