Daikin FTKS50BVMB, Service Manual

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SiEN18-622 Troubleshooting for SkyAir Indoor Unit
Troubleshooting 345
5.10 Malfunction of Suction Air Thermistor
Remote Control
Display
C9
Applicable
Models FFQ, FCQ, FBQ, FHQ
Method of
Malfunction
Detection
Malfunction detection is carried out by temperature detected by suction air temperature sensor.
Malfunction
Decision
Conditions When the suction air temperature sensor’s thermistor becomes disconnected or shorted while
the unit is running.
Supposed
Causes „ Failure of the sensor itself
„
Broken or disconnected wire
„ Failure of indoor unit PCB
„
Failure of connector contact
Troubleshooting
Check No.02
Refer to P.351
Disconnect the sunction air
temperature sensor (R1T)
from X19A on the indoor unit
PCB and measure the
resistance.
Is the
thermistor normal?
(See note)
NO
YES
(Q0418)
NO
YES
Check contact of connector
Is it normal?
See Check No. 02 for “Thermistor temperature and resistance characteristics”.
Connect correctly.
Heat exchanger
sensor replacement.
If contact is OK,
replace outdoor unit
PCB.
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.