Vulcan-Hart SG4D service manual Timer Cycle, Cool Down Cycle Solid State Temperature Controller

4.Heating circuit is powered.

A.No ignition light (red) comes ON.

B.Module performs a self diagnostic test for 4 seconds.

C.Second valve (main) on the gas valve is energized. Gas starts to flow to burners.

D.Sparking begins, the no ignition light goes out and burners light.

NOTE: Sparking continues for up to 7 seconds or until a flame is established on both burners. If a flame is sensed on both burners, the no ignition light stays out and burner remains lit. If a flame is not sensed on both burners after 7 seconds of sparking, the no ignition light comes back on, second valve (main) on the gas valve is de-energized 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.Oven reaches set temperature.

A.Temperature controller de-energizes internal relay and the normally open (N.O.) contacts open.

1)Heat light goes out.

B.Power removed from heat relay.

C.Heat relay normally open (N.O.) contacts OPEN.

D.Power removed from heating circuit.

1)Second gas valve de-energized.

6.The oven will continue to cycle on the temperature controller until the doors are opened or master switch (S1) is turned to the OFF or OVEN COOL position.

Timer Cycle

The timer 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 master switch turned ON, power is supplied to timer.

A.Set the timer to desired time.

B.Contacts 1 & 3 close, timer motor is energized and timing down begins.

2.Time expires on timer.

A.Contacts 1 & 3 open, timer motor is de-energized and timing stops.

B.Contacts 1 & 4 close.

1)Buzzer energized and sounds. The buzzer continues to sound until the timer dial is set to the OFF position or additional time is set.

Cool Down Cycle (Solid State Temperature Controller)

1.Conditions.

A.Oven is ON.

B.Oven cavity temperature needs to be lowered.

C.Doors are open.

1)Convection fan de-energized.

2)Thermostat de-energized.

a.Heat light out.

b.Power removed from heat relay.

3)24 V transformer de-energized.

4)Cooling fan de-energized.

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