Many refrigerated truck drivers have encountered such problems. The refrigerated unit has been working, but the temperature of the cold compartment has not reached the preset temperature. Today we will analyze what should the refrigerated truck temperature fail to drop. .
1. Whether the refrigeration unit is malfunctioning
Whether the refrigerator is working normally, this should be the first confirmation. The refrigerated truck refrigeration unit is mainly composed of four parts: the refrigeration compressor, the condenser, the air cooler (evaporator), and the solenoid valve, plus the oil separator and the liquid storage. It is composed of barrel, sight glass, diaphragm type hand valve back filter and other components. Whether a refrigerated truck can transport the goods in transit to the destination with quality and quantity, in addition to the integrity of the external hardware of the vehicle, the most important thing is whether the refrigeration unit can work normally. Under normal circumstances, the following problems will occur:
Both high pressure and low pressure of refrigerated truck refrigeration unit compressor
Diagnosis method: First, check whether there is frost on the low pressure pipe. If frost is formed, the expansion valve opening is too large. Rinse the condenser with water again. If the effect is obviously better, the cooling effect of the condenser is poor. If nothing changes, there is air in the system. The rest is too much snow. If there are no bubbles in the glass eyes when the air conditioner is turned on or off, it is certain that there is too much refrigerant. As long as some refrigerant is discharged, the fault can be eliminated.
Refrigerator truck refrigeration unit compressor low pressure high, high pressure low
The method is as follows: disassemble the low-pressure pipe of the compressor, and try to block the high-pressure pipe behind the pressure gauge. Start the engine and connect the 12V power supply to the electromagnetic clutch. If the pressure is lower than 15 kg per square centimeter, it is certain that the compressor is broken. Generally, only the compressor assembly is replaced. Please note that during the test, the diagnosis can be confirmed as long as the engine runs for less than half a minute, so do not run for too long.
When the compressor of the refrigeration unit of the refrigerated truck is running, the low pressure is sometimes vacuum, sometimes normal
It can be confirmed that there is water in the system. The only way to do this is to re-evacuate. Generally, you need to replace the receiver dryer and refill the refrigerant.
The low pressure of the compressor of the refrigeration unit of the refrigerated truck always indicates the vacuum
Reason: The system is blocked and the refrigerant does not circulate. The most easily blocked places are generally the expansion valve and the receiver dryer. Just touch the inlet and outlet pipes of the liquid storage dryer. If the temperature is very different, you can be sure that the filter in the liquid storage dryer is clogged, and it is usually a new one.
Refrigeration unit pipeline leak
For fluorine-filled units, this problem is more common, because Freon circulates in a close-closed pipeline, and there is no loss in itself. Then, leakage occurs when freon is added, which requires the use of pressure test and other methods to detect or even repair.
2.How is the insulation effect of the refrigerated box?
After the refrigeration unit is confirmed to be normal, it is necessary to confirm the thermal insulation status of the refrigerated truck and whether there are obvious exposed parts. If this is the case, we should first start to improve the thermal insulation effect of the refrigerated truck compartment.
3.Avoid the goods blocking the cooler evaporator
When loading goods in a refrigerated truck, you need to pay attention not to stack too much goods in front of the evaporator outlet of the refrigerated truck, otherwise it will hinder the circulation of cold air in the car, load too much goods, and blockage above the goods will cause a short circuit of the cold air flow. , So the temperature in the compartment can never drop.
All in all, the internal temperature of the cold compartment cannot reach the preset temperature, which is basically caused by the above reasons. It is recommended that drivers and friends do not load too high or too much when loading goods. At the same time, no matter what goods are loaded, the cold compartment is pre-cooled 1-2 hours in advance, and the cooling effect will be twice the result with half the effort.
Truck chiller unit Model: C300F
For minitruck, pickup, Bakkie, UTE vehicles
from 6-12m3.
Original Top Brand parts, Sanden, QP, TM compressor, Danfoss, etc
Applying for: chiller and freezer truck, pickup, bakkie, UTE vehicles, etc
