Full Product Manual

 Page 30 
Air Evacuation
Air Evacuation
Safety Precautions
CAUTION
system.
• Use a vacuum pump with a gauge reading
lower than -0.1MPa and an air discharge
capacity above 40L/min.
• The outdoor unit does not need to be
vacuumed. DO NOT open the outdoorunit’s
gas and liquid stop valves.
• Ensure that the Dompound Neter reads
-0.1MPa or below after 2 hours. If after
hours the gauge reading is still above
-0.1MPa, check if there is a gas leak orwater
inside the pipe. If there is no leak,perform
another evacuation for 1 or 2 hours.
• DO NOT
use refrigerant gas to evacuate the
Evacuation Instructions
Before using a manifold gauge and a vacuum
pump, read their operation manuals to make
sure you know how to use them properly.
Manifold Hauge
Compound gauge
-76cmHg
Lowpressure valve
Charge hose
Highpressure valve
Charge hose
Vacuum pump
Pressure gauge
Lowpressure valve
Fig. 9.1
1. Connect the manifold gauge’s charge hose
to the service port on the outdoor unit’s
lowpressure valve.
 Connect the manifold gauge’s charge hose
to the vacuum pump.
 Open the MowQressure side of the manifold
gauge.Keep the highQressure side closed.
 Turn on the vacuum pump to evacuate the
system.
 Run the vacuum for at least 15 minutes, or
until the Dompound Neter reads -76cmHG
(-1x105Pa).
 Close the manifold gauge’s MowQressure
valve and turn off the vacuum pump.
 Wait for 5 minutes, then check that there has
been no change in system pressure.
NOTE: If there is no change in system
pressure, unscrew the cap from the packed
valve (highpressure valve). If there is a change
in system pressure, there may be a gas leak.
8. Insert Bhexagonal wrench into the packed valve
(highpressure valve) and open the valve by
turning the wrench 1/4 counterclockwise.
Listen for gas to exit the system, then close the
valve after 5 seconds.
Flare nut
Cap
Valve body
Valve stem
Fig. 9.2
9. Watch the pressure gauge for one minute to make
sure that there is no change in pressure. It should
read slightly higher than the atmospheric pressure.
10.Remove the charge hose from the service port.
11.Using a hexagonal wrench, fully open both the
high-pressure and low-pressure valves.
OPEN VALVE STEMS GENTLY
When opening the valve stems, turn the hexagonal
wrench until it hits against the stopper. DO NOT
try to force the valve to open further.
12.Tighten the valve caps by hand, then
tighten them using the proper tool.
9