Norcold EV0041 Service Manual page 14

Procedure F: Measuring Thermistor Resistance
An open thermistor will prevent the compressorfrom running.
1 . Tum off refrigerator.
2. Disconnect the thermistor assembly wire from DC power
board jumper. See Figure 19.
3. Measure thermistor resistance at connector pins as
follows.
8 lnmerse the thermistor in a bath of ice as shown in
Figure 20 to determine if the resistance values
change with temperature changes
II Cross reference thermistor resistance reading using
the Resistance Value Table to determine known
temperatures .
1/J If the thermistor resistance measures within 1.6-29
kOhm, the thermistor is good
II Replace the thermisto if the reaing is OL.
DC Power Supply
·- Connector jumper-Thermistor
; - "' " "' ' " .... b,
" " Connector jumper- Compressor
Figure 19. Thermistor connection jumper.
Thermistor Resistance Values Table.
Thermistor
Temperature
-18
-12
-7
-1
Allowable Res istance
(in kilo Ohm [kQ])
Minimum-Maximum
0
10
20
30
40
50
60
70
80
90
4 """""""""""""" """"""" "" """" ""
8.7-10.7
7.0- 8.6
5.7- 7.0
4.8- 5.7
4.0- 4.9
3.2- 4.0
2.5- 3.1
1.9- 2.3
1.7- 2.0
1.6- 1.9
10
16
21
27
32
Figure 20. Checking Thermistor resistance with ice bath.