Repair technicians prefer to fill liquid refrigerants from high pressure sides when repairing car air conditioning because this method is faster than filling gas refrigerants from low pressure sides, followed by some step methods and care for refrigerants from high pressure side into air conditioning systems for new hands to learn about vehicle maintenance, and more detailed steps for practical maintenance。
1) when the vacuum operation is completed, the midpipe is removed from the vacuum pump and replaced by the refrigerant injection valve interface, the refrigerant canisters are filled and the refrigerant cans are opened with the injection valves, and the midpipe connections connected to the ptmp are released slightly until the sound of hissing is heard, and the air in the tubing is tightened and drained out。
2) opens the pressure side manual valve of the dmp, and the refrigerant drops high pressure side into the upper side of the system to see if the low pressure pointer rises with the high pressure pointer, and if the low pressure pointer does not return or is very slow, indicates that there is congestion within the system, it should be stopped and overhauled。
If the low-pressure table pointer returns normally with the high-pressure table, the refrigerant can be pushed up to make the refrigerant liquid into the system. Once a prescribed refrigerant is injected, the high pressure side manual valve will be closed and leaking or commissioning will be performed。
The injection of a certain amount of liquid refrigerant from the high pressure side (generally around 200 g) is generally carried out after a vacuum, prior to initial detection, so that the refrigeration system has a quantity of refrigerants and maintains a pressure to facilitate leakage detection with halogen detectors。
Fill liquid refrigerants from high pressure side:
In this way, low-pressure manual valves of the pressure meters are not allowed to be opened, nor are compressors allowed to be operated, or there is a risk of a refrigerant tank bursting。
