Causes and solutions of icing at the air outlet of refrigerated truck refrigerator
Everyone knows that the working principle of the refrigerator in a refrigerated truck is similar to that of an air conditioner. Water will be discharged when the cold and heat are exchanged. However, when the refrigerator is working, there is no water flowing out of the water pipe, and the air outlet of the refrigerator is also frozen and blocked. The internal temperature cannot be lowered. What is the reason? How to solve it?
Phenomenon 1: No water is discharged from the drain pipe
No water discharge means that cold and heat cannot be exchanged, mainly for the following reasons:
1. The drain pipe and filter screen are blocked, and the drain pipe is damaged and the condensed water cannot be discharged;
2. Without refrigerant, it cannot be condensed into water;
3. The compressor does not work.
Solution:
1. When the drain pipe is damaged, first check whether there is water dripping inside the box. If it is, the drain pipe is damaged and the drain pipe needs to be replaced in time. If not, check whether the drain pipe and filter light are blocked. You can connect the drain pipe. Open and rinse with water several times to see if it can be dredged. If not, use a thin iron wire to dredge slowly, take out the blockage, and rinse with water until the drainage is unblocked.
2. When the refrigerant is insufficient, the evaporation pressure is low, the evaporator is frosted, and the temperature is slowed down. The liquid in the sight glass is in an intermittent flow state, mainly because the suction pressure is low. Check whether the suction valve is damaged. Add an exhaust valve at a high place to exhaust or increase the flow of cooling water.
3. The compressor is the main engine of the refrigerator. When the compressor is not working, the high-temperature and high-pressure gas inside the cargo box cannot be discharged to the condenser, and the gas cannot be liquefied and discharged.
Phenomenon 2: The air outlet of the refrigerator is frozen and blocked
what is the root cause?
1. The contents of the cargo box are stacked too high, and the flow of cold air inside the cargo box is blocked, causing the air outlet to be too cold and freezing.
2. The refrigerator does not have the defrost function, and the air outlet will be frosted if the air outlet is blown for a long time. If the refrigerator unit does not have the defrost function, the air outlet will freeze.
3. The dragged items have high moisture, and long-time blowing will cause the moisture content of the air inside the cargo box to be large, causing the air outlet to freeze.
4. The speed of the cold air motor of the evaporator is not enough, and the wind is weakened and the air volume is too small.
Solution:
1. When loading, do not stack the cargo too high. If the air outlet is blocked by the cargo or too close to the cargo, the cold air will gather near the air outlet and flow like the law, causing the air outlet to freeze and block, and the air-conditioning cannot be normally in the compartment Internal circulation, which increases the local temperature of the goods and affects the refrigeration effect.
2. The refrigerator does not have an automatic defrost function. When choosing a refrigerator, it is best to choose a refrigerator unit with automatic defrost function. Otherwise, you need to manually clear the frost at intervals to prevent the air outlet from freezing.
3. The loaded items have high moisture content, and the goods are not packaged in place, which makes the air humidity inside the cargo box high, and the air outlet location is easy to freeze. The solution is to keep the pulled items airtight to keep moisture from losing and prevent the inside of the box from freezing.
4. Check whether the voltage of the evaporator cold air motor is lower than the standard voltage. When the voltage is lower than the standard voltage, the wind is weak and the air outlet is small, and the cold air cannot be effectively discharged from the refrigeration system, causing the air outlet to freeze and block. At the same time, it is also necessary to check whether the circuit has poor contact.
