Sharp AY-XPC18LR Service Manual page 25

Figure 1 Temperature properties of indoor thermistors
k
100
80
60
40
20
0
Figure 2 Temperature properties of outdoor thermistors
TH1 compressor thermistor
500K
400K
300K
200K
100K
0
-20
Compressor thermistor
Heat exchanger pipe thermistor
Outdoor temp. thermistor
Suction temp. thermistor
Thermistor
Room temperature
Pipe temperature
Valve temperature
To measure the resistance, first remove
the soldering as shown at right.
Heat exchange thermistor
TH2 (Orange), TH3 (Black)
25ºC resistance 4.431 k
Room temperature
thermistor TH1 (Yellow)
25ºC resistance 10 k
-10 0 10 20
Connector
(CN8A)
25ºC resistance
45 K
5.78K 3.06K
4.17K 2.28K
1.72K
0 20 60 80 100 120
Temperature (ºC)
Thermistor No. Connector
TH1
TH2
TH3
TH4
Room temperature
Signal Color
thermistor TH1 ( 3 - 4 )
TH1
Yellow
Pipe temperature
TH2
Orange
thermistor TH2 ( 1 - 2 )
TH3
Black
Valve temperature
thermistor TH3 ( 5 - 6 )
CN2
6
1
Tester
30 40
TH2 Heat exchange thermistor
TH3 Outdoor temp. thermistor
TH4 Suction pipe thermistor
40K
0 º C resistance
14.5 K
30K
1 8
20K
10K
Tester
0
-20 0
Temperature ( º C)
Color
To measure the resistance, first remove the
connector from the board.
No. 1 to 2 Red
No. 3 to 4 Orange
No. 5 to 6 Green
No. 7 to 8 Black
3 – 6
Connector
CN8A
1
25 º C resistance
4.431 K
TH2, TH3, TH4
Tester
20 40 60
AYXPC18LR
8