Wolf WKGD 126621 Convection Oven User Manual


 
FULL SIZE GAS CONVECTION OVENS - ELECTRICAL OPERATION
F32700 (February 2006)Page 29 of 64
Blower Motor ................. Operates the oven cavity blower (convection fan). Also, an internal
centrifugal switch on the motor is utilized to allow the connection of power
to the heat relay (R3) when the motor is at operating speed.
Motor Speed Relay (R1)......... Supplies power to the blower motor through (R1) relay contacts. Available
on models with Roast & Hold option only.
Hold Relay (R2)................ Hold relay (R2) supplies power to the Hold thermostat for maintaining the
fixed hold temperature in the oven cavity, after the ROAST & HOLD time
expires.
Transformer (T1)............... Provides 24VAC power to the ignition control module and heating circuit.
Solid State Temperature Control
(WKGD/WKGDX)............... Monitors temperature sensor and regulates the oven cavity temperature by
controlling the heat relay (R3) through the blower motor centrifugal switch
contacts.
High Limit Thermostat .......... Protects the oven from temperatures above 550°F by removing power from
the 1
st
valve (safety) on the dual solenoid gas valve which stops the flow of
gas to the burner. Auto resets at 500°F.
Computer Control
(WKGC/WKGCX)............... Monitors temperature sensor and regulates the oven cavity temperature by
controlling the heat relay (R1) through the blower motor centrifugal switch
contacts. Also, counts the ROAST time (normal cooking) of the product and
signals the electronic alarm at the end of the cycle. If ROAST & HOLD
mode is selected, when the ROAST (then hold) time expires, the oven
heating stops and the oven enters HOLD mode. Once the oven cavity
temperature drops to 150°F, the heat comes back on and the oven cycles
at this temperature to hold the cooked product. Roast & Hold is standard on
computer models.
SSR1 & SSR2 (WKGC/WKGCX) . . When SSR1 is energized by computer control, connects power to blower
motor for Hi fan speed operation in normal ROAST mode. In ROAST &
HOLD Mode only, SSR1 is de-energized and SSR2 is energized by
computer control and connects power to blower motor for Low fan speed
operation.
Ignition Control Module ......... Controls the gas ignition cycle - Energizes the 2
nd
valve (main) on the dual
solenoid gas valve, generates spark for burner ignition, monitors the
presence of a flame and controls the No Ignition light. The ignition times
are: 4 second self diagnostic test (initial power ON); 7 second ignition trial;
3 ignition trials with a 15 second purge between each trial.
Igniter/Flame Sense ............ Ignites the gas and senses the presence of a flame. The flame presence
generates a micro-amp FLAME SENSE current that is monitored by the
ignition control module. A flame sense current of 0.7 micro amp (minimum)
is required to maintain burner ignition.
Power On Light................ Lit whenever the power switch (S1) is turned to ON or Oven Cool mode.
Heat Light .................... Lit whenever temperature control is calling for heat.
No Ignition Light............... Lit when power is turned ON, during ignition trial & gas purge time and
when no flame is detected by flame sensor. If the oven fails to ignite after 3
attempts, it will remain lit until power is reset.