Viking VGDO271, Сервисный журнал, Страница: 14 / 52

T EST PROCEDURES
To avoid the risk of electrical shock, personal injury or death, disconnect power
before servicing, unless testing requires it.
Control compartment tests generally requires removal
of oven from cabinet cutout. See disassembly
instructions to access control compartment.
Sail Switch
Sail switches are located in the rear of control
compartment and mounted to control compartment
back, in front of the fan motors. During self-clean
operations thermal switch contacts close, supplying
power to fan motors. Air from the fan motor pushes
against the sail switch paddle, closing the sail switch
contacts, supplying power to the self-clean circuit. The
sail switch contacts must close for proper self-clean
operation.
Use the following procedure to check sail switch
contacts
for continuity.
1. Disconnect power from oven. Disconnect switch
wires.
2. Access sail switches by removing control panel
assembly.
3. Set ohmmeter in the low ohm range. Attach meter
leads to switch terminals on sail switch.
4. Meter should indicate no continuity or infinite ohms
when switch is in normal position.
5. Push switch paddle to close switch contacts. Meter
should indicate continuity or a low ohm reading.
6. Replace sail switch that failed the test.
NOTE: Both sail switches must be tested.
Vent Hi-Limit Control
OPEN CLOSED
145
°
F 185
°
F
1. Turn off power to
oven and disconnect gas
supply.
2. Remove oven from
wall cutout.
3. Remove screws securing outer cabinet top shield to
outer cabinet wrapper shield.
4. Disconnect wires from switch connections.
5. Attach ohmmeter leads to switch terminals. At
ambient room temperature 70
°
F, continuity
should be indicated.
Thermal Fan Switch
Thermal fan switches are mounted behind the control
panel. Fan switches monitor the temperature at the rear
of the oven cabinet and supply power to the fan motor
if the rear cabinet temperatures exceed 150
°
F.
Thermal fan switch contains three terminals. Terminal
1 is the common terminal connected to the power
source. Terminal 2 is the NO terminal connected to the
fan motors and terminal 3 is the NC terminal connected
to the oven elements.
During most cooking operations, the C-NC contacts
remain closed. When the oven rear cabinet
temperatures reach approximately 150
°
F, contacts C-
NC open and C-NO closes supplying power to the fan
motors. Use the following procedure to check contacts
C-NC for continuity.
1. Disconnect power to oven. Remove switch wiring.
2. Access thermal fan switches by removing the oven
from the cabinet and rear cabinet back panels
3. Set ohmmeter to low range.
4. Attach meter leads to switch terminal 1 or Com and
3 to NC.
5. Meter should indicate low ohms or continuity. It is
difficult to check fan switch contacts COM-NO
since they are closed when the rear cabinet
temperature reaches 150
°
F and above.
Terminals 1-2 (NO) closed @150
°
F open @ 120
°
F
Terminals 1-3 (NC) opened @150
°
F closed @ 120
°
F
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