Vulcan-Hart SG4D service manual GAS Pressure Adjustment

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GAS PRESSURE ADJUSTMENT

Disconnect the electrical power to the machine and follow lockout / tagout procedures.

Accurate gas pressure adjustments can only be made with the gas on and the burner lit. If the incoming line pressure to the valve is less than the minimum stated, then the manifold pressure cannot be set correctly.

1.Turn gas supply off at manual shutoff valve.

2.Remove the right side panel as outlined under Covers and Panels in Removal and Replacement of Parts.

3.Remove the plug from the manifold pressure port.

4.Install hose barb adapter and attach manometer tube.

5.Remove adjustment screw cap from the gas valve and turn gas supply to the oven back on.

The following steps require power to be applied to the unit during test. Use extreme caution at all times.

6.Plug the unit in and turn the power switch ON.

7.Set the temperature controller to its highest setting and allow burner to ignite. The burner must be lit during test and adjustment.

8.Turn the set screw to obtain the proper gas pressure (clockwise = pressure increase; counterclockwise = pressure decrease).

		PRESSURE READINGS (IN W.C.)
GAS
GAS			LINE
TYPE			LINE
TYPE	MANIFOLD
	MANIFOLD		RECOMMENDED		MIN		MAX
			RECOMMENDED		MIN		MAX

Natural	3.5		7.0		5.0
							14
Propane	10		11.0		11.0		14
Propane	10		11.0		11.0

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Contents SG4 & SG6 Series Full Size GAS Convection Ovens VULCAN-HART Table of Contents Table of Contents General Component Location Removal and Replacement of PartsTop Front Cover Covers and PanelsBottom Front Cover Right Side PanelSG4D/SG6D SG4C/SG6C Control Panel ComponentsComponent Panel Components SG4C/SG6C Temperature Probe Shown Temperature ProbeGAS Burners GAS Solenoid Valve GAS OrificeSpark Igniter and Flame Sense Ignition Control ModuleBlower 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 Cooling FAN Fan Installation TipsSolid State Temperature Controller Test SG4D/SG6D Service Procedures and AdjustmentsTest Steps Calibration Steps Solid State Temperature Control Calibration SG4D/SG6DTemp F Ohms Temperature Probe Test SG4D/SG6DComputer Controller SG4C/SG6C Operation Setup ModeProbe Test Solid State Relay Test Computer Control Calibration SG4C/SG6CGAS Pressure Adjustment Verification of Spark AT Ignitor Door Switch AdjustmentFlame Current Measurement Blower AdjustmentDoor Strike Adjustment Independent Doors Door AdjustmentDoor Catch Roller Adjustment Component Description Electrical OperationPlug, Socket and Components SG4D/SG6D Front ViewFront View Control Panel Component PanelPlug, Socket and Components SG4C/SG6C Sequence of Operations SG4D/SG6D with Solid State Temperature ControllerCook Cycle Cool Down Cycle Solid State Temperature Controller Timer CycleNormal Cook Cycle SG4C/SG6C with Computer ControllerPage Roast and Hold Cycle Temperature and Time Cycle Normal CookingWiring Diagrams 426574 Rev. C Thermostat SchematicsGAS Convection Oven SG4 with Watlow 734 Control Symptoms Possible Causes TroubleshootingSymptoms Possible Causes Computer Control Models only Symptom Possible CausesError Codes Probable Cause Solution Problem