Installation Manual

BEFORE PERFORMING EVACUATION
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.
Preparations and Precautions
Compound gauge
-76cmHg
pressure
valve
High
pressure
valve
Charge hose
Charge hose
Vacuum
pump
Pressure gauge
e Fig. 6.1
MC MC
Evacuation Instructions
Before using the manifold gauge and vacuum pump,
read their operation manuals to familiarize yourself
with how to use them properly.
Air and foreign matter in the refrigerant circuit can
cause abnormal rises in pressure, which can
gauge to evacuate the refrigerant circuit, removing
any non-condensable gas and moisture from the
system. Evacuation should be performed upon initial
installation and when unit is relocated.
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,
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 the Gas
Leak Checks 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 a 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.
pressure (MAIN) and low pressure (MAIN) 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.
6
Air Evacuation
Page 31
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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