Compressor is the heart of the refrigeration system. Whether it is air conditioning, cold storage, chemical refrigeration process, etc., there must be an important part of the compressor to protect! There are many types and forms of refrigeration compressors. According to the principle, there are two types of volumetric compressors: volumetric type and speed type. Volumetric type is the most common type.

1. The motor of the compressor is damaged:

First, the wiring of the compressor terminal is incorrect and the motor is burned. Second, the system refrigerant leaks; because the high pressure gas of the rotary compressor is discharged from the compressor, it is also responsible for taking away the heat generated by the motor. If the system refrigerant leaks, only a small amount of high-pressure gas will be discharged from the compressor, so that the heat generated by the compressor motor in the energized state will always accumulate. In the long run, the compressor motor will burn out. When the compressor is blocked, the motor factor should be excluded as much as possible. Therefore, first measure the insulation resistance of the motor and the windings of the primary and secondary coils to determine whether the motor is burnt.

2, compressor capacitor problem:

First, the capacitor is damaged (short circuit, open circuit); second, the capacitor specifications do not match the compressor. This item only applies to single-phase compressors. Since a three-phase induction motor is used in a three-phase compressor, since a three-phase alternating current is supplied to the stator core to generate a rotating magnetic field, a capacitor is not required.

3. The thermal protection of the compressor is frequently operated;

First, the thermal protector is not normal; you can consult the performance chart and text description of this specification provided by the compressor manufacturer.

Second, the power line wiring is unreasonable (the wiring of the compressor terminal is not correct, or the inverter of the inverter air conditioner runs out of phase: that is, check the current between the three phases to see if there is a short circuit or open circuit), and the low voltage starts.

Third, the system high and low voltage is not balanced to start; generally requires the air conditioner to be turned on at least 3 minutes after shutdown; it is also possible that the capillary flow of the system is too small and the high and low pressure cannot be balanced as soon as possible.

Fourth, liquid return caused by liquid return, long-term shutdown start, low ambient temperature start, etc.; in the long-term shutdown state and low temperature, the refrigerant in the compressor is dissolved in the refrigeration oil to make the liquid surface (liquid refrigerant) The mixture with the lubricating oil is raised. At the time of starting, the liquid refrigerant in the closed casing evaporates from the dissolved lubricating oil, causing a strong foaming phenomenon. Especially when the ambient temperature is extremely low, the foaming phenomenon is particularly serious, causing the liquid surface to drop sharply. If it falls below the oil level of the pump, the oil will be cut off, the pump body will bite and block, and the current will rise sharply. , the thermal protector action.

4. The copper plating phenomenon or rust of the compressor occurs, that is, the system enters the water: the refrigeration system has strict requirements on water, and the water content in the refrigeration system is generally specified to be less than 0.2 ml. If moisture invades the compressor, it will cause serious damage to the compressor as follows:

First: The mechanical parts of the compressor are copper and rusted. When the copper plating and rusting reach a certain level, the matching clearance between the mechanical parts of the compressor will be reduced, and in severe cases, the compressor may be blocked.

Second, the motor coil paint film, insulation material, etc. are corroded, causing the motor to be short-circuited;

Third, the deterioration of refrigerant and refrigeration oil.

Fourth, the leaf spring is embrittled and broken.

In general, the intrusion of moisture may be caused by incomplete vacuuming or leakage of refrigerant on the low pressure side of the system.

5, the compressor is abnormally worn
First, the clearance of the internal components of the compressor is small, which is generally a problem of the compressor itself.
Second, the problem of frozen oil:

A: bad oil return hole
B: The oil is not enough, or the oil leaks with the refrigerant.
C: Oil metamorphism This is generally because the frozen oil is overheated and charred after the system refrigerant leaks, so that the mechanical part of the compressor cannot be effectively lubricated, and in severe cases, the compressor can be blocked.

D: The system returns poor oil. The refrigeration oil plays a lubricating role inside the compressor, which can effectively prevent the wear of the mechanical parts of the pump body. The oil seal can maintain the pressure difference between high and low pressure, avoid high and low pressure gas, and prevent the cooling capacity. decline. In addition, due to the continuous circulation of the frozen oil, the heat generated between the friction surfaces can be taken away in time. When the amount of refrigerant oil is insufficient, the mechanical parts inside the compressor may be abnormally damaged due to the inability to obtain timely lubrication, and eventually the compressor is blocked.

There are several reasons for poor system oil return:

(1) The length and drop of the indoor and outdoor connecting pipes exceed the specified value; generally, the indoor and outdoor connecting pipes shall not exceed 15m, and the maximum difference is 5m.

(2) The capillary blockage or unreasonable selection of the system and the uneven distribution of the indoor heat exchanger cause the refrigerant to return to the compressor without complete evaporation. The flow rate is relatively slow because it does not completely evaporate. The wall of the heat exchanger causes poor liquid return, which affects the system's ability to improve and fluctuate back and forth.

(3) The system refrigerant leakage brought away the frozen oil, and the refilling of the refrigerant did not supplement the refrigeration oil, resulting in poor system oil return.

6. The compressor has foreign matter entering: the impurities contained in the compressor itself and the impurities brought in the air conditioner system.