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AIR EVACUATION
7
7.1 Preparations & Precautions
Air and foreign matter in the refrigerant circuit can cause abnormal rises in
pressure, which can damage the air conditioner, reduce its eciency, and cause
injury. Use a vacuum pump and manifold gauge to evacuate the refrigerant circuit,
removing any non-condensible gas and moisture from the system. Evacuation
should be performed upon initial installation and when unit is relocated.
; Check to make sure that both high-pressure and low-pressure pipes
between the indoor and outdoor units are connected properly in
accordance with the Refrigerant Piping Connection section of this manual.
; Check to make sure all wiring is connected properly.
BEFORE PERFORMING EVACUATION
7.2 Evacuation Instructions
Before using the manifold gauge and vacuum pump,
read their operation manuals to familiarize yourself
with how to use them properly.
1. Connect the charge hose of the manifold gauge
to service port on the outdoor unit’s low-pressure
valve.
2. Connect another charge hose from the manifold
gauge to the vacuum pump.
3. Open the low-pressure side of the manifold gauge.
Keep the high-pressure side closed.
4. Turn on the vacuum pump to evacuate the system.
5. Run the vacuum for at least 15 minutes, or until the
Compound Meter reads -76 cmHG (-105 Pa).
6. Close the low-pressure side of the manifold gauge,
and turn o the vacuum pump.
7. Wait for 5 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, unscrew the cap from the packed valve
(high-pressure valve).
9. Insert hexagon wrench into the packed valve (high-
pressure valve) and open the valve by turning the
wrench in a 1/4 counter clockwise turn. Listen for
gas to exit the system, then close the valve after 5
seconds.
10. Watch the Pressure Gauge for one minute to make
sure that there is no change in pressure. The
Pressure Gauge should read slightly higher than
atmospheric pressure.
11. Remove the charge hose from the service port.
12. Using hexagon wrench, fully open both the high-
pressure and low-pressure valves.
13. Tighten valve caps on all three valves (service port,
high-pressure, low-pressure) by hand. You may
tighten it further using a torque wrench if needed.
OPEN VALVE STEMS GENTLY
When opening valve stems, turn the hexagonal
wrench until it hits against the stopper.
DO NOT try to force the valve to open further.
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