Daikin BPMK928B42, Service Manual

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Si18-201 Troubleshooting - SkyAir Indoor Unit
Service Diagnosis 259
2.6.7 Malfunction of Suction Air Temperature Sensor System
Remote
Controller
Display
C9
Applicable
Models AII indoor unit models
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 short-circuited
while the unit is running.
Supposed
Causes
"
Failure of the sensor itself
"
Broken or disconnected wire
"
Failure of indoor unit PC board
"
Failure of connector contact
Troubleshooting
Note: Measure the resistance while referring to the thermistor temperature and resistance conversion table.
Thermistor temperature and resistance conversion table.
Disconnect the suction air
temperature sensor (R1T) from
X19A on the indoor unit PC
board and measure the
resistance.
Suction air temperature
sensor replacement
If contact is OK.
replace outdoor unit PC
board.
Is the thermistor
normal?
(See note)
(MF017)
NO
YES
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.
Temperature Suction, heat exchanger(indoor)
outdoor air, outdoor unit suction
pipe sensor (k
Ω
)
Temperature Suction, heat exchanger(indoor)
outdoor air, outdoor unit suction
pipe sensor (k
Ω
)
-6.0 90.8 28.0 17.6
-4.0 81.7 30.0 16.2
-2.0 73.5 32.0 14.8
0.0 66.3 34.0 13.6
2.0 59.8 36.0 12.5
4.0 54.1 38.0 11.5
6.0 48.9 40.0 10.6
8.0 44.3 42.0 9.8
10.0 40.2 44.0 9.1
12.0 36.5 46.0 8.4
14.0 33.2 48.0 7.8
16.0 30.2 50.0 7.2
18.0 27.5 52.0 6.9
20.0 25.1 54.0 6.2
22.0 23.0 56.0 5.7
24.0 21.0 58.0 5.3
26.0 19.2