Failure and Maintenance of Dehumidifier (Ⅱ)

In the use of dehumidifier, there will be a variety of failures. The following describes the common failures of dehumidifier.

Failures 1: After the industrial dehumidifier is started, it will automatically shut down, and it will take a long time to restart, and the dehumidification effect is very poor.

Cause of failure: After inspection, it is found that the wind speed at the air outlet is lower than the normal value. Use a multimeter to measure the resistance value between each outgoing line of the fan motor, and it is found that it is much lower than the normal value. The dehumidifier compressor is a rotary compressor with poor heat-resistant performance. When the fan motor speed is reduced, the air volume is reduced, that is, the air volume flowing through the condenser is reduced, which causes the compressor exhaust pressure to rise, resulting in the compressor overheating protection (shut down). The temperature of the compressor can only be reduced to normal after a long time of cooling, so the compressor can be restarted after a long time.

Maintenance method: According to the inspection, it is judged that the winding coil of the fan motor is short circuited, which causes the fan speed to decrease and the air volume to decrease, resulting in this kind of failure. Replace with a new fan motor to solve the problem.

Failures 2: The commercial dehumidifier operates normally, the relative humidity of the environment is 85% to 90%, but the dehumidifier's dehumidification efficiency is very low.

Cause of failure: Open the air inlet plate of the dehumidifier, let the dehumidifier run, and check the evaporator at the same time. It is found that only a few U-shaped pipes have condensed water, and the surface of other U-shaped pipes is dry. Through further inspection, it is found that there is oil trace at the interface of a pipeline, so the fault is caused by leakage.

Maintenance method: Discharge the refrigerant in the dehumidifier, seal the leakage, vacuum the pipe, and finally inject the refrigerant to eliminate the failure. 

Failures 3: The compressor and fan of home dehumidifier can work normally, but the dehumidification effect is very poor.

Cause of failure: Through inspection, it is found that the air filter screen of the dehumidifier, the surface of the evaporator and the condenser are very clean, and the surface of the pipeline is free of oil leakage. The dehumidification effect becomes normal when the capillary tube and evaporator are wrapped with a hot towel, so the failure is caused by the cooling pipe blocked by ice.

Maintenance method: Clean all the refrigerants with more water content in the dehumidifier, and fill the dehumidifier with nitrogen with a pressure of 0.3MPa to clean its interior, and then vacuum the cooling pipe of the dehumidifier with a vacuum pump. Then add the refrigerant, let the dehumidifier run for 30 minutes, and then stop the machine for vacuumizing. When the vacuum degree meets the requirements, add the refrigerant again to eliminate the failure.

If you have encountered other kinds of machine failure, please feel free to email us for help!