Simple treatment method after the refrigeration system enters water

Simple treatment method after the refrigeration system enters water

Since the chiller has a water system, there is a possibility that the refrigerant system may enter water when it is used improperly. Therefore, a process guide is formulated for the problem of water ingress in the refrigeration system as a reference for maintenance.

　　 One, analyze the reason

　　 Inspect the entire refrigeration system to confirm the cause of frost damage and find out the leaks.

　　 Two, segmented blowdown

　　 You can use an air compressor to blow water (save nitrogen) until no water mist is deposited. Blow with high-pressure nitrogen to heat the nitrogen while blowing (nitrogen cylinders are prohibited from heating).

　　 Due to the complexity of the refrigerant system piping, a welding torch can be used to blow off the water in certain parts according to the specific situation.

　　 Heating and drying, small parts such as capillary tubes, thermal expansion valves, compressors can be baked and dried in the oven. The refrigerating oil must be replaced after the compressor is dried by water

　　Three, vacuum drying

　　Restore the pipeline, press nitrogen to maintain the pressure to ensure that the system is airtight, and then connect the vacuum pump for vacuum drying. (The dry filter barrel must be added to the front of the vacuum pump to avoid excessive water vapor entering the vacuum pump) During the vacuum drying process, the parts of the pipeline that are likely to contain water can be heated. The time depends on the site.

　　 Four, debugging and running

　　 Confirm that the water in the system is basically removed.

　　 Connect the external drying filter barrel to the system, and replace the desiccant after 5 minutes of operation. At the same time, observe the operating parameters of the unit and pay attention to the operating sound of the compressor. If the dryer filter is cold, the expansion valve is frosted, and there is a pressure difference of more than 0.5 kg before and after the return air filter, it should be shut down immediately.

　　 Repeat the above work, continuously replace the desiccant, the interval time can be gradually increased with the number of times. (Desiccant: Calcium chloride dry particles have a large water absorption capacity, which is used when there is too much moisture at the beginning, and the color-changing silica gel can accurately detect the moisture content, and can be used in the later drying).

　　 Finally, change the desiccant to discoloration silica gel, and run for 24 hours to confirm that the discoloration silica gel maintains its original color

　　 Five, repair is completed

　　Remove the dry filter barrel from the refrigerant pipeline to restore it. Check the amount of supplemental refrigerant. Turn on and check the operating parameters of the machine to confirm that it is normal.

Precautions

　　 Dry filter barrel: Since the gasket of the external dry filter barrel is usually an asbestos pad, the refrigerant is not tightly sealed. Therefore, it is not allowed to run on the system for a long time. It should be removed after maintenance to avoid fluorine leakage.

Prohibition of methanol: the addition of methanol can increase the freezing point of water and relieve ice blockage, but the water in the system has not decreased, and as the circulation time of water in the system increases, it will cause deterioration of refrigerating oil quality, copper plating of system metal parts, and corrosion of the press The leakage of the coil caused serious personal injury.