Central air conditioning refrigeration system blocking causes and treatment methods

In the process of using central air conditioning, we will encounter various blocking problems, pipeline blocking, compressor blocking and so on. This small series will explain to you how to repair the central air conditioning refrigeration system blockage, let's have a look!

1. The expansion valve hole is blocked

【 Reason analysis 】

(I the main parts of the refrigeration system are boring and improperly handled; (2) The vacuum of the whole system is not complete;

(3) Excess water content of refrigerant.

Intermittent refrigeration: The refrigeration is normal at the beginning, and after continuing for a period of time, the entire surface of the expansion valve begins to frost, the transpiration temperature is below O ° C, and the water is collected at the expansion valve hole, and the valve hole is gradually blocked. Then there is defrosting at the transpiration, and no air flow is heard, and the suction pressure is a vacuum. Use hot water to heat the expansion valve, so that the ice at the valve hole can be melted, and the normal cooling can be done.

[Treatment method] A filter with moisture absorbent (silica gel, anhydrous calcium chloride) is inserted into the refrigeration system

The apparatus will be the moisture within the system

Strain it out, then remove the filter.

Second, the expansion valve filter is dirty and blocked

[Analysis of the causes of the problem] There is a lot of coarse powdery dirt in the system, which will block the entire filter, and the refrigerant can not pass through, resulting in no refrigeration.

[Discrimination method] Knock on the expansion valve, sometimes through some refrigerant to complete cooling. [Treatment method] Remove the filter to clean, dry, reload the system from scratch. Three, dry filter blocking

[Analysis of the cause of the problem] The dry agent is used for a long time and forms a paste to seal the filter, or the dirt gradually accumulates in the filter to cause obstruction.

[Discrimination method] After tapping the filter, ventilation will appear, and the filter is cooler than normal when touched by hand. [Treatment method] Remove the filter to clean, dry, replace the new dry agent, put into the system. 4. Refrigerant leakage in the temperature sensing bag of the expansion valve

[Fault cause analysis] After the temperature sensing agent in the expansion valve temperature sensing bag leaks, the two forces below the diaphragm push the diaphragm upward, and the valve hole is closed, and the refrigerant in the system cannot pass through, resulting in no cooling. At this time, the expansion valve does not frost, the low pressure is a vacuum, and the air flow is not heard in the evaporator

[Discrimination method]

1 Loosen the expansion valve inlet to see if there is refrigerant ejection, yes, quickly closed. (2) Open the expansion valve outlet to see if there is refrigerant ejector, no, it is blocked.

[Treatment] Shut down the stop valve, remove the expansion valve to check whether the filter is blocked, if not, you can use the mouth to blow the expansion valve inlet to see whether it is ventilated. It can also be visually inspected or disassembled and replaced when damaged.

The above is a small series on the central air conditioning refrigeration system blocking causes of analysis and treatment of all the content! If you want to know a lot about central air conditioning maintenance, please pay attention to our website.