Gas Model - Vulcan-Hart VGCTS16 Service Manual

ROUND TILTING BRAISING PANS - ELECTRICAL OPERATION

Gas Model

1. Conditions.
A. Unit connected to correct voltage, polarity
is correct and is properly grounded.
B. Power switch OFF.
C. Gas supply valve is ON.
D. Limit switch closed (pan down).
E. Thermostat (potentiometer) dial OFF ( 0
ohms between wiper arm terminal (red
lead) & one side of the coil (white lead)
CW rotation).
F. Temperature controller internal relay
contacts (N.O.) are open.
G. Temperature light off.
H. Ignition light off.
I. High limit thermostat contacts (N.C.)
closed.
2. Power switch ON.
A. Temperature controller receives power
from L1 (120VAC) and NEUTRAL and is
energized through L1 & L2 terminals on
controller.
B. L1 (120VAC) to the common side of
internal relay contacts.
C. NEUTRAL to one side of the temperature
light and step down transformer (120VAC
to 24VAC).
3. Turn thermostat (potentiometer) dial until a call
for heat is made.
A. Internal relay on temperature controller is
energized and the (N.O.) contacts close.
B. Power from L1 (120VAC) is then supplied
to the other side of the temperature light
and the step down transformer (120VAC to
24VAC).
1) Temperature light comes on and the
step down transformer is energized.
4. Ignition module is energized (24VAC) through
the high limit (N.C.) contacts and ground.
A. Ignition trial cycle begins.
1) Module delays energizing HSI for a 5
second purge time to allow any
residual gas to dissipate. After purge
time elapses, HSI begins a 3 second
heat up time.
2) After HSI heat up time elapses, the
gas solenoid valve opens to supply
gas to the hot ignitor and the ignition
light comes on.
3)
4)
5. Temperature controller reaches set point
temperature.
A. Internal relay on temperature controller is
de-energized and the contacts open.
B. Temperature light goes out.
C. Power is removed from the ignition control
module.
1)
2)
3)
6. Temperature controller drops below set point.
A. Cooking surface temperature is
maintained by the gas burner cycling with
the temperature controller until the
potentiometer dial is turned to the OFF
position or the power switch is turned OFF.
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When burner lights, flame sense
probe detects flame, HSI de-
energizes after an 8.5 second ignition
trial time, gas solenoid valve stays
open and heating begins.
If burner flame is not detected after
ignition trial time elapses, then the
ignition control module locks out
power to the gas solenoid valve. The
module remains locked out until the
thermostat (potentiometer) dial is
turned to OFF then back to a set
point temperature or the power switch
is turned OFF then back ON again.
Gas solenoid valve closes.
Burner shuts off.
Ignition light goes out.