Daikin Skyair RY71K, Service Manual

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Si-71A Troubleshooting by Remote Controller Display / LED Display
Troubleshooting 107
6.9 Malfunction of Suction Air Temperature Sensor System
Remote Controller
Display
& <
& < & <
& <
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 shorted 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)
NO
YES
(SF011)
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