Temperature Control Operation - Viking VCSB5481 Series Technical Information

Alarms
Power Loss Alarm
After power isinitially applied to the unit, ifa power loss isexperienced, the temperature (7segment display characters) and the
"POWER" indicator on the LED display will flash (1 sec. on and 1 sec. off). All other indicators will be off.
Press andrelease the"ALARM OFF" pad, this will turn the "POWER" indicator offand thecurrent temperature will bedisplayed.
Door Open Alarm
Jf the control senses that a door is open for a period of time equal to the DOOR OPEN DELAY (factory set to 3 min
utes), the controller invokes an alarm tone that beeps continuously with a pattern of 330ms on, 250ms off, 300 ms
on, 1250ms off, and "DOOR" indicator illuminates.
1. Turn off Door Open audible alarm by pressing Alarm Off pad or by closing door
2. Deactivate Door Open audible alarm by pressing Activate Controls pad and then press and hold Alarm Off pad
for 3 seconds.
3. Door alarm delay can be adjusted in Program Mode B.
High Temperature Alarm
When the controller detects critical temperature in either the refrigerator (above 50 deg F) or freezer (above 15deg F ) for a du
ration of 2 hours, an Alarm will sound ( 1sec. on and 1 sec. off continuously ). The "HIGFI TEMP" indicator on LED will come
on and "REFRIGERATOR" or "FREF2ZER" indicator on LED will flash (1 sec. on and 1sec. off) to accompany the audible alarm.
1. Alarm tone stops if temperature(s) falls below levels indicated above.
2. The indicators will continue to display as described above until "ALARM OFF" pad is pressed and released.
Thermistor Alarm
When the controller detects an open thermistor, five beeps (300 ms on, 300 ms off) will occur, the LED will display "oPn" in the
temperature area and the applicable "REFRIGERATOR" or "FREEZER" indicator will illuminate, indicating the faulty thermistor
location.
When the controller detects a shorted thermistor, five beeps (300 ms on, 300 ms off) will occur, the LED will display "Shr" in the
temperaturearea and the applicable "REFRIGERATOR" or "FREEZER" indicator will illuminate, indicating the faulty thermistor
location.
Thecontroller will still maintain temperature control and defrost operations in both sections of the unit until repair is accom
plished, regardless of whether the thermistor is open or shorted. In the section where faulty thermistor is located, unit will be
operated as if the cut-out temperature is never reached, while the other section will be unaffected and operate normally.
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 and refrigerator thermistors.
Refrigerator and Freezer Thermistor (NTC)
Astemperature decreases.resistance increases.
As temperature increases,resistance decreases.
NOTE: Openor shorted thermistor will result in unitcontinuing to cool, thesection containing the faulty thermistor will never
obtaincutout and will continue to try and reach it, this could result in freezing up if not repaired in a timely manner.