Purging the system
22
When using the vacuum pump
1. Completely tighten the flare nuts at
connection point A, B, C and D.
Connect valve core removal tool
to the charging port, then connect
vacuum hose to valve core tool.
Open the schrader valve.
Note: The schrader valve is inside the
charging port.
2. Connect the other charge hose
of manifold valve to the vacuum
pump.
3. Fully open the Low Side handle of
the manifold valve.
4. Operate the vacuum pump to
evacuate. After starting evacuation,
slightly loose the flare nut of the
Low Side valve on the gas pipe
side and check if the air is entering
(Operation noise of the vacuum
pump changes and a compound
meter indicates 0 instead of
minus), then tighten the flare nut.
The procedure verifies if there are
blocks inside the tubes.
5. Make evacuation for 15 minutes or
more and check that the compound
meter indicates -7-3/5 x 10
Microns Hg (-1x10 Pa). After the
evacuation is completed, fully close
the Low Side handle of the manifold
valve and stop the operation of the
vacuum pump.
6. Turn the stem of the packed valve
B about 45
o
counterclockwise
for 6~7 seconds after the gas
comes out, then tighten the flare
nut again. Make sure the pressure
display in the pressure indicator is
For method of using a manifold valve, refer to its operation manual.
a little higher than the atmospheric
pressure. This procedure verifies
if the refrigerant goes through the
tubes correctly.
7. Close the schrader valve, then
remove the valve core tool. Replace
the charging port cap.
8. Fully open the packed valve stems B
and A.
9. Securely tighten the cap of the
packed valve.
Vacuum pump
Charge Hose
Manifold Valve
-76cm/Hg
Charge
Hose
Low Side
High Side
Outdoor unit
Indoor unit