FULL SIZE GAS CONVECTION OVENS - ELECTRICAL OPERATION
1)R3 normally open (N.O.) contacts open.
a.Ignition control module de- energized.
a)Power removed from 2nd valve (main) on the gas valve and gas flow to the burner stops.
NOTE: This is considered first stage cooking in the ROAST AND HOLD cycle.
5.The oven will continue to cycle on the controlling thermostat until one of the following occurs: ROAST & HOLD time (R & H cooking) expires which allows the oven to go into Hold mode; Power switch (S1) is turned to the OFF or OVEN COOL position or the doors are opened.
Timer Cycle (Roast & Hold Cooking)
NOTE: The ROAST & HOLD timer operates independently of the heating cycle until time expires. Regulation of the oven temperature is then transferred to the Hold thermostat until one of the following occurs: ROAST & HOLD timer is turned OFF and the function switch (S3) is turned back to Normal ROAST (normal cooking) or power switch (S1) is turned to the OFF or OVEN COOL position.
1.With the power switch turned ON, power is supplied to timer.
2.Set ROAST & HOLD timer to desired time (Roast & Hold cooking).
NOTE: To Roast then Hold the cooked product at a fixed temperature, the Roast & Hold timer must be used and the function switch (S3) must also be set to Roast & Hold as indicated under step1 conditions for the Roast & Hold cycle.
A.Contacts 1 & 3 close, timer motor is energized and timing DOWN begins.
3.Time expires on Roast & Hold timer.
A.Contacts 1 & 3 open, timer motor is de- energized and timing stops.
B.Contacts 1 & 4 close.
1)If the oven was heating, then the gas burner and heat light go out; If the oven was not heating, then the gas burner and heat light remain out.
2)Hold relay (R2) is energized, R2 contacts change state and the normally open (N.O.) contacts close.
a.Power to one side of hold thermostat.
NOTE: When temperature is above 160°F (±12) the hold thermostat contacts are open.
3)Relay R4 is energized, R4 contacts change state and both sets of normally closed (N.C.) contacts transfer to the normally open (N.O.) position. Power is not transferred until the hold thermostat contacts close.
NOTE: This is considered second stage cooking in the ROAST AND HOLD cycle where the stored heat in the oven continues to cook the product.
4.Oven temperature falls below 160°F (±12) and hold thermostat contacts close.
A.Heat light comes ON.
B.Motor speed relay (R1) is energized through one set of R4 (N.C.) contacts.
1)Convection fan motor energized (fan speed low).
C.Power is applied to one side of the centrifugal switch on the convection fan motor through the other set of R4 (N.C.) contacts.
D.When the convection fan motor reaches operating speed, the centrifugal switch on the motor closes.
1)Heat relay (R3) is energized.
a.Heat relay (R3) contacts (N.O.) close and the heating circuit is powered.
a)Ignition control module is energized.
b)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
F32700 (February 2006) |
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