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Preparations and Precautions
•
Air and foreign matter in the refrigerant circuit can cause abnormal rise in
pressure, which can damage the air conditioner, reduce its efficiency, and cause
injury.
•
Use a vacuum pump and manifold gauge to evacuate the refrigerant circuit,
removing any condensable gas and moisture from the system.
•
Evacuation should be performed upon initial installation and when unit is
relocated.
Instructions
1. Connect the charge hose of the manifold gauge to service port on the outdoor
units low pressure valve. Use the spare port to mount the micron gauge. Keep
the micron gauge above the manifold to prevent oil from contaminating the
sensor.
2. Connect charge hose from the manifold gauge central port to the vacuum pump.
3. Open both ports of the manifold gauge.
4. Turn on the vacuum pump to evacuate the system.
5. Run the vacuum for at least 15 minutes after the micron gauge reads 350
microns.
6. Close the isolation valve of the manifold, and turn off the vacuum pump and
observe the micron gauge.
7. Wait for 10 minutes then check that there has been no change in system
pressure.
8. If there is a change in system pressure, refer to Gas Leak Check section for
information on how to check for leaks. If there is no change in system pressure,
proceed to the next section.
Evacuation and Opening System
