Operation steps of vacuum drying of Reducing Fwmale Adapter
The copper pipe can enter the vacuum drying step after passing the airtight test twice, and it should be confirmed whether the valve is actually closed.
1. If the outdoor unit is not vacuumed, first confirm that the shut-off valves on the gas side and the liquid side of the outdoor unit are closed tightly;
2. Drain the nitrogen, connect the pressure gauge connector to the fluorine injection nozzle of the outdoor unit and the small valve, and connect a vacuum pump to vacuum at high and low pressure N.
3. Turn on the vacuum pump and turn on the "LO" and "HI" knobs;
4. After the vacuum reaches -0.1MPa, continue pumping for 0.5-1.0 hours, then turn off the high-pressure end "VH" and low-pressure end "VL" knobs, and stop the vacuum pump;
5. Change the hose connected to the vacuum pump to the freon filling tank, drain the air from the hose, turn on the "VL" knob on the low pressure end, and fill the system pipeline with freon, and then close it when the pressure reaches 0.0kgf/cm2 Low voltage end "VL" knob;
6. Reconnect the hose connecting the freon filling tank to the vacuum pump, turn on the vacuum pump, turn on the “VH” knob on the high pressure end, pump for 30 minutes at the high pressure end, and then turn on the “VL” knob on the low pressure end to pump the low pressure end. The vacuum degree reaches -0.1MPa.
7. If the vacuum degree reaches -0.1MPa or lower, the vacuuming is completed, turn off the vacuum pump, leave it for 1 hour, and then check whether the vacuum degree changes. Confirm that the vacuum pump can reach -755mmHg or less after working for more than 1 hour; if it still does not reach -755mmHg or less for more than 3 hours, it means that there is water mixing or air leakage, and it needs to be checked.
8. If moisture is mixed in, nitrogen must be used for "vacuum destruction": that is, after vacuum drying, add nitrogen to 0.5kgf/cm2, and then vacuum. This operation is repeated until the vacuum degree of -755mmHg is maintained and the pressure does not rise.
9. After the vacuum is completed, first close all the valves of the meter splitter, and then close the vacuum pump.