3-Way Valves; Evacuation Of Installation - Panasonic CS-C181KE Service Manual

CS-C181KE

1 Evacuation of Installation

When installing an air conditioner, be sure to evacuate the air inside the indoor unit and pipes in the following procedure.
Required tools: hexagonal wrench, adjustable wrench,
torque wrenches, wrench to hold the
joints, gas leak detector, and charging
set.
Vacuum pump
Service port cap
Be sure, using a torque wrench to tighten the service port cap (after using the service port), so that it prevents the gas
leakage from the refrigeration cycle.
Procedure:
(1) Connect a charging hose with a push pin to the
Low and High sides of a charging set and the
service ports of a 3-way valves.
Be sure to connect the end of the charging hose
with the push pin to the service port.
(2) Connect the centre hose of the charging set to
a vacuum pump.
(3) Turn on the power switch of the vacuum pump and
make sure that the needle in the gauge moves
from 0 cmHg (0 MPa) to –76 cmHg (–0.1 MPa). Then
evacuate the air for approximately 10 minutes.
(4) Close the valve of both the Low and High sides of
the charging set and turn off the vacuum pump.
Make sure that the needle in the gauge does not
move after approximately 5 minutes.
BE SURE TO TAKE THIS PROCEDURE IN ORDER
TO AVOID REFRIGERANT GAS LEAKAGE.
(5) Disconnect the charging hose from the vacuum
pump and from the service ports of the

3-way valves.

(Indoor unit)
(Liquid side)
(Gas side)
OPEN
Lo Hi
The air in the indoor unit and in the piping must be
purged. If air remains in the refrigeration pipings, it will
affect the compressor, reduce the cooling capacity, and
could lead to a malfunction.
3-way valve
3-way valve
Close
OPEN
(6) Tighten the service port caps of both the 3-way
valves at a torque of 18 N•m with a torque wrench.
(7) Remove the valve caps of both the 3-way valves.
Position both of the valves to "open" using a
hexagonal wrench (4 mm).
(8) Mount valve caps onto both of the 3-way valves.
Be sure to check for gas leakage.
Caution
If gauge needle does not move from 0 cmHg
(0 MPa) to –76 cmHg (–0.1 MPa) in step (3)
above, take the following measures:
If the leaks stop when the piping connections are
tightened further, continue working from step (3).
If the leaks do not stop when the connections are
retightened, repair the location of the leak.
– 23 –
(Outdoor unit)
Close