What are the steps for evacuating a car air conditioning system?
1 Answers
The steps for evacuating a car air conditioning system are as follows: 1. Connect the high and low pressure hoses of the manifold gauge to the high and low pressure side service valves respectively, and connect the center hose to the vacuum pump. 2. Open the high and low pressure manual valves on the manifold gauge, start the vacuum pump, and observe the pointer of the low pressure gauge (process gauge), which should show vacuum. 3. After continuous evacuation for 5 minutes, the low pressure should reach 0.03MPa (vacuum degree), and the high pressure should be slightly below zero. If the high pressure gauge cannot go below the zero mark, it indicates a blockage in the system. Stop the evacuation, repair the system, and then resume evacuation. 4. After the vacuum pump operates for 15 minutes, the low pressure gauge pointer should be between 0.001~0.02MPa. If this value is not achieved, close the high and low pressure manual valves and observe the low pressure gauge pointer. If the pointer rises, it indicates a vacuum loss and a leak in the system. Stop the evacuation and resume only after repairing the leak. 5. When the system pressure approaches vacuum, close the high and low pressure manual valves and hold the pressure for 5~10 minutes. If the low pressure gauge pointer does not move, open the high and low pressure manual valves, start the vacuum pump, and continue evacuation for no less than 30 minutes.
