29
AIR PURGING
When relocate the unit to another place,
perform evacuation using vacuum pump.
Make sure the refrigerant added into the air
conditioner is liquid form in any case.
(Not applicable to the units adopt freon R22 )
Open the valve stem until it hits against the
stopper. Do not try to open it further.
Securely tighten the valve stem cap with a
spanner or the like.
Valve stem cap tightening torque (See
Tightening torque table in previous page ).
Outdoor
unit
Indoor
unit
Refrigerant
Flare nut
Stopper
Cap
Valve body
Packed valve
Half union
Gas side
Liquid side
A
C
D
B
Valve stem
Fig.56
Fig.57
When Using the Vacuum Pump
(For method of using a manifold valve, refer
to its operation manual.)
1. Completely tighten the flare nuts, A, B, C, D,
connect the manifold valve charge hose to a
charge port of the low-pressure valve on the
gas pipe side.
2. Connect the charge hose connection to the
vacuum pump.
3. Fully open the handle Lo of the manifold valve.
4. Operate the vacuum pump to evacuate. After
starting evacuation, slightly loose theflare nut
of the Lo valve on the gas pipe side and
check that the air is entering(Operation noise
of the vacuum pump changes and a
compound meter indicates 0 instead of minus)
5. After the evacuation is complete, fully close
the handle Lo of the manifold valve and stop
the operation of the vacuum pump. Make
evacuation for 15 minutes or more and check
that the compound meter indicates
5
-76cmHg (-1x10 Pa).
6. Turn the stem of the packed valve B about
o
45 counterclockwise for 6~7 seconds after
the gas coming out, then tighten the flare nut
again. Make sure the pressure display in the
pressure indicator is a little higher than the
atmosphere pressure.
7. Remove the charge hose from the Low
pressure charge hose.
8. Fully open the packed valve stems B and A.
9. Securely tighten the cap of the packed valve.
Manifold valve
Compound meter
-76cmHg
Handle Lo
Handle Hi
Charge hose
Charge hose
Vacuum pump
Pressure gauge
Low pressure valve
Fig.58
Caution in handling the packed valve