What should I do if the refrigeration system of the medical refrigerated truck is blocked?

What should I do if the refrigeration system of the medical refrigerated truck is blocked?

Medical refrigerated trucks are also common in our lives, because they are used for the transportation of medicines, but if the refrigeration system of the medical refrigerated trucks is blocked, how should we deal with them? Some people are often at a loss for these problems In this regard, let's now take a look at how to deal with the blockage of the refrigeration system of the medical refrigerated truck to talk about it!

Blockage category: The blockage of the refrigerated refrigerated vehicle in the refrigeration system can be divided into three categories: ice blockage, dirty blockage (also known as dirty blockage) and oil blockage. Among them, dirty blockage and oil blockage are divided into two types: blockage and micro blockage.

Blockage reason: due to the moisture in the system exceeding the allowable value (ice blockage), excessive impurities in the medical refrigerated truck (the stolen goods remain in the system during the manufacture of refrigeration equipment, the metal oxides in the pipeline fall off, the molecular sieve or silica gel powder is accidentally entered during the maintenance process Stolen goods, etc.).

Blocked pipelines or pipelines are deformed under pressure (medical refrigerated trucks are badly blocked) and refrigerated oil is overcharged and deteriorated and accumulated in pipe bends, small pipe diameters, or refrigerated oil is cold and sticky at the capillary tube or use time Too long makes the inner wall of the pipeline adhere to too much refrigerating oil (oil blockage) and cause system blockage. Identification of fault phenomena and blockage categories: common features: the condenser is not hot or not hot enough, the evaporator does not frost or partially frost, there is no airflow or small sound of refrigerant flowing, and the low-pressure pressure is low or negative High pressure state, and high pressure (the difference with insufficient refrigerant).

　　 Personality characteristics: ice block: "intermittent repeated refrigeration or periodic non-refrigeration" phenomenon appears. Dirty blockage, bad blockage, oil blockage: Unlike ice blockage, there will be no "intermittent and repeated refrigeration" phenomenon. Once blocked, refrigeration cannot be achieved or the cooling effect is poor.

　　The method of judging whether it is dirty or oily: In a system that uses capillary throttling in the medical refrigerated truck, the capillary is cut off 0.5cm near the dry filter. If there is no refrigerant sprayed out, cut the other end of the filter drier, and there is still no refrigerant sprayed out, then all the refrigerant has leaked; if the refrigerant sprayed out after the capillary is cut, there is more refrigerant oil , It is the oil blockage at the capillary.

　　If refrigerant is sprayed out, there is not much oil, and the medical refrigerated truck can conclude that the capillary tube is dirty and blocked. In the system with expansion valve throttling, first recover the refrigerant, remove the filter screen and solenoid valve at the entrance of the expansion valve, clean and dry with gasoline before reinstalling, and replace the filter drier at the same time. If the test machine is normal, it is Dirty.

　　The oil blockage is generally in the sinking part of the pipe bend and the low-temperature and low-pressure pipe (such as the evaporator). The bad blockage is generally in the filter, solenoid valve, capillary medicine refrigerated truck, expansion valve, and the dead bend and pressure deformation of the pipeline. Generally, the blockage will have frost or condensation. Micro-blocking: The evaporator takes a long time or is not full of frost. The temperature of the condenser, filter drier and compressor is higher than normal, the working current is higher, and it can be cooled, but the effect is poor.

　　The unique feature of the dry filter clogging: Condensation or frosting of the capillary tube is due to the filter's throttling effect, and the capillary tube is equivalent to the evaporator-heat absorption and condensation. Refrigerants have important distinguishing characteristics between air and too much refrigerant: the upper part of the high-pressure tube and the condenser is very hot, while the lower part is obviously not hot. Ice beads sometimes appear at the exit of the capillary. Periodic frost on the evaporator. When the refrigeration system is running, the high-pressure gauge pointer connected to the high-pressure side of the medical refrigerated truck swings slightly from left to right, and the amplitude is slightly unstable; at the same time, the pressure gauge pointer swings faster, and the swing is at the same frequency as the piston movement.