Precautions for Daily Use of Refrigerated Truck Refrigeration Units

Many people are not very clear about the use of truck refrigeration unit (TRU), and some wrong use methods may reduce the service life of the refrigerating unit. Share several precautions when using TRU:

1. First, let's take a look at the principle of refrigeration units. At present, refrigeration units of refrigerated trucks mostly use mechanical refrigeration, which is basically the same as air-conditioning refrigerators and other refrigeration principles. It absorbs heat at one point and then dissipates heat at another point. The refrigerant absorbs heat through a coil (evaporator) in the cargo space, and then dissipates the heat through another coil (condenser) on the outside. A refrigeration compressorallows the refrigerant to circulate in the system.

1. Understand the components of refrigerated truck refrigeration unit: refrigerant and four major parts, namely compressor, condenser, expansion valve, and evaporator.

Æ Compressor: The compressor is the power of the refrigeration cycle. It is driven by the engine to continuously rotate. In addition to pumping out the vapor in the evaporator in time to maintain low temperature and low pressure, it also increases the pressure and temperature of the refrigerant vapor through compression to create The condition that the heat of the refrigerant vapor is transferred to the external environment medium.

Æ Condenser. The condenser is a heat exchange device that uses the ambient cooling medium (air or water) to take away the heat of the high-temperature and high-pressure refrigerant vapor from the cold compressor to cool and condense the high-temperature and high-pressure refrigerant.

Æ Throttle element (ie expansion valve), high-pressure and normal temperature refrigerant liquid is directly sent to the low-temperature scale evaporator without ears. According to the principle of saturation pressure and saturation temperature-the corresponding principle, the pressure of the refrigerant liquid is reduced, thereby reducing the refrigerant liquid temperature.

Æ The evaporator, the evaporator is also a heat exchange device. After throttling, the low-temperature and low-pressure refrigerant liquid evaporates (boils) into vapor, absorbs the heat of the material to be cooled, reduces the temperature of the material, and achieves the purpose of freezing and refrigerating food. In the air conditioner, the surrounding air is cooled to achieve the effect of cooling and dehumidifying the air.

1. Refrigerators are composed of non-independent and independent refrigerators. Most of the non-independent refrigerators are used. The compressor is the power source of the vehicle engine. Therefore, when using the refrigeration unit, the engine must be started first. When using in winter, the engine should be warmed up for 3-5 minutes before starting the refrigeration unit. For when refrigeration units are often not used. Especially in winter, the refrigeration unit of refrigerated trucks is not often used. The transport refrigeration unitshould be turned on regularly 1-2 times a week and run for about 10 minutes to maintain the normal operation of the refrigeration unit to avoid sinking of the compressor lubricating oil and insufficient lubrication of the components.

1. Regularly check the tightness of the compressor belt of the refrigerated truck. If the compressor belt is too loose, it will cause the compressor clutch to slip and the belt will squeak, slow down the compressor's working frequency, and weaken the cooling effect. There is a tension pulley on the compressor belt, which can be adjusted appropriately. The compressor belt can be adjusted by tightening a tension pulley with a wrench to remove the fault.

1. Understand the working principle of the refrigeration unit, and specifically let the refrigerated truck refrigeration unit cool down quickly:

ÆThe engine speed is not less than 1500 rpm to ensure the rapid and efficient operation of the compressor of the refrigeration unit.

ÆWhen the refrigerated truck is running, ensure good heat dissipation from the condenser of the refrigerating unit. (Regularly clean up debris on the condenser)

ÆThe effect of heating the goods inside the box is obvious. Because the air humidity is relatively high, the temperature of the empty box is slow.

ÆEnsure that there is no shortage of refrigerant in refrigerated trucks, and generally no fluorine leakage occurs, and refrigerant does not need to be added.

6, in addition, pay attention to the following points when using refrigerated trucks:

Æ At high speed, the chiller cannot be started, only at low speed. When stopping, stop the refrigeration unit first.

Æ Do not start the refrigeration unit for a long time when the engine is at idle speed or when the engine is at low speed to avoid battery loss.

Æ When driving at a low speed, do not start the truck freezer unit for a long time to avoid battery loss.

Æ If it is a newly purchased refrigerated truck, the compressor belt of the refrigerator must be tightened after one week of use. Refrigerator truck unit belt is normal. It is normal that a pressure difference of 5 mm appears when a finger is pressed hard. If the belt is too tight, the horsepower of the engine will be lost. If the belt is too loose, the belt will slip and wear out.