Vulcan-Hart VC4GC User manual

A product of VULCAN-HART LOUISVILLE, KY 40201-0696
F24682 (Rev. B, October 2007)
VC4GD WITH ROAST & HOLD SHOWN
SERVICE MANUAL
VC4G & VC6G SERIES
FULL SIZE
GAS CONVECTION OVENS
MODEL ML
VC4GS 126610
VC4GD 126611
VC4GC 136494
VC6GS 126612
VC6GD 126613
VC6GC 136495
- NOTICE -
This Manual is prepared for the use of trained Vulcan Service
Technicians and should not be used by those not properly qualified. If
you have attended a Vulcan Service School for this product, you may be
qualified to perform all the procedures described in this manual.
This manual is not intended to be all encompassing. If you have not
attended a Vulcan Service School for this product, you should read, in
its entirety, the repair procedure you wish to perform to determine if you
have the necessary tools, instruments and skills required to perform the
procedure. Procedures for which you do not have the necessary tools,
instruments and skills should be performed by a trained Vulcan Service
Technician.
Reproduction or other use of this Manual, without the express written
consent of Vulcan, is prohibited.
For additional information on Vulcan-Hart Company or to locate an authorized parts
and service provider in your area, visit our website at www.vulcanhart.com.

FULL SIZE GAS CONVECTION OVENS
F24682 (Rev. B, October 2007) Page 2 of 68
TABLE OF CONTENTS
GENERAL ................................................................................ 4
Introduction ............................................................................ 4
Installation ............................................................................ 4
Operation ............................................................................. 4
Cleaning .............................................................................. 4
Lubrication ............................................................................ 4
Specifications .......................................................................... 4
Tools................................................................................. 4
REMOVALANDREPLACEMENTOFPARTS .................................................... 5
Covers and Panels ...................................................................... 5
Control Panel Components ............................................................... 6
Component Panel Components ............................................................ 7
Temperature Probe (VC4GD/6GD) ......................................................... 8
GasBurner ............................................................................ 8
GasOrifice ............................................................................ 9
Gas Solenoid Valve ..................................................................... 9
Ignition Control Module .................................................................. 10
Spark Igniter and Flame Sense ........................................................... 10
Blower and Motor ...................................................................... 11
Oven Doors and Bearings (Independent Doors) .............................................. 12
Oven Doors (Simultaneous Doors) ......................................................... 13
RollerLatchAssembly .................................................................. 14
Door Catch Ball Assembly (Independent Doors) .............................................. 15
Door Window ......................................................................... 15
DoorSwitch .......................................................................... 16
Mechanical KX Thermostat (VC4GS/6GS) ................................................... 16
HighLimitThermostat .................................................................. 16
InteriorLights ......................................................................... 17
CoolingFan .......................................................................... 18
Service Procedures and Adjustments .......................................................... 19
SolidStateTemperatureControlCalibration(VC4GD/6GD) ..................................... 19
Mechanical Thermostat Calibration (VC4GS/6GS) ............................................ 20
SolidStateTemperatureControlTest(VC4GD/6GD) .......................................... 20
Temperature Probe Test (VC4GD/6GD) .................................................... 21
GasPressureAdjustment................................................................ 22
VerificationofSparkatIgnitor ............................................................ 23
DoorSwitchAdjustment ................................................................. 23
BlowerAdjustment ..................................................................... 24
DoorAdjustment....................................................................... 25
Door Strike Adjustment (Independent Doors) ................................................. 25
Door Catch Ball Adjustment (Independent Doors) ............................................. 26
Door Chain Adjustment (Simultaneous Doors) ................................................ 27

FULL SIZE GAS CONVECTION OVENS
F24682 (Rev. B, October 2007)Page 3 of 68
ComputerControl(VC4GC/VC6GC) ....................................................... 28
ComputerControlCalibration(VC4GC/VC6GC) .............................................. 29
ELECTRICALOPERATION .................................................................. 30
Component Function ................................................................... 30
Component Location ................................................................... 32
Sequence of Operation .................................................................. 37
VC4GS, VC6GS With Roast & Hold Option (Mechanical KX Thermostat) ....................... 37
VC4GD,VC6GDWithRoast&HoldOption(SolidStateTemperatureControl) .................. 41
CoolDownCycle(SolidStateTemperatureControl) ....................................... 46
VC4GC, VC6GC (Roast & Hold Standard on Computer Model) .............................. 46
Cool Down Cycle (Computer Control Model) ............................................. 49
Schematics ........................................................................... 50
VC4GS, VC6GS Mechanical (KX) Controls .............................................. 50
VC4GS, VC6GS Mechanical (KX) Controls, Roast & Hold Option ............................. 51
VC4GD,VC6GDSolidStateTemperatureControl ........................................ 52
VC4GD,VC6GDSolidStateTemperatureControl,Roast&HoldOption ....................... 53
VC4GC, VC6GC Computer Control (Roast & Hold Standard) ................................ 54
WiringDiagrams ....................................................................... 56
VC4GS, VC6GS Mechanical (KX) Controls .............................................. 56
VC4GS, VC6GS Mechanical (KX) Controls, Roast & Hold Option ............................. 58
VC4GD,VC6GDSolidStateTemperatureControl ........................................ 60
VC4GD,VC6GDSolidStateTemperatureControl,Roast&HoldOption ....................... 62
VC4GC, VC6GC Computer Control (Roast & Hold Standard) ................................ 64
TROUBLESHOOTING ...................................................................... 66
All Models ............................................................................ 66
Computer Control Models Only ........................................................... 67
© Vulcan 2007

FULL SIZE GAS CONVECTION OVEN - GENERAL
F24682 (Rev. B, October 2007) Page 4 of 68
GENERAL
INTRODUCTION
Procedures in this manual will apply to all models unless specified. Pictures and illustrations can be of any model
unless the picture or illustration needs to be model specific.
Models
MODEL
FEATURES OPTIONS
CAVITY
DEPTH
TEMPERATURE
CONTROL
DOORS
(50/50)
NORMAL
(ROAST)
TIMER
NORMAL
TIMER OR
HOLD
TIMER
ROAST
&
HOLD
BLOWER
208/240/60/1
VC4GS 26.5" Mechanical (KX) Independent 1, 2 1-Hour Dial 5-Hour Dial Optional Optional
VC6GS 30.5" Mechanical (KX) Independent 1, 2 1-Hour Dial 5-Hour Dial Optional Optional
VC4GD 26.5" Solid State Independent 1, 3 1-Hour Dial 5-Hour Dial Optional Optional
VC6GD 30.5" Solid State Independent 1, 3 1-Hour Dial 5-Hour Dial Optional Optional
VC4GC 26.5" Computer Independent 1, 3 24-Hour Digital Built in Built in Optional
VC6GC 30.5" Computer Independent 1, 3 24-Hour Digital Built in Built in Optional
1. Simultaneous doors are optional (with or w/o window).
2. Stainless steel doors w/o window (standard).
3. Stainless steel doors with window (standard).
INSTALLATION
Refer to the Installation and Operation Manual for
detailed installation instructions on single or stacked
ovens.
OPERATION
Refer to the Installation and Operation Manual for
specific operating instructions.
CLEANING
Refer to the Installation and Operation Manual for
specific cleaning instructions.
LUBRICATION
!Cavity blower motor has sealed bearings and
requires no additional lubrication.
!Huskey’s TF1000 grease or equivalent high
temperature Teflon grease.
SPECIFICATIONS
Electrical
Voltage - 120/60/1
Amps - 9.0 Amps
Input BTU Rating
Natural Gas - 44,000 BTU input at 3.5 in. W.C.
Propane Gas - 44,000 BTU input at 10.0 in. W.C.
Gas Line Pressures
Natural - Recommend (in. W.C.) 7.0, Min 5.0
Propane - Recommend (in. W.C.) 11.0, Min 11.0
Maximum 14.0 in. W.C. (Nat. or Prop.)
TOOLS
Standard
!Standard set of hand tools.
!VOM with A.C. current tester (Any quality VOM
with a sensitivity of at least 20,000 ohms per
volt can be used).
!Gear Puller to remove blower
Special
!Temperature tester (thermocouple type).
!Manometer

FULL SIZE GAS CONVECTION OVENS - REMOVAL AND REPLACEMENT OF PARTS
F24682 (Rev. B, October 2007)Page 5 of 68
REMOVAL AND REPLACEMENT OF PARTS
COVERS AND PANELS
Top Front Cover
1. The top front cover is secured with four (4)
screws, two on each side of cover. Remove
these screws then remove the cover from the
oven.
2. Reverse the procedure to install.
Bottom Front Cover
1. The bottom front cover is secured with four (4)
screws, two on each side of cover. Remove
these screws then remove the cover from the
oven.
2. Reverse the procedure to install.
Control Panel
1. Remove three (3) screws on the right side
which secure the control panel then pull the
panel away from the oven.
NOTE: If the oven has a mechanical (KX type)
thermostat, it must be removed from the control
panel first, before removing the control panel.
2. Disconnect the temperature probe leads from
the solid state temperature control.
3. Unplug the wire harness connector to the
control panel components.
4. Reverse the procedure to install.
Right Side Panel
1. Remove the screws which secure the right side
of the top front cover, bottom front cover and
control panel.
2. Remove the remaining six screws securing the
right side panel.
3. Pull the right side panel out at the bottom then
down to remove.
4. Reverse the procedure to install.

FULL SIZE GAS CONVECTION OVENS - REMOVAL AND REPLACEMENT OF PARTS
F24682 (Rev. B, October 2007) Page 6 of 68
CONTROL PANEL
COMPONENTS
Removable Components Procedure
1. Remove the control panel as outlined under
COVERS AND PANELS.
2. Remove the component being replaced.
3. Reverse the procedure to install the
replacement component, then check oven for
proper operation.

FULL SIZE GAS CONVECTION OVENS - REMOVAL AND REPLACEMENT OF PARTS
F24682 (Rev. B, October 2007)Page 7 of 68
COMPONENT PANEL
COMPONENTS
Removable Components Procedure
1. Remove the right side panel as outlined under
COVERS AND PANELS.
NOTE: If right side panel is not accessible, this
component can be serviced by removing the control
panel as outlined under COVERS AND PANELS.
2. Disconnect the wire leads to the component
being replaced.
3. Remove the component.
4. Reverse the procedure to install the
replacement component and check oven for
proper operation.

FULL SIZE GAS CONVECTION OVENS - REMOVAL AND REPLACEMENT OF PARTS
F24682 (Rev. B, October 2007) Page 8 of 68
TEMPERATURE PROBE
(VC4GD/6GD)
1. Remove the right side panel as outlined under
COVERS AND PANELS.
NOTE: If right side panel is not accessible, this
component can be serviced by removing the control
panel as outlined under COVERS AND PANELS.
2. Disconnect the probe leads from the
temperature control.
3. Remove the racks and right rack support.
4. Remove probe clips from probe.
5. Push the probe through the opening in cavity
side wall and into the control panel area.
NOTE: The hole in the oven cavity wall does not line
up straight with the oven cavity outer shell, therefore
the probe must be removed at an angle.
6. Reverse the procedure to install the
replacement probe.
7. Adjust the temperature control as outlined under
SOLID STATE TEMPERATURE CONTROL
CALIBRATION (VC4GD/6GD) in SERVICE
PROCEDURES AND ADJUSTMENTS.
GAS BURNER
Shut off the gas before servicing
the unit.
1. Remove the lower front cover as outlined under
COVERS AND PANELS.
2. Disconnect the ignition cable and the flame
sense lead wire.
3. Remove the bolts securing the gas manifold
and place manifold aside.
4. Remove the screws securing the burner cover
then lift out.
5. Grasp the burner and lift out.

FULL SIZE GAS CONVECTION OVENS - REMOVAL AND REPLACEMENT OF PARTS
F24682 (Rev. B, October 2007)Page 9 of 68
6. Reverse procedure to install the replacement
burner.
NOTE: Ensure that burner positioning bracket (U
shaped end) is inserted into slot at the rear of the
burner chamber.
7. Check for proper operation.
GAS ORIFICE
Shut off the gas before servicing
the unit.
1. Remove the bottom front cover as outlined
under COVERS AND PANELS.
2. Remove the bolts securing the gas manifold to
the oven and place the manifold to the side.
3. Remove the gas orifice from the spud on the
manifold and replace with the correct orifice for
the given altitude.
4. Reverse procedure to install and check for
proper operation.
GAS SOLENOID VALVE
Shut off the gas before servicing
the unit.
All gas joints disturbed during
servicing must be checked for leaks. Check with
a soap and water solution (bubbles). Do not use
an open flame.
1. Remove the control panel and the right side
panel as outlined under COVERS AND
PANELS.
NOTE: If right side panel is not accessible, this
component can be serviced by removing the control
panel as outlined under COVERS AND PANELS.
2. Disconnect the lead wires.
3. Disconnect the compression fittings to the
valve.

FULL SIZE GAS CONVECTION OVENS - REMOVAL AND REPLACEMENT OF PARTS
F24682 (Rev. B, October 2007) Page 10 of 68
4. Loosen the bolts securing the valve and bracket
assembly then remove the screws securing the
valve to the bracket.
5. Reverse the procedure to install the
replacement gas valve.
NOTE: Clean the pipe threads and apply pipe joint
compound to threads. Any pipe joint compound
used, must be resistant to the action of propane
gases.
6. Verify gas pressure as outlined under GAS
PRESSURE ADJUSTMENT in SERVICE
PROCEDURES AND ADJUSTMENTS and
check for proper operation.
IGNITION CONTROL MODULE
Shut off the gas before servicing
the unit.
1. Remove the right side panel as outlined under
COVERS AND PANELS.
NOTE: If right side panel is not accessible, this
component can be serviced by removing the control
panel as outlined under COVERS AND PANELS.
2. Loosen the screws securing the mounting
bracket to the component panel and remove the
bracket.
3. Disconnect the lead wires and igniter cable from
the ignition module board.
4. Remove the ignition module board from the
mounting bracket.
5. Reverse the procedure to install the
replacement ignition module board.
SPARK IGNITER AND
FLAME SENSE
Shut off the gas before servicing
the unit.
1. Remove the gas burner as outlined under GAS
BURNER.
2. Remove the screws securing the ignitor and
flame sense to burner then remove the
assembly.