Panasonic Cs W7bkp Cs W9bkp Cs W12bkp Repair Manual

							11.1.2. Pumping down
Procedure:
 1. Confirm that both the 2-way and 3-wayvalves are set to
the opened position.
 • Remove the valve stem caps and confirm that the valve
stems are in the opened position.
 • Be sure to use a hexagonal wrench to operate the valve
stems.
 2. Operate the unit for 10 to 15 minutes.
 3. Stop operation and wait for 3 minutes, then connect the
charge set to the service port of the 3-wayvalve.
 • Connect the charge hose with the push pin to the Gas
service port.
 4. Air purging of the charge hose.
 • Open the low-pressure valveon the charge set slightly
to purge air from the charge hose.
 5. Set the 2-wayvalve to theclosed position. 6. Operate the air conditioner at the cooling cycle and
stop it when the gauge indicates 0 MPa (0 kg/cm
2G).
If the unit cannot be operated at the cooling condition
(weather is rather cool), shortthe Pumping Down pins
on the Main Control P.C.B.
(Simply press the pumping down button if it is
equipped.)
So that the unit can be operated.
 7. Immediately set the 3-way valve tothe closed position.
 • Do this quickly so that the gauge ends up indicating 0.1
MPa (1 kg/cm
2G) to 0.3 MPa (3 kg/cm2G).
 8. Use refrigerant reclaiming equipment to collect
refrigerant from indoor unit and pipes.
 9. Disconnect the charge set, and mount the 2-way and 3-
way valve’s stemcaps and the service port caps.
 • Use a torque wrench to tighten the service port cap to a
torque of 18 N.m.
 • Be sure to check for gas leakage.
 10. Disconnect pipes from indoor unit and outdoor unit.
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CS-W7BKP CU-W7BKP5 / CS-W9BKP CU-W9BKP5 / CS-W12BKP CU-W12BKP5 
						

							11.1.3. Evacuation of Re-installation
WHEN REINSTALLING AN AIR CONDITIONER, BE SURE TO
EVACUATE THE AIR INSIDE THE INDOOR UNIT AND PIPES
in the following procedure.
 1. Connect a charging hose with a push pin to the Low
side of a charging set and the service port of the 3-way
valve.
 • Be sure to connect the endof 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 switchof the vacuum pump and
make sure that the needle in the gauge moves from 0
MPa (0 cmHg) to -0.1 MPa (-76 cmHg). Then evacuate
the air for approximately ten minutes.
 4. Close the Lowside valveof the charging set and turn
off the vacuum pump. Make sure that the needle in the
gauge does not move after approximately five minutes.
BE SURE TO TAKE THISPROCEDURE IN ORDER TO
AVOID GAS LEAKAGE.
 5. Disconnect the charging hose from the vacuum pump.
 6. Charge the pipes and indoor unit with gas refrigerant
from 3-wayvalve serviceport, and then discharge the
refrigerant until low side (gas side) gauge needle
indicates 0.3 MPa (3 kg/cm
2).If air remain in the indoor unit and refrigeration pipes, it will
affect the compressor, reduce tocooling capacity, and could
lead to a malfunction.
 7. Tighten the service port cap ata torque of 18 N.m with
a torque wrench.
 8. Remove the valvecaps of the2-wayvalve and the 3-
way valve.Position both of thevalves to“open” using
a hexagonal wrench (4 mm).
 9. Mount thevalve capsonto the 2-wayand 3-way valves.
 • BE SURE TO USE REFRIGERANT RECLAIMING
EQUIPMENT WHILE DISCHARGING THE
REFRIGERANT.
 • Purge the air from charge set’s centre hose.
 • Be sure to check for gas leakage.
CautionIf gauge needle does not move from 0 MPA (0 cmHg)
to -0.1 MPa (-76 cmHg) 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.
Procedure:
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CS-W7BKP CU-W7BKP5 / CS-W9BKP CU-W9BKP5 / CS-W12BKP CU-W12BKP5 
						

							(Lack of refrigerant in the refrigeration cycle)
Procedure:
 1. Confirm that both the 2-way and 3-wayvalves are set to
the open position.
 2. Connect the charge set tothe 3-way valve’s service
port.
 • Leave the valve on the charge set closed.
 • Connect the charge hose with the push-pin to the
service port.
 3. Connect the charge set’s centre hose to refrigerant
reclaiming equipment.
 • Purge the air from charge hose.
 4. Open the valve(Low side) on the charge set and
discharge the refrigerant until the gauge indicates 0.05
MPa (0.5 kg/cm
2G) to 0.1 MPa (1 kg/cm2G).
 • If there is no air in the refrigeration cycle (the pressure
when the air conditioner is not running is higher than 0.1
MPa (1 kg/cm
2G), discharge the refrigerant until the
gauge indicates 0.05 MPa (0.5 km/cm2G) to 0.1 MPa (1
kg/cm2G). If this is the case, it will not be necessary to
apply a evacuation.
 • Discharge the refrigerant gradually; if it is discharged
too suddenly, the refrigeration oil will also be
discharged.
 5. Turn on refrigerant reclaiming equipment.
11.1.4. Balance refrigerant of the 2-way, 3-way valves
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CS-W7BKP CU-W7BKP5 / CS-W9BKP CU-W9BKP5 / CS-W12BKP CU-W12BKP5 
						

							(No refrigerant in the refrigeration cycle)
Procedure:
 1. Connect the vacuum pump to the charge set’s centre
hose.
 2. Evacuation for approximately one hour.
 • Confirm that the gauge needle has moved toward -0.1
MPa (-76 cmHg) [vacuum of 4 mmHg or less.]
 3. Closethe valve(Low side) on thecharge set, turn off
the vacuum pump, and confirm that the gauge needle
does not move (approximately 5 minutes after turning
off the vacuum pump).
 4. Disconnect the charge hose from the vacuum pump.
 • Vacuum pump oil
If the vacuum pump oilbecomes dirtyor depleted,
replenish as needed.
11.1.5. Evacuation
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CS-W7BKP CU-W7BKP5 / CS-W9BKP CU-W9BKP5 / CS-W12BKP CU-W12BKP5 
						

							(After Evacuation)
Procedure:
 1. Connect the charge hose to the charging cylinder.
 • Connect the charge hose which you disconnected from
the vacuum pump to the valve at the bottom of the
cylinder.
 2. Purge the air from the charge hose.
 • Open the valve at the bottom of the cylinder and press
the check valve on the charge set to purge the air (be
careful of the liquid refrigerant).
 3. Open the valve(Low side) on thecharge set and charge
the system with liquid refrigerant.
 • If the system cannot be charged with the specified
amount of refrigerant, it can be charged with a little at a
time (approximately 150 g each time) while operating
the air conditioner in the cooling cycle; however, one
time is not sufficient, wait approximately 1 minute and
then repeat the procedure. (pumping down-pin)
This is different from previous procedures. Because you are
charging with liquid refrigerant fromthe gas side, absolutely do
no attempt to charge with large amount of liquid refrigerant
while operating the air conditioner.
 4. Immediately disconnect the charge hose from the 3-
way valve’s service port.
 • Stopping partwaywill allow the refrigerant to be
discharged.
 • If the system has been charged with liquid refrigerant
while operating the air conditioner, turn off the air
conditioner before disconnecting the hose.
 5. Mount thevalve stemcaps and the service port cap.
 • Use torque wrench to tighten the service port cap to a
torque of 18 N.m.
 • Be sure to check for gas leakage.
11.1.6. Gas charging
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CS-W7BKP CU-W7BKP5 / CS-W9BKP CU-W9BKP5 / CS-W12BKP CU-W12BKP5 
						

							Required tools: hexagonal wrench, adjustable wrench, torque
wrenches, wrench to hold the joints and gas leak detector.
The additional gas for air purging has been charged in the
outdoor unit.
However, if the flare connections have not been done correctly
and there gas leaks, a gas cylinder and the charge set will be
needed.
 1. Recheck the piping connections.
 2. Open thevalve stemof the2-wayvalvecounter-
clockwise approximately 90°, wait 10 seconds, and
then set it to closed position.
 • Be sure to use a hexagonal wrench to operate the valve
stem.
 3. Check for gas leakage.
 • Check the flare connection for gas leakage.
 4. Purge the air from the system
 • Set the 2-way valve to the open position and remove the
cap from the3-wayvalve’s service port.
 • Using the hexagonal wrench to press the valve core pin,
discharge for three seconds and then wait for one
minute.
Repeat this three times.
 5. Use torque wrench to tightenthe service port cap to a
torque of 1.8 kg.m. (18 N.m).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 coolingcapacity, and could lead to a
malfunction.
 6. Set the 3-wayvalve to theopened position.
 7. Mount thevalve stemnuts to the2-way and 3-way
valves.
 8. Check for gas leakage.
 • At this time, especially check for gas leakage from the 2-
way and 3-way’s stem nuts,and from the service port
cap.
CautionIf gas leakage is discovered in step (3) above, take
the following measures:
If the leaks stop when the piping connections are
tightened further, continue working from step (4).
If the gas leaks do not stop when the connections are
retightened, repair the location of the leak, discharge
all of the gas through the service port, and then
recharge with the specified amount of gas from a gas
cylinder.
11.2. Air Purging of the Piping and Indoor Unit
11.2.1. Air purging (Installation)
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:
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CS-W7BKP CU-W7BKP5 / CS-W9BKP CU-W9BKP5 / CS-W12BKP CU-W12BKP5 
						

							 1. Confirm that both the 2-way and 3-wayvalves are set to
the opened position.
 • Remove the valve stem caps and confirm that the valve
stems are in the opened position.
 • Be sure to use a hexagonal wrench to operate the valve
stems.
 2. Operate the unit for 10 to 15 minutes.
 3. Stop operation and wait for 3 minutes, then connect the
charge set to the service port of the 3-wayvalve.
 • Connect the charge hose with the push pin to the Gas
service port.
 4. Air purging of the charge hose.
 • Open the low-pressure valveon the charge set slightly
to purge air from the charge hose. 5. Set the 2-wayvalve to theclose position.
 6. Operate the air conditioner at the cooling cycle and
stop it when the gauge indicates 1 kg/cm
2G (0.1 MPa).
 7. Immediately set the 3-way valve tothe closed position.
 • Do this quickly so that the gauge ends up indicating 3 to
5 kg/cm
2G (0.3 to 0.5 MPa).
 8. Disconnect the charge set, and mount the 2-way and 3-
way valve’s stemnuts and the service port caps.
 • Use a torque wrench to tighten the service port cap to a
torque of 1.8 kg.m (18 N.m).
 • Be sure to check for gas leakage.
11.2.2. Pumping down (Re-installation)
Procedure:
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CS-W7BKP CU-W7BKP5 / CS-W9BKP CU-W9BKP5 / CS-W12BKP CU-W12BKP5 
						

							11.2.3. Re-air purging (Re-installation)
 1. Confirm that both the 2-way and 3-wayvalves are set to
the closed position.
 2. Connect the charge set and a charging cylinder to the
service port of the 3-wayvalve.
 • Leave the valve on the charging cylinder closed.
 3. Air purging.
 • Open the valves on the charging cylinder and the
charge set. Purge the air by loosening the flare nut on
the 2-wayvalve approximately 45° for3 seconds then
closing it for 1 minute; repeat 3 times.
 • After purging the air, use a torque wrench to tighten the
flare nut onthe 2-wayvalve.
 4. Check for gas leakage.
 • Check the flare connections for gas leakage. 5. Discharge the refrigerant.
 • Close the valve on the charging cylinder and discharge
the refrigerant until the gauge indicates 3 to 5 kg/cm
2G
(0.3 to 0.5 MPa)
 6. Disconnect the charge set and the charging cylinder,
and set the 2-way and 3-wayvalves tothe open
position.
 • Be sure to use a hexagonal wrench to operate the valve
stems.
 7. Mount thevalve stemnuts and the service port cap.
 • Be sure to use a torque wrench to tighten the service
port cap to a torque 1.8 kg.m (18 N.m).
 • Be sure to check for gas leakage.
Procedure:
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CS-W7BKP CU-W7BKP5 / CS-W9BKP CU-W9BKP5 / CS-W12BKP CU-W12BKP5 
						

							(Gas leakage)
 1. Confirm that both the 2-way and 3-wayvalves are set to
the open position.
 2. Connect the charge set tothe 3-way valve’s service
port.
 • Leave the valve on the charge set closed.
 • Connect the charge hose with the push pin to the
service port.
 3. Open the valves(Low side) on the charge set and
discharge the refrigerant until the gauge indicates 0.5
to 1 kg/cm
2G (0.05 to 0.1 MPa) .
 • If there is no air in the refrigeration cycle [ the pressure
when the air conditioner is not running is higher than 1
kg/cm
2G (0.1 MPa) ], discharge the refrigerant until the
gauge indicates 0.5 to 1 kg/cm2G (0.05 to 0.1 MPa). If
this is the case, it will not be necessary to apply a
evacuation.
 • Discharge the refrigerant gradually; if it is discharged
too suddenly, the refrigeration oil will be discharged.
11.2.4. Balance refrigerant of the 2-way, 3-way valves
Procedure:
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CS-W7BKP CU-W7BKP5 / CS-W9BKP CU-W9BKP5 / CS-W12BKP CU-W12BKP5 
						

							(No refrigerant in the refrigeration cycle)
 1. Connect the vacuum pump to the charge set’s centre
hose.
 2. Evacuation for approximately one hour.
 • Confirm that the gauge needle has moved toward -0.1
MPa (-76 cmHg) [vacuum of 4 mmHg or less.]
 3. Closethe valve(Low side) on thecharge set, turn off
the vacuum pump, and confirm that the gauge needle
does not move (approximately 5 minutes after turning
off the vacuum pump).
 4. Disconnect the charge hose from the vacuum pump.
 • Vacuum pump oil
If the vacuum pump oilbecomes dirtyor depleted,
replenish as needed.
11.2.5. Evacuation (Installation)
Procedure:
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CS-W7BKP CU-W7BKP5 / CS-W9BKP CU-W9BKP5 / CS-W12BKP CU-W12BKP5