During the use of industrial chillers, there will be situations such as sudden reduction in refrigeration capacity, or even no refrigeration. In this case, it is recommended to check the expansion valve of the unit to see if there is very serious frost or even freezing. If this happens, it is necessary to consider whether the thermal expansion valve is blocked, and deal with the problem step by step.
1. The main reasons for the blockage of the expansion valve of the industrial chiller:
The blocking failure of the expansion valve of industrial chillers includes two ways: "dirty blocking" and "ice blocking". The main reason for dirty blocking is the existence of residues in the system, for example: welding slag, copper filings, iron filings, fibers, etc. .The main reason for ice blockage is that there is too much moisture (moisture) in the system. The main ways to generate moisture are as follows:
1. The systematic vacuuming time during installation is not enough, and the moisture in the pipeline cannot be exhausted;
2. The welding process of the pipeline connection is not good, and there are air leakage points;
3. When adding refrigerant to the system, the air in the connecting hose is not blown out of the hose.
4. When adding lubricating oil to the system, enter the air.
Dirty blockage of the expansion valve of industrial chillers generally occurs on the filter drier. Before entering the expansion valve, it must pass through the filter drier. The residue in the system is intercepted by the filter, resulting in dirty blockage. The basis for judging dirty blockage Yes, the systemic return air temperature rises, the superheat degree rises, and if the situation is serious, it may also stop the operation. It is forbidden to start the machine until the cleaning of the residue is completed.
The ice block of the expansion valve of the industrial chiller generally occurs at the throttle hole of the expansion valve. The throttle hole is the place with the lowest temperature and the smallest hole diameter in the entire system. Due to the occurrence of ice blockage, the system is no longer refrigerated. The systemic overall temperature rises. As the temperature increases, the ice block will gradually melt, and then the system will restore the cooling capacity. As the systemic overall temperature decreases again, ice blockage will occur again. Therefore, ice blockage is a repeated Procedure.
Second, the elimination method of industrial chiller expansion valve blockage
1. For dirty blockage, if it is not very serious, just replace the filter drier. If it is very serious, it is necessary to clean the residue in the system pipeline again, vacuumize it, and add refrigerant again.
2. For slight ice blockage, a hot towel can be applied to the ice blockage. If the degree of ice blockage is serious, it will affect the normal operation of the system, and the filter dryer should be replaced, and the system pipeline should be removed again. moisture, vacuumize, and add refrigerant again.
The expansion valve of the industrial chiller is one of the four indispensable key components in the entire refrigeration system. Its importance is unquestionable. Its quality will directly affect the operation performance of the entire system. Once a fault occurs, it should be eliminated immediately. The operating life of the industrial chiller, cooling performance and operating costs are particularly important.
Nanjing RICOM Refrigeration Equipment Co., Ltd. is a manufacturer specializing in industrial temperature control technology for 20 years. It implements the modern quality management system S09001: 2008 and environmental system IS014001: 2004 standards to ensure that the enterprise team continues to be in the technical field. Innovation, focus on customer use and satisfaction, and have been unanimously recognized by the industry and customers。
