Panasonic CS-F24DD2E5 / CS-F28DD2E5 / CS-F34DD2E5 / CS-F43DD2E5 / CS-F50DD2E5 / CU-L24DBE5 / CU-L28DBE5 / CU-L34DBE5 / CU-L43DBE5 / CU-L50DBE8 Service Manual ▷ View online
• Press the timer set button while the error is displayed.
The F15-44 display will change to the detail display.
• How to display the past error message
If the CHECK display on the wired remote control is not flashing, press the CHECK button continuously for 5 seconds or more
to display the past problem details.
to display the past problem details.
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12.8. Emergency operation
When using the wireless remote control and losing the remote controller, emergency operation can be operated by pressing the
auto button in the receiver.
auto button in the receiver.
• Press the auto button continuously within 5 seconds
→ emergency operation
If there is an abnormality in the temperature thermistor (disconnect or shorted), indoor unit cannot be operated.
If abnormality detected in the indoor or outdoor unit, turn off the main power supply and find the cause.
Check the resistance of each thermistor of both indoor and outdoor units by refering the resistance table as follows.
Thermistor resistance table
Resistance value (k
Ω)±5%
Temperature
Indoor
Outdoor
Room
temperature
thermistor
Pipe
temperature
thermistor
Outdoor
temperature
thermistor
Discharge
temperature
thermistor
Suction
temperature
thermistor
Pipe
temperature
thermistor
Defrost
temperature
thermistor
-20°C
158.5
211.3
158.5
528.3
47.9
47.9
47.9
-10
87.5
116.7
87.5
291.8
27.1
27.1
27.1
-5
66.1
88.2
66.1
220.5
20.7
20.7
20.7
0
50.5
67.3
50.5
168.3
15.9
15.9
15.9
5
38.9
51.9
38.9
129.8
12.4
12.4
12.4
10
30.3
40.4
30.3
100.9
9.8
9.8
9.8
15
23.8
31.7
23.8
79.2
7.7
7.7
7.7
20
18.8
25.1
18.8
62.7
6.2
6.2
6.2
25
15
20
15
50
5
5
5
30
12.1
16.1
12.1
40.2
4
4
4
40
8
10.6
8
26.5
2.7
2.7
2.7
50
5.4
7.2
5.4
17.9
1.9
1.9
1.9
60
3.7
5
3.7
12.4
-
1.3
-
70
-
3.5
-
8.8
-
0.9
-
80
-
2.5
-
6.3
-
-
-
90
-
1.9
-
4.7
-
-
-
100
-
1.4
-
3.5
-
-
-
During outdoor unit emergency operation or test operation, the LED on the P.C.B. will flash.
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12.9. Self-diagnosis
• The display screen on the wired remote control unit and the self-diagnosis LEDs (green) on the outdoor unit printed circuit board
in the outdoor unit can be used to indicate where the location of a problem is.
Refer to the table below to remove the cause of the problem, and then re-start the air conditioner system.
• If the problem disappears and operation returns to normal, the CHECK display on the remote control unit will switch off, but the
self-diagnosis LED will remain illuminated until operation is resumed.
• Key indicator
LED Symbol
Description
Off
Flashing
Illuminated
Wired remote
control unit display
Outdoor unit printed circuit board LED
Location of problem
Check location
Abnormal
display
Detail
display
302 303 304 305 306 307 308 309
F15
-01
Drain level Float switch problem Drain pump and drain pipe, indoor unit
connectors CN-DRMTR&CN-TH2
F16
-01
Louver switch problem
Louver motor, decorative panel
connection terminal, or indoor unit louver
motor connectors
connection terminal, or indoor unit louver
motor connectors
F17
-02
D. C Fan Motor problem
Indoor unit D. C Fan motor or connection
terminals
terminals
F20
-01
Indoor temperature sensor
problem
problem
Indoor temperature sensor lead wire or
indoor unit connector or CN-TH2
indoor unit connector or CN-TH2
-02
Remote control thermistor
problem
problem
Remote control thermistor
F21
-01
Pipe temp. sensor problem
(indoor unit)
(indoor unit)
Pipe temperature sensor lead wire or
indoor unit connector CN-TH1
indoor unit connector CN-TH1
F26
-01
Remote control transmission
problem
problem
Remote control unit cable and connection
terminals
terminals
F27
-01
Indoor/outdoor unit
disconnection problem
disconnection problem
Indoor/outdoor unit connection cable and
connection terminals, or indoor unit and
outdoor unit power supplies (indoor side)
connection terminals, or indoor unit and
outdoor unit power supplies (indoor side)
-05
Indoor/outdoor unit connection
problem
problem
Indoor/outdoor unit connection wire
(indoor side)
(indoor side)
F27
-01
Indoor/outdoor unit
disconnection problem
disconnection problem
Indoor/outdoor unit connection cable and
connection terminals, or indoor unit and
outdoor unit power supplies (outdoor side)
connection terminals, or indoor unit and
outdoor unit power supplies (outdoor side)
-05
Indoor/outdoor unit connection
error problem
error problem
Indoor/outdoor unit connection wire
(outdoor side)
(outdoor side)
F30
-01
System problem
Total capacity for the number of indoor
units is insufficient, or over check the total
capacity and the number of indoor units
units is insufficient, or over check the total
capacity and the number of indoor units
-02
Open phase, or reversed phase
of supply
of supply
Check the main power supply terminal
board connections, or switch over any two
of the power supply wires.
board connections, or switch over any two
of the power supply wires.
F31
-01
Suction pressure protection
Insufficient refrigerant
-02
High-pressure cut-off
Check the Refrigeration system
-06
4 way valve problem
Check the 4 way valve or lead wire
-08
Freezing problem (Cooling
model)
model)
Check the Refrigerant system
-09
Leakage Refrigerant problem
Check the Refrigerant system
-10
Refrigerant system problem
Insufficient refrigerant or valve operation
(closed)
(closed)
F32
-03
Inverter protection (Low DC
voltage)
voltage)
Check the Power supply
-04
Inverter protection (IPM
protection)
protection)
IPM fault or PCB (MAIN) fault
-05
Compressor overcurrent
protection
protection
Open phase or lock in compressor
-06
Compressor discharge temp.
protection
protection
Insufficient refrigerant
-08
Inverter protection (PFC
protection)
protection)
PFC fault (PCB-PFC fault)
-09
Inverter protection (DC current
protection)
protection)
IPM fault or lock in compressor
-10
Number of rotation Compressor
problem
problem
IPM fault or lock in compressor
F35
-02
D. C Fan motor lock problem
D. C Fan motor lock
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Wired remote
control unit display
Outdoor unit printed circuit board LED
Location of problem
Check location
Abnormal
display
Detail
display
302 303 304 305 306 307 308 309
F40
-01
Outlet temperature sensor
problem
problem
Outlet temperature sensor lead wire,
connector CN-TH1
connector CN-TH1
-11
Compressor suction
temperature sensor problem
temperature sensor problem
Suction temperature sensor (SUC T.
TEMP) lead wire, connector CN-TH2 or
valve operation (closed)
TEMP) lead wire, connector CN-TH2 or
valve operation (closed)
-21
Heat exchanger outlet
temperature sensor problem
temperature sensor problem
Heat exchanger outlet temperature sensor
(COND TEMP) lead wire, connector CN-
TH1
(COND TEMP) lead wire, connector CN-
TH1
-31
DEF temperature sensor
problem
problem
DEF temperature sensor (PIPE TEMP)
lead wire, connector CN-TH2
lead wire, connector CN-TH2
-51
Compressor discharge
temperature sensor problem
temperature sensor problem
Compressor discharge temperature
sensor (DIS T. TEMP) lead wire,
connector CN-DIS
sensor (DIS T. TEMP) lead wire,
connector CN-DIS
F41
-02
High pressure switch open
circuit problem
circuit problem
High-pressure switch lead wire, connector
CN-PSW1
CN-PSW1
-11
Low pressure sensor problem
Low-pressure sensor lead wire, connector
F42
-11
Current detector open circuit
Outdoor unit P.C. B (NOISE FILTER) fault
or connector ACN2
or connector ACN2
F44
-01
Inverter protection (IPM temp.
sensor problem)
sensor problem)
IPM fault or PCB (MAIN) fault
LED308
LED309
Unit No. (when twin or triple)
• The LED301 (green) illuminates to indicate that the microprocessor
on the printed circuit board is operating normally.
If the LED is switched off is flashing irregularly. Check the power
supply, and turn it off and then back on again
supply, and turn it off and then back on again
Master unit problem
Slave unit problem
Example self-diagnosis LED location for CU-L50DBE8.
Note : This PCB is for explanation purpose only. It may be different from actual unit.
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