Vulcan-Hart VC4G Service Manual page 45

VC4G & VC6G SERIES FULL SIZE CONVECTION OVENS - ELECTRICAL OPERATION
a)
b. When the convection fan motor
reaches operating speed, the
centrifugal switch on the motor
closes. The heat relay (R3) is then
energized, R3 relay contacts
normally open (N.O.) close and
the heating circuit is powered.
a)
b)
4. Oven reaches set temperature and thermostat
opens.
A. Heat light goes out.
B. Power removed from heat relay (R3).
1) R3 normally open (N.O.) contacts
open.
a. Power removed from 2nd valve
(main) on the gas valve and gas
flow to the burner stops.
Power is connected through
the function switch (S3)
contacts and the convection
fan motor is energized (fan
speed Hi).
Ignition control module is
energized.
No ignition light (red) comes
ON, module performs a self
diagnostic test for 4 seconds,
2nd valve (main) on the gas
valve is energized. Gas
starts to flow to the burner,
sparking begins, the "no
ignition" light goes out and
burner lights. Sparking
continues for up to 7 seconds
or until a flame is
established. If a flame is
"sensed", the "no ignition"
light stays out and burner
remains lit.
If a flame is not "sensed"
after 7 seconds of sparking,
the "no ignition" light comes
back on, 2nd valve (main) on
the gas valve is de-energize
and gas flow to the burner
stops. Ignition trial cycle
repeats after a 15 second
purge between cycles for two
additional tries before
locking out. To reset after a
lockout, turn power switch
(S1) OFF then ON.
5. The oven will continue to cycle on the thermostat
until the doors are opened or the power switch
(S1) is turned to the OFF or COOL DOWN
position.
Timer Cycle (Normal Roast Cooking)
NOTE: The ROAST timer (normal cooking) operates
independently of the heating cycle. Additional time
can be set or the timer can be turned OFF throughout
the cooking cycle.
1. With the power switch turned ON, power is
supplied to timer.
2. Set ROAST timer to desired time (normal
cooking).
A. Contacts 1 & 3 close, timer motor is
energized and timing "down" begins.
3. Time expires on ROAST timer (normal cooking).
A. Contacts 1 & 3 open, timer motor is de-
energize and timing stops.
B. Contacts 1 & 4 close.
1)
NOTE: The buzzer continues to sound until the timer
dial is set to the OFF position or additional time is set.
Roast and Hold Cycle
NOTE: Refer to the Installation and Operation Manual
for a detailed explanation of ROAST & HOLD cooking.
1. Conditions.
A. Oven connected to correct voltage.
1)
2)
B. Oven properly grounded.
C. Gas supply valve ON.
D. Gas combination control valve ON.
E. Power switch (S1) OFF.
F. Function switch (S3) set to "Cook & Hold"
cycle.
G. Oven light switch (S2) ON/OFF (position
has no affect on the function of the Cook &
Hold cycle).
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Buzzer energized and sounds.
L1 (HOT) to power switch (S1).
L2 (NEUTRAL or SECOND LINE) to
one side of the following components:
power ON light, heat light, oven cavity
lights, buzzer, "Cook" timer motor
(normal cooking), "Cook & Hold" timer
motor, heat relay coil (R3), convection
fan motor (C), transformer primary
(T1), relay coil (R4), motor speed relay
coil (R1), hold relay coil (R2) and the
component cooling fan.
F24682 Rev. D (1016)