1. Improper adjustment of the expansion valve and liquid outlet valve of commercial refrigerators, too much refrigerant in the system, air in the refrigeration system, poor sealing of the valve plate assembly, wear of the compressor cylinder sleeve piston, etc.

2. The high-pressure output buffer tube in the compressor is broken, or the screws fixing the tube are loose, causing the high-pressure tube to not exhaust, the low-pressure tube to not inhale, and the compressor to operate without refrigeration.

3. The refrigeration system leaks, the refrigerant is all used up, although the compressor is running, there is no refrigerant in the system to evaporate and absorb heat, so the temperature in the commercial refrigerator does not drop.

4. The capillary is blocked, and the refrigerant cannot enter the evaporator to evaporate and absorb heat, so the temperature in the commercial refrigerator does not drop.

5. The refrigeration system of the commercial refrigerator leaks due to improper welding or use. If the refrigerant in the refrigeration system leaks out within a certain period of time, it will not refrigerate.

6. Check whether the commercial refrigerator is in the correct gear. Different gears have an impact on the power consumption and temperature of the commercial refrigerator.