What are the troubleshooting steps for a refrigerated truck not cooling?

[MacIris]

Common causes of refrigeration unit failure in refrigerated trucks are analyzed as follows: Refrigeration unit pipeline leakage: For units that use Freon, this issue is relatively common. Since Freon circulates in a nearly sealed pipeline, there should be no natural loss. If leakage occurs during Freon charging, methods such as pressure testing should be used for detection or immediate repair. Refrigeration unit compressor failure: Overheating of the refrigeration unit compressor can cause the protector to fail. If the unit itself is functioning properly, the issue likely lies with the compressor. Refrigeration unit pipeline blockage: Blockages can occur due to incomplete vacuum extraction or moisture leading to ice blockage.

[MacCollin]

A refrigerated truck not cooling is indeed a headache. I've dealt with many similar cases before. The most common issue is refrigerant leakage or insufficient levels – just like a car can't run without fuel, you need to check if there are any pipeline damages. If the compressor's belt is loose or broken, the entire system will fail, so listening for abnormal noises during startup is crucial. When the condenser gets clogged with mud splashed from the road, heat dissipation becomes impossible, especially in summer when it's prone to overheating and shutting down. Power issues shouldn't be overlooked either – problems like low battery voltage or generator failure can cause the refrigeration system to stop working. Aged door seals leaking cold air can also prevent temperature drop – I've seen this several times, and replacing the seal usually solves it. Circuit board malfunctions are more troublesome; I recommend using professional equipment to check circuit continuity. Always test the refrigeration function before loading cargo – don't wait until you're on the road to discover problems.

[JasperLynn]

I've been driving refrigerated trucks for over a decade. When encountering cooling issues, I always check routine maintenance first. Insufficient refrigerant is the most common problem, especially in older vehicles where pipelines are prone to leaks. Before departure, always check if the pressure gauge readings are normal. Compressor belt wear is another major issue - once on the highway, my entire cargo compartment temperature soared due to a broken belt. A dirty condenser reduces efficiency, so I wash the radiator fins with a water gun every week. If the compartment temperature won't drop, it might be due to damaged insulation, especially at the seams of aged refrigerated truck bodies where hot air can seep in. Electrical failures are also frequent, such as blown fuses or poor relay contact. I recommend regularly replacing filters and dryer bottles, as these small components affect the entire system's operation. Develop the habit of recording refrigeration data on shipping documents for easier fault tracking.

[RubyMarie]

When a refrigerated truck's cooling system fails, troubleshooting should start with key components. Issues in the refrigeration cycle often originate from the compressor - seized bearings or burnt-out coils can cause it to stop working. If the condenser fan isn't rotating, it leads to high-pressure overheating, which can be diagnosed by feeling the pipeline temperature. Excessive frost buildup on the evaporator hinders heat exchange, often caused by malfunctioning defrosting devices. Control system failures are more subtle - for instance, faulty temperature sensors may provide incorrect readings. Power supply voltage fluctuations or aging batteries are frequently overlooked; using a multimeter to measure startup voltage can reveal these issues. Be cautious of pipeline blockages - stuck expansion valves or saturated dryer bottles can obstruct refrigerant flow. Frequent door openings or poor sealing also compromise the insulated environment. Only by systematically checking each component can the problem be fully resolved.