Vc4Gd, Vc6Gd With Roast & Hold Option; Temperature Control) - Vulcan-Hart VC4G Service Manual

VC4G & VC6G SERIES FULL SIZE CONVECTION OVENS - ELECTRICAL OPERATION
a. Heat relay (R3) contacts (N.O.)
close and the heating circuit is
powered.
a)
b)
5. Oven reaches the fixed "Hold" temperature and
the hold thermostat opens.
A. Heat light goes out.
B. Power removed from heat relay (R3) and
the contacts open (N.O.).
1) Ignition control module de-energized.
a. Power removed from 2nd valve
(main) on the gas valve and gas
flow to the burner stops.
C. Power is also removed from motor speed
relay (R1).
1) Convection fan motor de-energized
and fan stops rotating.
F24682 Rev. D (1016)
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.
6. The oven will continue to cycle on the hold
thermostat until the "Cook & Hold timer is turned
to the OFF position, the function switch (S3) is
changed back to "Cook" (normal cooking) or the
power switch (S1) is turned to the OFF or COOL
DOWN position.
VC4GD, VC6GD With Roast & Hold Option (Solid
State Temperature Control)
Schematic diagram 5306 will be used to explain the
electrical sequence of operation for both the Normal
ROAST cycle (normal cooking) and the ROAST &
HOLD cycle.
Normal Roast Cycle
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" cycle.
G. Oven light switch (S2) ON/OFF (position
has no affect on the function of the "Cook"
cycle).
H. Temperature control dial set to lowest
temperature (fully counterclockwise).
I. High limit switch CLOSED.
J. Roast timer (normal cooking) in the OFF
position.
K. Roast and Hold timer in the OFF position.
L. Oven doors Closed.
1)
M. Oven cavity temperature below 140°F.
2. Set temperature control dial to desired ROAST
then HOLD temperature (Roast & Hold cooking).
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L1 (HOT) to power switch (S1).
L2 (NEUTRAL or SECOND LINE) to
one side of the following components:
power ON light, heat light, temperature
control board terminal 9 (120VAC) or
terminal 10 (208- 240VAC), oven
cavity lights, buzzer, "Cook" timer
motor (normal cooking), "Cook & Hold"
timer motor, heat relay coil (R3),
convection fan motor common (C),
transformer primary (T1), motor speed
(Hi/Low) relay coil (R1), hold relay coil
(R2) and the component cooling fan.
Door switch contacts CLOSED.