Temperature Control Operation - Viking FDBB5361 Service Manual

Operation

Temperature Control Operation

For any temperature setting, outputs will be turned off/on based on cut-in/cut-out temperature determined
by resistance levels of freezer or refrigerator thermistors.
Refrigerator and Freezer Thermistor (NTC)
As temperature decreases, resistance increases. As temperature increases, resistance decreases.
Note: Open thermistor or thermistor circuit or a shorted thermistor will result in refrigerator continuing
to cool with error code displayed. The affected section will call for cooling 100 percent of time except
during defrost cycle
Deg F Deg C
-24 -31
-22 -30
-20 -29
-18 -28
-16 -27
-15 -26
-13 -25
-11 -24
-9 -23
-8 -22
-6 -21
-4 -20
-2 -19
0 -18
1 -17
3 -16
5 -15
7 -14
9 -13
Freezer temperature setting and thermistor value will determine if compressor/condenser fan and evaporator fan
relays (HV board) are open or closed. Compressor/ condenser fan relay must be open for 6 minutes before relay
can close again (compressor dwell time). Refrigerator temperature setting and thermistor value will determine if
fresh food fan relay is open or closed. Cut-out and cut-in temperature values must be reached and maintained for 15
seconds before output state will change (digital delay). Refrigerator and freezer control calibration can be adjusted in
Program Mode A.
12
K-Ohms Deg F
565 10
531 12
499 14
469 16
441 18
415 19
391 21
368 23
347 25
327 27
308 28
291 30
274 32
259 34
245 36
231 37
218 39
206 41
195 43
Deg C K-Ohms
-12 185
-11 175
-10 165
-9 157
-8 148
-7 141
-6 133
-5 126
-4 120
-3 114
-2 108
-1 103
0 97
1 93
2 88
3 84
4 80
5 76
6 72
Deg F Deg C K-Ohms
45 7
46 8
48 9
50 10
52 11
54 12
55 13
57 14
59 15
61 16
63 17
64 18
66 19
68 20
70 21
72 22
73 23
75 24
77 25
©2012 Viking Preferred Service
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