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© 2009 Viking Preferred Service
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RTD Sensor
Cavity Lights
RTD Sensor
The oven utilizes an RTD (Resistance Temperature
Detectors) to measure the temperature in the
oven cavity. As the temperatures rise and fall, the
resistance in the RTD changes. These changes are
interpreted by the Main Control, thus controlling
the bake and broil burners. As the temperature
rises, the resistance increases. Page 18 shows the
ratio of temperature to resistance.
To access the RTD sensor, locate the sensor at the
upper rear wall of oven cavity. Remove securing
screws and gently pull the sensor forward. The RTD
has a Molex connector that once disconnected
allows testing of the sensor. With the sensor
disconnected and Volt-Ohm Meter set to Ohms,
record the sensor resistance. At room temperature
the resistance should be approximately 1050 ohms.
If the resistance reading is zero ohms or extremely
high, replace the RTD. If the readings are within
range, ohm each wire to ground. If resistance is
present, then the RTD is grounded and the physical
wires must be checked for a grounded connection.
If the RTD resistance is within range and the wires
are not grounded, the RTD is functional and should
not be replaced.
Note:
When reinstalling the sensor, make sure
the wire is pushed completely through insulation
blanket. Failure to get the wires through the
insulation blanket can overheat the wires resulting
in defective wires.
Cavity Lights
The oven utilizes 120 volt Halogen bulbs to
illuminate the oven cavity. The lights are switched
on by depressing the oven light switch on the
control panel.
To access the cavity lights, locate in the oven cavity.
Remove the screws securing the lens. Remove the
bulb from the socket once cool. With Volt-Ohm
Meter set to Ohms, measure the resistance across
the socket terminals (white/red to white/blue). If
resistance is found, the socket and wiring is good
and the bulb should be replaced. If no resistance
is found, check the wiring for a short or break. If
wiring is good, the problem lies in the socket.
Service Diagnostics and Procedures
