Shorted Thermistor Alarm; Power Loss Alarm; Door Open Alarm - Viking FDSB5481 Service Manual

3. Shorted Thermistor Alarm

The controller will sense a shorted thermistor
condition within 15 seconds of power on.
Shorted Refrigerator Thermistor Alarm
When the control senses that the refrigerator
thermistor is shorted, "Shr" is displayed on the
control along with the zone, "REFRIGERATOR".
If the control was in the Freezer zone when the
condition occurred, it automatically switches over
to the faulty zone ("REFRIGERATOR"). You also
receive an audible alarm consisting of five beeps
that occurs only one time. The visual alarms as
described above will continue until the condition
is corrected.
Shorted Freezer Thermistor Alarm
When the control senses that the freezer thermistor
is shorted, "Shr" is displayed on the control along
with the zone, "FREEZER". If the control was in
the Refrigerator zone when the condition occurred,
it automatically switches over to the faulty zone
("FREEZER"). You also receive an audible alarm
consisting of five beeps that occurs only one time.
The visual alarms as described above will continue
until the condition is corrected.
The unit will continue to execute temperature control
and defrost operations as required until the condition
is corrected. The control does this through software
programming, acting as if the cut-out temperature
is never reached in the faulty zone, temperature
control in the other zone is unaffected.
The visual alarms will reset by themselves within
15 seconds of the open thermistor condition being
corrected and temperature control reverts back to
normal operation.
©2012 Viking Preferred Service
Service Procedures

4. Power Loss Alarm

If the control experiences a power loss condition
and power is restored, the Power Loss alarm is
displayed. This consists of the "POWER" indicator
being flashed on and off along with the temperature
digits flashing on and off. All other indicators will be
off and only "ACTIVATE CONTROLS and ALARM
OFF keys are active on the control panel.
There is no audible alarm indication associated
with the power loss alarm. Pressing and releasing
the "ALARM OFF" pad will result in "POWER"
indicator extinguishing and the temperature digits
revert back to normal temperature display.

5. Door Open Alarm

If the control senses that a door is open for a period
of time, equal to the door open delay (factory default
is 3 minutes, this time can be adjusted in service
mode B) a continuous audible alarm will sound.
At the same time "DOOR OPEN" illuminates on
LED display and will remain on until condition is
corrected.
Press the "ALARM OFF" pad and the audible alarm
will cease. Pressing and holding the "ALARM OFF"
pad for three seconds will disable the audible door
alarm, until the "ALARM OFF" pad is again held for
three seconds which will enable the audible door
alarm once again.
These actions will not clear the visual "DOOR"
alarm, that can only be cleared by shutting the
doors and allowing the control to reset it.
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