Panasonic Cs C9dkzw Cu 2c18dkh Cu 3c20dkh Repair Manual

							(Gas leakage)
 1. Confirm that both the 3-wayvalves are setto the open
position.
 2. Connect the charge set tothe Gas side3-way valve’s
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(Lo side) on the charge set and
discharge the refrigerant until the gauge indicates 0
kg/cm
2G.
 • If there is no air the refrigeration cycle [the pressure
when the air conditioner is not running is higher than 1
kg/cm
2G], discharge the refrigerant until the gauge
indicates 0.5 to 1 kg/cm2G. If this is the case, it will not
be necessary to apply an evacuation.
 • Discharge the refrigerant gradually; if it is discharged
too suddenly, the refrigeration oil will also be
discharged.
11.2.2. Balance refrigerant of the 3-way valves
Procedure:
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							(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 -76
cmHg [vacuum of 4 mmHg or less].
 3. Close thevalve (Loside) on the charge 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.
11.3. Evacuation
Procedure:
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							(After Evacuation)
 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.
 • If you are using a gas cylinder, also use a scale and
reverse the cylinder so that the system can be charged
with liquid.
 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). The procedure is the
same if using a gas cylinder.
 3. Open thevalve (Loside) on the charge 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) 4. Immediately disconnect the charge hose from both the
3-way valve’sservice ports.
 • 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 stemnuts and the service port caps.
 • Use a 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.
11.4. Gas charging
Procedure:
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							 • Electronic Controller and Display Complete unit can be
seen by following the below removal procedures
Fig. 1
 − Remove the 2 caps and 2 screws at the bottom of the
Front Grille. (Fig. 1)
Fig. 2
 − Remove the Front Grille Complete. (Fig. 2)
Fig. 3
 − Release the taps on top and on the right side of metal
plate cover. (Fig. 3)
 − Then remove the metal plate cover. (Fig. 3)
 − Remove the indicator complete screw, and then remove
the indicator complete. (Fig. 3)
12 Servicing Information
12.1. Distinction of Lead Free (PbF) Printed Circuit Board
Printed circuit boards (manufactured) using lead free solder will have a PbF stamp on the Printed Circuit board.
CAUTION
 • Pb free solder has a higher melting pointthan standard solder;typically themelting point is 50 - 70°F (30 - 40°C) higher.
Please use a high temperature solder iron and set it to 700 ± 20°F (370 ± 10°C).
 • Pb free solder will tend to splash when heated too high (about 1100° F/600°C).
 • If you must use Pb solder, please completely remove all of the Pb free solder on the pin or solder area before applying Pb
solder. If this is not pratical, be sure to heat the Pb free solder until it melts, before applying Pb solder.
12.2. Indoor Electronic Controllers Removal Procedures
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							Fig. 4
 − To remove the electronic controller.
 − Remove the particular piece (Fig. 4)
 − Release CN-FM connector (Fig. 4)
 − Release CN-Sonic connector (Fig. 4)
 − Release CN-FB connector (Fig. 4)
 − Release CN-ION connector (Fig. 4)
 • Remove Control Board cover
Fig. 6
 − Remove the screw on the left side of the unit. (Fig. 6)
 − Pull the hook to the left and lift up the evaporator. (Fig.
6)
 − Pull down the Discharge Grille Complete. (Fig. 6) − Release CN-TH connector (Fig. 4)
 − Release CN-STM connector (Fig. 4)
 − Release CN-REC/DISP connector (Fig. 4)
Fig. 5
 − Press the hook to the right then take out the PCB(Fig. 5)
 − Remove Ry-Pwrconnector (black and brown) and Ac-
Wht connector from the PCB. (Fig. 5)
Fig. 7
Fig. 8
 − Remove indoor pipe sensor and air intake sensor from
the evaporator. (Fig. 7)
12.3. Indoor Fan Motor and Cross Flow Fan Removal Procedures
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							 − Remove the earth wire from the evaporator (Fig. 7)
 − Release the generator complete wire (green and red).
(Fig. 8)
 − Remove 2 screws on the right and 1 screw at the left
side of the control board. (Fig. 7)
 − Press down the hook on the left side of control board.
(Fig. 7)
 − Then pull out the Control Board Complete from the unit.
(Fig. 7)
Fig. 9
 − Remove the cross flowfan bushing from the chassis.
(Fig. 9)
 − Loosen the fan boss screw at the cross flow fan. (Fig. 9)
Fig. 10
 − Push up the evaporator andremove crossflow fan by
pulling both cross flow fan and fan motor. (Fig. 10)
12.4. Auto OFF/ON Button
 • The “Auto OFF/ON Button” (behind the front grille) is used to operate the air conditioner if remote control is misplaced or
malfunctioning.
 • Forced cooling operation is possible by pressing the “Auto OFF/ON Button” for more than 5s where “beep” sound is heard then
release the button.
 • User able to select remote control transmission code and toggle remote control signal receiving sound under various setting
mode.
 • To enter various setting mode:
 − Press the “Auto OFF/ON Button” continuosly for 5s (beep sound is heard) and release.
 − Within 20s, press the “Auto OFF/ON Button” continuously for 5s again (2 beep sound is heard) and release.
 − Various setting mode has limit up to 20s. Then return to normal operation.
12.4.1. Toggle Remote Control Signal Receiving Sound
 • Under various setting mode, press the “Auto OFF/ON Button” to toggle the remote control sound.
 − Short “beep” : Turn ON remote control signal receiving sound.
 − Long “beep” : Turn OFF remote control signal receiving sound.
 • After “Auto OFF/ON Button” is pressed, the 20s counter for various setting mode is restarted.
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							 • When the batteries are inserted for the first time or the
batteries are replaced, you may notice the indications at
remote control’s display screen blink continuosly and not
functionable. If this condition happens, try to reset the
remote control by pushing the reset terminal with a pointing
device.
 • You may also do the reset to erase the setting at remote
control and restore back the default setting.
12.4.2. Remote Control Transmission Code
 • There are 4 type ofremote control transmission code could be selected and stored in EEPROM of indoor unit. The indoor unit
will only operate when received signal with same transmissioncode from remote control. This could prevent signal inteference
when there are 2 or more indoor unit installed nearby together.
 • To change remote control transmission code, short or open jumpers at the remote control printed circuit board.
 • Under various setting mode, after select the transmission code combination of remote control, press any button of remote
control to transmit a signal to indoor unit. The transmission code will be stored in EEPROM.
 • After signal is received, the various setting mode is cancelled and return to normal operation.
12.5. Remote Control Reset
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							13.1. Refrigeration cycle system
In order to diagnose malfunctions, make sure that there are no
electrical problems before inspecting the refrigeration cycle.
Such problems include insufficient insulation, problem with the
power source, malfunction of a compressor and a fan.
The normal outlet air temperature and pressure of the
refrigeration cycle depends on various conditions, the standard
values for them are shown in the table to the right.
13 Troubleshooting Guide
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							13.2. Relationship between the condition of the air conditioner and
pressure and electric current
Cooling Mode
Condition of the air
conditionerLow PressureHigh PressureElectric current during operation
Insufficient refrigerant (gas
leakage)
Clogged capillary tube or
Strainer
Short circuit in the indoor unit
Heat radiation deficiency of
the outdoor unit
Inefficient compression
 • Carry out the measurements of pressure, electric current, and temperature fifteen minutes after an operation is started.
13.3. Diagnosis methods of a malfunction of a compressor
Nature of faultSymptom
 • Electric current during operation becomes approximately 20% lower than the normal value.
Insufficient compressing of a compressor • The discharge tube of the compressor becomes abnormallyhot (normally 70 to 90°C).
 • The difference between high pressure and low pressure becomes almost zero.
 • Electric current reaches a high level abnormally, and the value exceeds the limit of an
ammeter. In some cases, a breaker turns off.
Locked compressor
 • The compressor has a humming sound.
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							14 Technical Data
14.1. Thermostat characteristics
14.2. Operation characteristics
14.2.1. CS-C9DKZW CU-2C18DKH
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