Panasonic Cs C9dkzw Cu 2c18dkh Cu 3c20dkh Repair Manual

							 1. The inside and outside connecting cable can be connected
without removing the front grille.
 2. Connecting cable between indoor unit and outdoor unit
shall be approved polychloroprene sheathed 4 × 1.5 mm
2
flexible cord, typedesignation 245 IEC 57 or heavier cord.
 • Ensure the color of wires of outdoor unit and the
terminal Nos. are the same to the indoor’s respectively.
 • Earth lead wire shall be longer than the other lead wires
as shown in the figure forthe electrical safetyin case of
the slipping out of the cord from the anchorage.
 • Secure the cable onto the control board with the holder
(clamper).
INSTALLATION OFSUPER ALLERU-BUSTER FILTER
 1. Open the front panel.
 2. Remove the air filters.
 3. Remove Supersonic air purifying device.
 4. Open the Supersonicair purifying device frame.
 5. Insert the super alleru-buster filter and close the Supersonic
air purifying device frame as shown in illustration at right.
10.5.5. CONNECT THE CABLE TO THE INDOOR UNIT
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							HOW TO TAKE OUT FRONT GRILLE
Please follow the steps below to take out front grille if
necessary such as when servicing.
 1. Open the intake grille and remove the screw at the front of
the front grille.
 2. Set the vertical airflow direction louver to the horizontal
position.
 3. Slide down the 2 caps on the front grille as shown in the
illustration below, and then remove the 2 mounting screws.
 4. Pull the lower section of the front grille towards you to
remove the front grille.
When reinstalling the front grille, first set the vertical
airflow direction louver to the horizontal position and
then carry out above steps 2 -3 in the reverse order.
AUTO SWITCH OPERATION
The below operations will be performed by pressing the
“AUTO” switch.
 1. AUTO OPERATION MODE
The Auto operation will be activated immediately once the
Auto Switch is pressed.
 2. TEST RUN OPERATION (FOR PUMP DOWN/SERV ICING
PURPOSE)
The Test Run operation will be activated if the Auto Switch
is pressed continuously for more than 5 sec. A “pep” sound
will occur at the fifth sec., inorder to identifythe starting of
Test Run operation
 3. REMOTE CONTROLLER RECEIVING SOUND ON/OFF
The ON/OFF of Remote Controller receiving sound can be
change over by the following steps:
 a. Release the Auto Switch after Test Run operation is
activated.
 b. Then, within 20 sec. after (a), press Auto Switch for
more than 5 sec.
A “beep” “beep” sound will occur at the fifth sec., then
release the Auto switch.
 c. Within 20 sec. after (b), press Auto Switch again.
Everytime Auto Switch is pressed(within 20 sec.
interval), remote controller receiving sound status will be
reversed between ON and OFF.
Long “beep” sound indicates that remote controller
receiving sound is OFF.
Short “beep” sound indicates that remote controller
receiving sound is ON.
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							10.6. Outdoor unit
10.6.2. INSTALL THE OUTDOOR UNIT
 • After selecting the best location, start installation according
to Indoor/Outdoor Unit Installation Diagram.
 1. Fix the unit on concreteor rigid frame firmly and horizontally
by bolt nut. (ø10 mm).
 2. When installing at roof, please consider strong wind and
earthquake. Please fasten theinstallation standfirmly with
bolt or nails.
10.6.3. CONNECTING THE PIPING
Connecting The Piping To Indoor Unit
Please make flare after inserting flare nut (locate at joint portion
of tube assembly) onto the copper pipe. (In case of using long
piping)
Connect the piping
 • Align the center of piping and sufficiently tighten the flare
nut with fingers.
 • Further tighten the flare nut with torque wrench in specified
torque as stated in the table.
Connecting the Piping to Outdoor Unit
 1. Align the center of the piping and sufficiently tighten the
flare nut with fingers.
 2. Finally, tighten the flare nut with torque wrench until the
wrench clicks.
 • W hen tightening the flare nut with torque wrench,
ensure the direction for tightening follows the arrow on
the wrench.
MODELPiping size (Torque)
GasLiquid
CS-C9DKZW3/8” (42 N.m)1/4” (18 N.m)
10.6.1. SELECT THE BEST LOCATION
(Refer to “Select the best location” section)
CautionThe CU-3C20DKH/C9DKZW have different cooling capacities depending on the connection to A1,A2and/or B on CU-
3C20DKH individually.
(Refer to SPECIFICATIONS on CATALOG)
 1. The Cooling Capacity of Indoor Unit connecting “B” on CU-3C20DKH (Called B unit) is different from that of A
1and A2Units.
 2. A
1and A2Units share the same compressor, their cooling capacities thus change depending on whether one, the other,
or both of the units is in use.
 3. Reflect the B or A (A
1and/or A2) on the Indoor Unit for later reference.
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							CUTTING AND FLARING THE PIPING
 1. Please cut using pipe cutter and then remove the burrs.
 2. Remove the burrs by using reamer. If burrs is not removed, gas leakage may be caused.
Turn the piping end down to avoid the metal powder entering the pipe.
 3. Please make flare after inserting the flare nut onto the copper pipes.
10.6.4. AIR PURGING OF THE PIPING AND INDOOR UNIT
1) Checking gas leakage
 1. Remove the service-portcap from both3-wayvalves.
 2. Connect the manifold gauge set tothe service port ofLiquid side3-way valve.
 3. Connect the charging cylinder to the manifold gauge set and open the valve of the cylinder.
 4. Open the low pressure side valve of the manifold gauge of approx. 10 seconds and then close.
 5. Check a gas leakage of theconnecting portion of pipings with the gas-leak detector.

 1. Measure the pressure.
 2. Keep it for 5-10 minutes.
 • Ensure if the pressure indicated on the gauge is as same as that measured at first time.
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							The air which contains remaining moisture in the refrigeration
cycle may cause a malfunction on the compressor.
 1. To purge the air, push the pin on the gas side 3-way valve
for three seconds using with a hexagonal wrench and set it
free for one minute.
 • Repeat this three times.
 2. To balance the refrigerant, close the low pressure side
valve on the manifold gauge and release a refrigerant from
the piping through service port until the gauge indicates
0.49 ~ 0.294 MPa.
 3. Set theboth 3-wayvalves to open position with the
hexagonal wrench for the unit operation.
2) Air purging
10.6.5. CONNECT THE CABLE TO THE OUTDOOR UNIT
 1. Remove the control board cover from the unit by loosening the screw.
 2. Connecting cable between indoor unit and outdoor unitshall be approved polychloroprenesheathed flexiblecord, type
designation 245 IEC 57 or heavier cord (4 × 1.5 mm
2).
Power supply cord cable use 3 × 1.5 mm
2flexible cord, typedesignation 245 IEC 57 or heavier cord.
 3. Secure the cable onto the control board with the holder (clamper).
 4. Confirm the SW1 Switchat AUTO position. (CU-3C20DKH)
 5. Attach the control board cover back to the original position with the screw.
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							10.6.6. PIPE INSULATION
CHECK THEDRAINAGE
 • Open front panel and remove air filters.
(Drainage checking can be carriedout without removing the
front grille.)
 • Pour a glass of water into the drain tray-styrofoam.
 • Ensure that water flows out from drain hose of the indoor
unit.
EVALUATION OF THEPERFORMANCE
 • Operate the unit at cooling operation mode for fifteen
minutes or more.
 • Measure the temperature of the intake and discharge air.
 • Ensure the difference between the intake temperature and
the discharge is more than 8°C.
CHECK ITEMS
Is there any gas leakage at flare nut connections?
Has the heat insulation been carried out at flare nut
connection?
Is the connecting cable being fixed to terminal board firmly?
Is the connecting cable being clamped firmly?
Is the drainage OK?
(Refer to “Check the drainage” section)
Is the earth wire connection properly done?
Is the indoor unit properly hooked to the installation plate?
Is the power supplyvoltage complied with rated value?
Is there any abnormal sound?
Is the cooling operation normal?
Is the thermostat operation normal?
Is the remote control’s LCD operation normal?
Is the super alleru-buster filter is installed?
 1. Please carry out insulation at pipe connection portion as mentioned in Indoor/Outdoor Unit Installation Diagram. Please wrap
the insulated piping end to prevent water from going inside the piping.
 2. If drain hose or connecting piping is in the room (where dew may form), please increase the insulation by using POLY-E FOAM
with thickness 6 mm or above.
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							11 3-way Valve
3-way Valve (Liquid Side)3-way Valve (Gas Side)
WorksShaft PositionService PortShaft PositionService Port
ShippingClosedClosedClosedClosed
(With valve cap)(With cap)(With valve cap)(With cap)
Air purgingClosedOpenClosedOpen
(Installation and(Clockwise)(Connected manifo ld(Clockwise)(Push-pin)
Re-installation)gauge w/charging cylinder)
OperationOpenClosedOpenClosed
(With valve cap)(With cap)(With valve cap)(With cap)
Pumping downClosedClosedOpenOpen
(Transferring)(Clockwise)(With cap)(Counter-clockwise)(Connected manifo ld
gauge)
EvacuationOpenOpenOpenOpen
(Servicing)(Counter-clockwise)(Connected manifo ld
gauge)(Counter-clockwise)(Connected manifo ld
gauge)
Gas chargingOpenOpenOpenOpen
(Servicing)(Counter-clockwise)(Connected manifo ld
gauge)(Counter-clockwise)(Connected manifo ld
gauge)
Pressure checkOpenOpenOpenOpen
(Servicing)(Counter-clockwise)(With cap)(Counter-clockwise)(Connected manifo ld
gauge)
Gas releasingOpenOpenOpenOpen
(Servicing)(Counter-clockwise)(Connected manifo ld
gauge)(Counter-clockwise)(Connected manifo ld
gauge)
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CS-C9DKZW CU-2C18DKH / CS-C9DKZW CU-3C20DKH 
						

							11.1. Air purging
Required tools: Hexagonal wrench, adjustable wrench,
torque wrenches, wrench to hold the
joints, gas leak detector, and charging
set.
 1. Recheck the piping connections.
 2. Open thevalve of the lowpressure side of Manifold
gauge counter-clockwise for 10 seconds, and then
close it.
 3. Check for gas leakage.
 • Check the flare connections for gas leakage.
 4. Purge the air from the system.
 • Open the Low pressure side valve of the manifold
gauge.
 • Press the valve core pin with the hexaganol wrench to
purge the air for three seconds and then wait for one
minute.
Repeat this three times or more.
 5. Balance the refrigerant in the pipings and the indoor
unit.
 • Close the Low pressure side valve of the manifold
gauge.
 • Press the valve core pin with the hexaganol wrench to
release the refrigerant until the gauge indicates.The air in the indoor unit and in the piping must be purged. If air
remains in the refrigeration pipes, it will affect the compressor,
reduce the cooling capacity, and could lead to a malfunction.
 6. Use torque wrench CWHAD-9211 to tighten the service port
nut to a torque of 1.8 kg.cm.
 7. Set both the 3-wayvalves to theopen position.
 8. Mount thevalve stemnuts to the3-wayvalves.
 9. Check for gas leakage.
 • At this time, especially check for gas leakage from both
the 3-wayvalve’s stem nuts, and from the service port
caps.
CautionIf gas leakage is discovered in step 3 above, take the
following procedures:
 1. Re-tighten the connecting portion with torque
wrenches.
If the leakage ceases, continue the works from
step 4.
 2. Locate and repair the leak. (Gas leak detector)
Repeat the works from step 1.
Service port cap
Be sure, using a torque wrench to tighten the service port nut (after using the service port), so that it prevents the gas leakage from the
refrigeration cycle.
Procedure:
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							11.2. Pumping down
 1. Confirm that both the 3-wayvalves are setto the open
position.
 • Remove the valve stem caps and confirm that the valve
stems are in the raised 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 serviceport of the3-wayvalves.
 • Connect the charge hose with the push pin to the gas
side 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 Liquid side 3-wayvalve to theclosed position. 6. Operate the air conditioner at the cooling cycle and
stop it when the gauge indicates 0 kg/cm2G.
 • If the unit cannot be operated at the cooling (weather is
rather cool), press the Pump Down switch on the Indoor
unit.
 • 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 1 to
3 kg/cm
2G.
 8. Disconnect the charge set, and mount both the 3-way
valve’s stemnuts and the service port caps.
 • Use torque wrench CWHAD-9211 to tighten the service
port nut to a torque of 1.8 N.m.
 • Be sure to check for gas leakage.
Procedure:
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							(Re-installation)
 1. Remove the capnut from3-wayvalves.
 • Remove the cap nutfrom 3-wayvalves after carefully
checked whether the piping connection was properly
and certainly done.
 2. Confirm that thevalve inboth3-wayvalves are set to
the CLOSED position.
 3. Connect the gas cylinder to the liquid-side (high-
pressure) 3-wayvalve andthe charge set to the gas
side (low-pressure) 3-wayvalve.
 • Remove the flare nut from the service port to connect
the charge set and gas cylinder.
 • Close the valves on the gas cylinder and charge set.
 4. Air purging.
 • Open the valve on the gas cylinder.
 • Open the valve on the charge set, discharge for three
seconds and wait for one minute. Repeat this three
times. 5. Check for gas leakage.
 • Check the flare connections for gas leakage.
 6. Discharge the refrigerant.
 • Close the valve on the gas cylinder and discharge the
refrigerant until the gauge indicates 3 to 5 kg/cm
2G.
 7. Disconnect the charge set and the gas cylinder.
 8. Mount thevalve stemcap nuts and the flare nuts for
service port ontothe 3-wayvalves.
 9. Mount the cap nut and service port nut onto the 3-way
valves.
 • Be sure to use a torque wrench (CWHAD-9211) to
tighten the service port nut.
 • Be sure to check for gas leakage.
11.2.1. Re-air purging
Procedure:
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CS-C9DKZW CU-2C18DKH / CS-C9DKZW CU-3C20DKH