Here we make 7 possible reasons that case your parking air conditioner evaporator freezing (not cooling). After it, you may have a clear mind on how to use truck air conditioner efficiently.  
 

 

Causes and Treatment Methods of Evaporator Freezing of Parking Air Conditioner

 

1. Low refrigerant content in truck air conditioner

The refrigerant is insufficient, and the semi truck air conditioner will leak or leak due to reasons such as installation or long-term use.

After the refrigerant in the refrigeration system is reduced, the evaporation pressure is too low, which leads to the freezing of the evaporator, and the position of the freezing is generally in the front part of the evaporator.

Remedy: deal with the leaking part first, add enough refrigerant, and the fault will be eliminated.


 

2. Compressor compression efficiency is reduced

The parking truck air conditioner compressor efficiency is low, the compressor failure has been used for a long time, the compression efficiency of the compressor is reduced, or the compressor air distribution system is damaged, causing the pressure to be too low and freezing.

Remedy: The icing position is also in the front part of the evaporator. The former is supplemented with some refrigerant, and the fault can be eliminated. If the fault persists, the compressor must be replaced.


 

3. Too much refrigerant in truck air conditioner

There is too much refrigerant, and some parking air conditioners are re-injected with refrigerant due to displacement, leakage and other reasons. The maintenance personnel added too much refrigerant due to improper operation, which caused the excessive refrigerant to flow to the evaporator and partially evaporate and freeze. This type of ice is often found in the rear part of the evaporator and around the return pipe of the compressor.
Solution: Drain the excess refrigerant and the fault will be eliminated.


 

4. The surface of the evaporator is dirty due to prolonged use

Dirty heat exchanger and dirty evaporator After the parking air conditioner is used for a period of time, the dust in the air or the microorganisms produced by the evaporator will accumulate on the evaporator, hindering the air circulation, resulting in reduced heat exchange, and the evaporator temperature is too low and it freezes.

Remedy: In this case, the icing position is in the rear part of the evaporator. After the ice has melted, rinse the evaporator with water, and brush along the fins with a soft brush, being careful not to get the electrical parts wet. After cleaning, the fault is eliminated.


 

5. The parking air conditioner temperature is set too low

The temperature setting of parking truck air conditioner is too low, the temperature setting of the air conditioner is too low, the cooling capacity of the air conditioner cannot keep up, the room temperature cannot drop below the set temperature, and the machine is turned on for a long time, or the shutdown time is very short, which will also cause the evaporator to freeze. Some rooms have a very low temperature, which can also cause the evaporator to freeze.


 

6. Poor contact of the thermostat

The temperature probe is not good or the temperature probe is installed in an improper position, and the temperature control fails. The gas pressure of the temperature sensor of the mechanical thermostat changes with the temperature change, which drives the contact action of the thermostat. Due to contact adhesion, insufficient spring elasticity, etc., the contacts are normally closed, and the air conditioner is continuously turned on, resulting in icing.
Solution: replace with a new thermostat and troubleshoot.


 

7. There is dirt on the fan blades, resulting in low air volume

The air volume of the internal unit is small, and the air volume is small. After the parking air conditioner is used for a period of time, some fan blades are stuck with a lot of scale, which affects the air supply and causes the evaporator to freeze. Remove scale, troubleshoot.