Daikin FTX50K(M/2)V1B - Part 7 - Trial Operation and Field Settings

Check SiBE041525F
79 Service Diagnosis
5. Check
5.1 Thermistor Resistance Check
Check No.01 Disconnect the connectors of the thermistors from the PCB, and measure the resistance of
each thermistor using a multimeter.
 When the room temperature thermistor is soldered on a PCB, remove the PCB from the
control PCB to measure the resistance.
 When the connector of indoor heat exchanger thermistor is soldered on a PCB, remove the
thermistor and measure the resistance.
The data is for reference purpose only.
Thermistor temperature (°C)
Resistance (k)
Room temperature thermistor Other thermistors
–20 73.4 197.8
–15 57.0 148.2
–10 44.7 112.1
–5 35.3 85.60
0 28.2 65.93
5 22.6 51.14
10 18.3 39.99
15 14.8 31.52
20 12.1 25.02
25 10.0 20.00
30 8.2 16.10
35 6.9 13.04
40 5.8 10.62
45 4.9 8.707
50 4.1 7.176
(R25°C = 10 k, B = 3435 K) (R25°C = 20 k, B = 3950 K)
Room temperature thermistor
(˚C)
50
25
0
–15
0
15 30
45
(kΩ)
(R11952)
Other thermistors
(˚C)
(kΩ)
–15
0
15 30
45
150
100
50
Multimeter
Resistance range
(R19751)
Multimeter
(R20505)
Room temperature
thermistor