Panasonic U-8MF2E8 Service Manual page 135

4. 3WAY Alarm Codes
F08 Alarm
Alarm code F08
Alarm meaning Outdoor air temperature sensor trouble
Alarm conditions (1) A/D step is 10 steps or less (short circuit).
(2) A/D step is 1014 steps or more (open circuit)
Probable cause (1) Sensor malfunction (including connector)
(2) PCB malfunction
Check (1) Measure the sensor resistance. Check that the sensor is operating normally.
(2) Use a remote controller monitor or PC monitor to check the temperature that is recognized by
the microcomputer.
Correction —
Example —
Notes —
F12 Alarm
Alarm code F12
Alarm meaning Compressor intake temperature sensor trouble (SCT)
Alarm conditions (1) A/D step is 10 steps or less (short circuit).
(2) A/D step is 1014 steps or more (open circuit)
Probable cause (1) Sensor malfunction (including connector)
(2) PCB malfunction
Check (1) Measure the sensor resistance. Check that the sensor is operating normally.
(2) Use a remote controller monitor or PC monitor to check the temperature that is recognized by
the microcomputer.
Correction —
Example —
Notes —
F14 Alarm
Alarm code F14
Alarm meaning SCG temperature sensor trouble
Alarm conditions (1) A/D step is 10 steps or less (short circuit).
(2) A/D step is 1014 steps or more (open circuit)
Probable cause (1) Sensor malfunction (including connector)
(2) PCB malfunction
Check (1) Measure the sensor resistance. Check that the sensor is operating normally.
(2) Use a remote controller monitor or PC monitor to check the temperature that is recognized by
the microcomputer.
Correction —
Example —
Notes —
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3WAY SYSTEM
Trouble Diagnosis
5