Check; Thermistor Resistance Check - Daikin FTXN09KEVJU Service Manual

Check

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 tester.
The relationship between normal temperature and resistance is shown in the table and the graph
below.
Thermistor temperature (°C / °F)
–20 / –4
–15 / 5
–10 / 14
–5 / 23
0 / 32
5 / 41
10 / 50
15 / 59
20 / 68
25 / 77
30 / 86
35 / 95
40 / 104
45 / 113
50 / 122

116
Room temperature thermistor
for 09/12 class model
(kΩ)
50
25
0
–15 0 15
5 32 59
For the models in which the thermistor is directly mounted on the PCB, disconnect the
connector for the PCB and measure.
Resistance (k)
Room temperature thermistor for
09/12 class model
73.4
57.0
44.7
35.3
28.2
22.6
18.3
14.8
12.1
10.0
8.2
6.9
5.8
4.9
4.1
(R25°C (77°F) = 10 k,
B = 3435 K)
(kΩ)
45
30 (˚C)
113 (˚F)
86 5
RTH1
Tester
(R3460)
Other thermistors
211.0
150.0
116.5
88.0
67.2
51.9
40.0
31.8
25.0
20.0
16.0
13.0
10.6
8.7
7.2
(R25°C (77°F) = 20 k,
Other thermistors
(˚C)
(˚F)
32 59 86 113
Tester
Resistance range
(R11906)
SiUS041111
B = 3950 K)
(11906)
Service Diagnosis