Panasonic Cs W18bd3n Cs W24bd3n Cs W28bd3n Series Repair Manual

							If test operation does not proceed correctly
Carry out test operation after approximately 6 hours have passed
since the power was turned on (crankcase heater is energized). If
operation is started by using the remote control within 1 minute of
turning on the power, the outdoor unit settings will not be made
correctly and correct operation will not be possible.
If the following symptoms occur after turning on the power,
check the wiring connections once more.
 
    • 
• •  • 
For standard installation
(System example)
 1. The main power is turned on while the indoor-outdoo r
transmission wires are not connected (open circuit at
section A)
Symptom:
Remote control unit . . . “CHECK” flashes
NOTE:
Indoor unit. . . LED2 on printed circuit board flashes
Outdoor unit. . . LED3 and LED7 on printed circuit
board flash
 2. The main power is turned on while the indoor-outdoo r
power supply wires are not connected (open circuit at
section B)
Symptom:
Remote control unit . . . Display of “No power supply”
NOTE:
Indoor unit...Nodisplay
Outdoor unit. . . LED3 and LED7 on printed circuit
board flash
 3. The main power is turned on while the remote control
unit connection cord is not connected (open circuit atsection C)
Symptom:
Remote control unit . . . Display of “No power supply”
NOTE:
Indoor unit . . . LED1 on printed circuit board stays
illuminated
Outdoor unit . . . LED1 on printed circuit board stays
illuminated
(When remote controldisplay shows “Power supply ”)
(When remote controldisplay shows “No power supply ”)
Remedy
 1. Turn off the main power.
↓
 2. Conne ct the disconnected wire correctly.
↓
 3. Turn the main power back on.
↓
 4. After 1 minute, start operation using the remote control.
(Indoor unit . . . Operation will start according to the
remote control setting.)
(Outdoor unit...Operation will start after 3-5 minutes.)
NOTE:
The “CHECK” display on theremote control and the
flashing of LEDs on the printed circuit boards will not occur
immediately. They will appear 3-6 minutes after the main
power is turned on.
22 TROUBLE SHOOTING
71 
						

							 1. The main power is turned on while the transmission
wires between the indoor unit(s) are not connected
(open circuit at section A)
Symptom:
Nothing abnormal appears on the remote control
display . If operation is then started in this condition, the
combination of the 43BB outdoo r unit and the 40U
indoor unit (master unit) will cause abnormal operation
to occur.
↓
If operation continues, an abnormality will occur on the
refrigeration cycle and operation will stop.
 
    − 
− −  − 
Remote control. . . “CHECK” flashes
 
    − 
− −  − 
Indoor unit (master). . . The LEDs on the printed
circuit board flash and operation stops
 
    − 
− −  − 
Indoor unit (slave) . . . LED1 on the printed circuit
board illuminates and the unit does not operate at all
 
    − 
− −  − 
Outdoor unit . . . The LEDs on the printed circuit
board flash and operation stops
 2. The main power is turned on while the power supply
wires between the indoor unit(s) are not connected
(open circuit at section B)
Symptom:
Same as above. If operation continues, an abnormality
will occur on the refrigeration cycle and operation will
stop.
↓
 
    − 
− −  − 
Remote control. . . “CHECK” flashes
 
    − 
− −  − 
Indoor unit (master). . . The LEDs on the printed
circuit board flash
 
    − 
− −  − 
Indoor unit (slave) . . . The LEDs on the printed
circuit board do not illuminate and the unit does not
operate at all
 
    − 
− −  − 
Outdoor unit . . . The LEDs on the printed circuit
board flash and operation stops 3. The main power is turned on while the remote control
connection cord is not connected (open circuit at section
C)
Symptom:
 
    − 
− −  − 
Remote control unit . . . Display of “No powersupply ”
 
    − 
− −  − 
Indoor unit (master). . . LED1 on the printed circuit
board stays illuminated and the unit does not
operate
 
    − 
− −  − 
Indoor unit (slave) . . . LED1 on the printed circuit
board stays illuminated and the unit does not
operate
 
    − 
− −  − 
Outdoor unit . . . LED1 on the printed circuit board
stays illuminated and the unit does not operate
Remedy
 1. Turn off the main power.
↓
 2. Conne ct the disconnected wires correctly.
↓
 3. Turn the main power back on.
↓
 4. After 1 minute, start operation using the remote control.
(Indoor units . . . Operation will start according to the
remote control setting.)
(Outdoor unit...Operation will start after 3-5 minutes.)
If slave units do not operate even after the wiring has been
corrected (automatic addressing is not possible)
 1. Check that DIP switches 1 to 4 and DIP switch 8 are all
set to OFF, and then stop operation.
↓
 2. Press the ADDRESS RESET button(SW3) at the
outdoo r unit for approximately 4 seconds
(The self-diagnosis LEDS 2 to 8 will illuminate in order,
and the system is reset once they are all illuminated.)
The above procedure cannot be used to carry out automatic
address resetting during group control.
72 
						

							 1. The main power is turned on while the transmission
wires between the indoor unit and the outdoor unit are
not connected (open circuit at section A).
Symptom:
Operation of indoor unit No. 1 and indoor unit No. 3 is
possible.
However, “CHECK” flashes in the remote control unit
display for 3-5 minutes after the main power is turned
on.
 
    − 
− −  − 
Remote control. . . “CHECK” flashes.
 
    − 
− −  − 
Indoor unit No. 2 . . . LED2 on the printed circuit
board flashes (both master and slave units).
 
    − 
− −  − 
Outdoor unit No. 2 . . . LED3 and LED7 on the
printed circuit board flash.
 2. The main power is turned on while the power supply
wires between the indoor units are not connected (open
circuit at section B).
Symptom:
Operation of indoor unit No. 1 and indoor unit No. 3 is
possible.
However, if operation is then started in this condition,
the combination of the 28BB outdoo r unit and the 14BB
indoor unit (master unit) will cause abnormal operation
of indoor unit No. 2 to occur.
↓
If operation continues, an abnormality will occur on the
refrigeration cycle and aoperation will stop.
 
    − 
− −  − 
Remote control . . . “CHECK” flashes (indoor unit
No. 2 abnormality).
 
    − 
− −  − 
Indoor unit No. 2 . . . LED2 on the printed circuit
board flashes (both master and slave units).
 
    − 
− −  − 
Outdoor unit No. 2 . . . The LEDs on the printed
circuit board flash.
 3. The main power is turned on while the remote control
connection cord is not connected (open circuit at section
C).Symptom:
Nothing abnormal appears on the remote control
display , and operation of indoor unit. No. 1 and indoor
unit No. 2 is possible.
However, indoor unit No. 3 cannot be operated.
Remedy
 1. Turn off the main power.
↓
 2. Conne ct the disconnected wires correctly.
↓
 3. Turn the main power back on.
↓
 4. After 1 minute, start operation using the remote control.
(Indoor units . . . Operation will start according to the
remote control setting.)
(Outdoor units...Operation will start after 3-5 minutes.)
If slave units do not operate even after the wiring has been
corrected (automatic addressing is not possible)
 1. Check that DIP switches 1 to 4 and DIP switch 8 are all
set to OFF, and then stop operation.
↓
 2. Press the “AIRSWING AUTO”, “OPERATION ” and “A/C
No.” buttons simultaneousl y.
The addresses will be momentarily reset, and then
automatic address setting will be carried out once more.
The above procedure cannot be used to carry out automatic
address resetting of twin/triple control.
(Note on automatic address setting)
The printed circuit boards automatically store the connected
system configuration when power is supplie d. As a result,
once the power has been turned on for these printed circuit
boards, the units can not be changed about within the
system, even if the units are of the same model and have
same capacity.
73 
						

							 1. Automatic address setting (no need to have dip-switch set)
If the wiring connected properly as above example, the address is set automatically by the main powersupply. An indoor unit
with remote control will be set as the master. If the power source is installe d to indoor units and outdoor separately, turn on the
switch as the following procedure: outdoo r unit, indoor unit with control, and other indoor units.
When theslave units do not operate (when address cannot be set)
Important: The address for the group control cannot be reset, using the above mentioned procedure.
 2. Manua l address setting (by dip-switchDSW1)
When you set theaddress manua lly, set the dip-switch of the PC board in the indoor unit as follow:
74 
						

							 1. Automatic address setting (no need to have dip-switch set)
If the wiring connected properly as above example, the AC numbe rs are set automatically by the main powersupply . An indoor
unit with remote control will be set as the master.
If the power source is installe d to indoor units and outdoo r separately, turn on the switch as the following procedure: outdoo r
unit, indoor unit with controller, and other indoor units. The AC numbe r will be set at random.
 2. Manua l address setting (by dip-switchDSW1)
When you set theaddress manua lly, set the dip-switch of the PC board in the indoor unit as follow:
 3. Manua l address setting (by dip-switchDSW1)
When you set theaddress manua lly, set the dip-switch of the PC board in the indoor unit as follow:
75 
						

							Procedures of deleting memory attwincontrol system
Procedure of deleting memory at group control system  1. Set the “OFF” position for main power supply switch.
 2. Set the “ON” position for No. 8 pin of dip switch (DSW1) on indoor unit P.C. board.
 3. Take main power supply switch “ON” for one minute, and then main power supply switchoff.
 4. Set the “OFF” position for No. 8 pin of dip switch (DSW1).
 1. Set the “OFF” position for main power supply switch.
 2. Set the “ON” position for No. 1 pin to No. 4 pin of dip switch (DSW1) on indoor unit P.C. board.
(No. 8 pin of dip switch (DSW1)should be “OFF” position)
 3. Take main power supply switch “ON” for one minute, and then main power supply switchoff.
 4. Set the “OFF” position for No. 1, No. 2, No. 3 and No. 4 pin of dip switch (DSW1).
(Important notice)
Above procedures are for deletin g memory on indoor unit P.C. board. And it is not for Address reset.
22.1. Indoor unit P.C. board layout.
76 
						

							Emergencyoperation
 
    • 
• •  • 
Emergency operation of outdoor unit
Emergency operation can be carried out by setting the
DSW1 switch on the printed circuit board inside the
outdoo r unit to the EMERGENCY position. However,
emergency operation is only carried out when an
abnormality is detected by the indoor/outdoor
temperature thermistors.
The resistance values of each thermistor are measured
as shown in the table below to determine if there is an
abnormality.
Thermistor resistance table
Temperatu reResistance value (kΩ
)±5%
Room temperature
thermistorPipe temperature
thermistor
-20°C205.8197.8
-10°C114.6111.9
-5°C87.385.4
0°C67.065.8
5°C51.851.0
10°C40.439.9
15°C31.730.7
20°C25.125.0
25°C20.020.0
30°C16.116.0
40°C10.410.6
50°C6.97.1
60°C4.74.9
70°C___3.5
80°C___2.5
90°C___1.8
100°C___1.4
The pipe temperature thermistor resistance value are
the same for the indoor and outdoor units.

 
    − 
− −  − 
Set only the thermistor which shows an abnormality
to the condition shown in the table below to carry out
emergency operation
ThermistorCooling modeHeating mode
Indoor unitRoom temperatureFixed at 25°C
Room temperatureShortedOpen
ThermistorCooling modeHeating mode
Outdoor unitDischarge
temperatureOpenShorted
Heat exchanger
outlet temperatureShortedOpen
 
    − 
− −  − 
Refer to the circuit diagram for the connection
locations for each thermistor.
 
    − 
− −  − 
If there is an abnormality in the roomtemperature
thermistor, the temperature will be fixed at 25°C
regardless of the remote control unitdisplay .
NOTE:
 
    − 
− −  − 
Any abnormalities detected by the temperature
thermistors are ignored during emergency operation,
so that long-term operation in this mode should be
avoided.
 
    − 
− −  − 
After emergency mode operation has been
completed and normal operation is to be resumed,
turn the power supplie s for the indoor and outdoo r
units off and return the DIP switch to the NORMAL
position.
 
    − 
− −  − 
Self-diagnosis LEDS 4 to 6 will flash during
emergency operation.
23 EMERGENCY OPERATION
77 
						

							24 CONTROL
24.1. Description of basic Functions
24.1.1. Cooling mode operation time chart
(*1)
Outdoor unit fan start control during cooling
At the start of cooling mode and drying mode operation, the outdoo r unit heat exchan ger outlet temperature is detected in order
to set the fan speed.
Operation is carried out at the fan speed detected for 30 seconds.
After 30 seconds, the heat exchan ger outlet temperature is detected and the outdoo r unit fan speed is changed automatically .
(*2)
Cooling low outdoor temperature protection
When theheat exchan ger outlet temperature drops to less than 12°C for a continuous period of 10 minutes, the outdoor unit stops
running.
This is cancelled after 3 minutes (re-start prevention)
 
    • 
• •  • 
Remote control display s and indoor unit operation continue during thistime.
 
    • 
• •  • 
The 10-minute countdown is cleared if the compressor stops or if the temperature at the outdoor unit outlet rises to 13.5°C or
higher.
78 
						

							24.2. Freezing prevention control
 1. Operation
During cooling mode operation, after 9 minutes have passed since the compressor turned on, the outdoor units stops operating
when the temperature detected by the indoor unit pipe temperature sensor is 2°C or lower.
The indoor unit continues operating at the fan speed set by the remote control unit. (The remote control unitdisplay does not
change.)
 2. Cancelling
This control is cancelled when the temperature detected by the indoor unit pipe temperature sensor is 15°C or higher.
(If the outdoor unit stops even though the temperature is 15°C or higher, restart prevention control will activated and the outdoor
unit will not start again for 3 minutes.)
(The 9-minute countdown is cleared while the compressor is stopped.)
(The above illustration shows the operation when there are no conditions for turning the outdoor unit off other than freezing
prevention.)
24.3. Heating mode operation time chart (Heat pump type only)
79 
						

							(*2)
Outdoor unit fan control during heating mode operation
Under conditions when the compressor is on during heating mode operation (except during defrosting and when the liquid bypass
valve is on), the outdoor unit fan is controlled by means of input (CN2) indicating whether the contact of the heating pressure switch
on the outdoor unit circuit board is open or closed. (At the start of heating mode operation, the fan operates at HI speed.)
24.4. Hot starting
1. When heating mode operation starts
 1. Start
Hot start control commences heating mode operation starts.
 2. Operation
“PREHEAT” appears on the remote controldisplay . (Other display s remain unchanged.)
At the indoor unit, the indoor unit fan stops. In additio n, during hot starting, the louvre stays at the horizon tal position (angle
0°).
 3. Cancelling
After 1 minute has passed since heating mode operation started, or if the compressor has turned on, hot starting is
cancelled when the temperature detected by the indoor unit pipe temperature sensor is 18°C or higher.
After cancellation, the PREH EAT display on theremote control disapp ears and the louvre operation returns to the previous
setting.
(However, for 2 minutes after cancellation, the indoor unit fan operates at LOW speed, and then returns to the previous
setting.)


80