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

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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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Contents SG4 & SG6 Series Full Size GAS Convection Ovens VULCAN-HART Table of Contents Table of Contents General Removal and Replacement of Parts Component LocationBottom Front Cover Covers and PanelsTop Front Cover Right Side PanelControl Panel Components SG4D/SG6D SG4C/SG6CComponent Panel Components Temperature Probe SG4C/SG6C Temperature Probe ShownGAS Burners GAS Orifice GAS Solenoid ValveIgnition Control Module Spark Igniter and Flame SenseBlower and Motor Oven Doors and Bearings Door Catch Roller Assembly Independent Doors Roller Latch Assembly Independent DoorsDoor Window Door Switch High Limit Thermostat Lamp AssemblyInterior Lights Fan Installation Tips Cooling FANSolid State Temperature Controller Test SG4D/SG6D Service Procedures and AdjustmentsTest Steps Solid State Temperature Control Calibration SG4D/SG6D Calibration StepsTemperature Probe Test SG4D/SG6D Temp F OhmsComputer Controller SG4C/SG6C Operation Setup ModeProbe Test Computer Control Calibration SG4C/SG6C Solid State Relay TestGAS Pressure Adjustment Door Switch Adjustment Verification of Spark AT IgnitorBlower Adjustment Flame Current MeasurementDoor Adjustment Door Strike Adjustment Independent DoorsDoor Catch Roller Adjustment Electrical Operation Component DescriptionFront View Plug, Socket and Components SG4D/SG6DFront View Control Panel Component PanelPlug, Socket and Components SG4C/SG6C Sequence of Operations SG4D/SG6D with Solid State Temperature ControllerCook Cycle Timer Cycle Cool Down Cycle Solid State Temperature ControllerSG4C/SG6C with Computer Controller Normal Cook CyclePage Temperature and Time Cycle Normal Cooking Roast and Hold CycleWiring Diagrams 426574 Rev. C Schematics ThermostatGAS Convection Oven SG4 with Watlow 734 Control Troubleshooting Symptoms Possible CausesComputer Control Models only Symptom Possible Causes Symptoms Possible CausesError Codes Probable Cause Solution Problem
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