During long-term use of the rapid temperature cycling test chamber, the refrigeration system may be blocked. The main reasons for the blockage of the refrigeration system are ice blockage, impurity blockage, or oil blockage of the throttle valve, or dirty blockage of the drying filter.
Now let's analyse the causes and solutions of the blockage in the refrigeration system.
No.1 Causes of ice blockage failure
The main reason for ice blockage failure is that the refrigeration system contains excessive water. As the refrigerant continues to circulate, the temperature at the outlet of the expansion valve is too low, causing water to freeze and gradually increase, gradually completely blocking the expansion valve. Due to the blockage, the exhaust pressure increases, and there is no refrigerant flowing into the evaporator. The ice begins to melt, forming a periodic blockage phenomenon.
How to troubleshoot ice blockage?
1. Using a drying box for heating and drying: Put the compressor, condenser, evaporator, expansion valve, and return pipe in the refrigerator system into the drying box for heating and drying.
2. Heating and secondary vacuum pumping methods are used to remove moisture from various components of the refrigeration system.
No.2 Causes of impurity blokage failure
The dirty blockage fault is caused by excessive impurities in the refrigeration system. The main sources of impurities are dust and metal filings during the manufacturing process of refrigeration equipment, and the internal and external surfaces of various components are not cleaned during the processing process.
How to troubleshoot dirty and clogged expansion valves?
1.Use high-pressure nitrogen to blow out the dirt from the blocked expansion valve, clean and dry all components of the refrigeration system, and then reassemble and weld them.
2.If the expansion valve is seriously blocked, it is recommended to replace the expansion valve or adopt other methods.
No.3 Causes of oil blockage failure
Main cause: Severe wear of compressor cylinder block or excessive fit clearance between piston and cylinder
How to troubleshoot oil blockage?
1. Clean the refrigerant oil in the system.
2. Even if the filter is replaced with a new one, use high-pressure nitrogen to blow out some of the refrigerant oil accumulated in the condenser. When introducing nitrogen, use a hairdryer to heat the condenser.