The first step is to evacuate the air in the compressor to ensure it is in a vacuum state before use.
Connect the conduits, and connect the high-pressure gauge and low-pressure gauge to the high-pressure pipe and low-pressure pipe respectively. Open the high-pressure valve and low-pressure valve to eliminate residual gas until the pressure gauge shows zero. Close the high and low pressure valves (note: Do not move too much when opening the high pressure valve, otherwise the refrigeration oil will overflow from the system).
Next, vacuum, connect the yellow tube to the vacuum pump, and turn on the vacuum pump. Open the high-pressure valve and the low-pressure valve, and after vacuuming for 15 minutes, close the high- and low-pressure valves. The pressure gauge maintains a certain negative pressure value for 10 minutes, which proves that the air tightness of the system is good.
The second step is to add refrigeration oil (special) to make it more lubricating and anti-wear.
The third step is to add refrigerant. Start the car and turn on the air conditioning system to the coldest setting with the highest wind speed. After running for a certain period of time, the yellow tube is connected to the bottle opener and the refrigerant. Turn the thimble clockwise to pierce the refrigerant cover, then turn the thimble counterclockwise. Open the low-pressure valve and start charging refrigerant.
Note: Do not place refrigerant on the engine or radiator.