High Limit Switch; Cooling Fan Limit Switch; Selector Switch; Oven Thermostat - Viking VDSC305 Service Manual

VDSC COMPONENTS ( Con't )

HIGH LIMIT SWITCH

Function: The Switch has a ½ " bi-metal
disc. The two metals have different thermal
coefficients of expansion which cause the
disc to bow as it heats up. When it reaches
the calibration temperature the disc snaps
open, which opens the electrical contacts.
The Switch opens when temperature reaches
275* F plus or minus 9*F and will close
when temperatures are 248* F plus or minus
9*F.

COOLING FAN LIMIT SWITCH

Function: The Switch has a ½ " bi-metal disc.
The two metals have different thermal
coefficients of expansion which cause the disc
to bow as it heats up. When it reaches the
calibration temperature the disc snaps closed,
which closes the electrical contacts. The
Switch closes when temperatures reach 230*
F plus or minus 9* F and will open when
temperatures are below 203* F plus or minus
9*F.

SELECTOR SWITCH

Function: Rotating the shaft twists a cam
which moves one or more spring loaded
levers, which make contact with a terminal
closing the circuit.

OVEN THERMOSTAT

Function: As the shaft is rotated from the
OFF position clockwise, an internal cam
pushes a lever, which increases the
temperature at which the thermostat cycles.
Rotating the shaft 212* (angle *) switches an
external (clean) Micro Switch to the closed
position.
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