Vulcan VC66EC, VC44ED, VC6ED, VC4ED, VC44EC Service Manual

SERVICE MANUAL

VC4E & VC6E Series Full Size
Electric Convection Ovens

VC4ES ML-126743
VC4ED ML-126744
VC4EC ML-126745
VC6ES ML-126746
VC6ED ML-126747
VC6EC ML-126748

- NOTICE -

This Manual is prepared for the use of trained Vulcan Service
Technicians and should not be used by those not properly
qualified.

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.

The reproduction, transfer, sale or other use of this Manual,
without the express written consent of Vulcan, is prohibited.

This manual has been provided to you by ITW Food Equipment
Group LLC ("ITW FEG") without charge and remains the property
of ITW FEG, and by accepting this manual you agree that you will
return it to ITW FEG promptly upon its request for such return at
any time in the future.

A product of Vulcan-Hart 3600 North Point Blvd Baltimore, MD 21222

F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens

TABLE OF CONTENTS

SERVICE UPDATES ....................................................................................... 4

SERVICE UPDATES - VC4E / VC6E .................................................................... 4

TIS DOCUMENT LIST - VC4E AND VC6E .............................................................. 4

GENERAL .................................................................................................. 6

INTRODUCTION ....................................................................................... 6

INSTALLATION ........................................................................................ 6

OPERATION ........................................................................................... 6

CLEANING ............................................................................................. 6

LUBRICATION ......................................................................................... 6

TOOLS ................................................................................................. 7

SPECIFICATIONS ...................................................................................... 7

REMOVAL AND REPLACEMENT OF PARTS ............................................................... 8

COVERS AND PANELS ................................................................................ 8

CONTROL PANEL COMPONENTS ..................................................................... 9

COMPONENT PANEL COMPONENTS ................................................................ 10

TEMPERATURE PROBE (SOLID STATE CONTROL) .................................................. 11

HEATING ELEMENTS ENDING AT SERIAL NUMBER 481916863 ..................................... 12

HEATING ELEMENTS STARTING AT SERIAL NUMBER 481916864 ................................... 13

BLOWER AND MOTOR ENDING AT SERIAL NUMBER 481916863 .................................... 15

BLOWER AND MOTOR STARTING AT SERIAL NUMBER 481916864 ................................. 16

DOOR SWITCH ....................................................................................... 17

DOOR WINDOW ...................................................................................... 18

OVEN DOORS AND BEARINGS (INDEPENDENT DOORS) ENDING AT SERIAL

NUMBER 481916782 .............................................................................. 18

OVEN DOORS (INDEPENDENT DOORS) STARTING AT SERIAL NUMBER 481916783 ............... 19

OVEN DOORS (SIMULTANEOUS DOORS) ENDING AT SERIAL NUMBER 481916783 ................ 20

OVEN DOORS (SIMULTANEOUS DOORS) STARTING AT SERIAL NUMBER 481916783 .............. 21

ROLLER LATCH ASSEMBLY (INDEPENDENT DOORS) ............................................... 22

DOOR CATCH ROLLER ASSEMBLY (INDEPENDENT DOORS) ....................................... 22

MECHANICAL (KX) THERMOSTAT ................................................................... 22

HIGH LIMIT THERMOSTAT ........................................................................... 23

INTERIOR LIGHTS (REAR MOUNTED, ROUND) ...................................................... 23

INTERIOR LIGHTS (SIDE MOUNTED, SQUARE) ...................................................... 24

COOLING FAN ........................................................................................ 26

SERVICE PROCEDURES AND ADJUSTMENTS ........................................................... 27

SOLID STATE TEMPERATURE CONTROL CALIBRATION ............................................ 27

MECHANICAL (KX) THERMOSTAT CALIBRATION .................................................... 29

SOLID STATE TEMPERATURE CONTROL TEST ..................................................... 30

TEMPERATURE PROBE TEST (SOLID STATE CONTROL) ........................................... 31

HEATING ELEMENT TEST ............................................................................ 32

BLOWER ADJUSTMENT .............................................................................. 33

DOOR ADJUSTMENT ................................................................................. 33

DOOR STRIKE ADJUSTMENT (INDEPENDENT DOORS) ............................................. 34

DOOR CATCH ROLLER ADJUSTMENT (INDEPENDENT DOORS) .................................... 35

DOOR SWITCH ADJUSTMENT ....................................................................... 36

DOOR CHAIN ADJUSTMENT (SIMULATANEOUS DOORS) ........................................... 37

COMPUTER CONTROL ............................................................................... 37

COMPUTER CONTROL TEMPERATURE CALIBRATION .............................................. 39

COMPUTER CONTROL OPERATIONAL TEST ........................................................ 40

ELECTRICAL OPERATION ................................................................................ 42

COMPONENT FUNCTION ............................................................................ 42

COMPONENT LOCATION ............................................................................. 43

SEQUENCE OF OPERATION - VC4ES, VC6ES WITH MECHANICAL KX THERMOSTAT .............. 48

F25105 Rev. C (1118) Page 2 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens

SEQUENCE OF OPERATION - VC4ED, VC6ED WITH SOLID STATE TEMPERATURE CONTROL ..... 48

SEQUENCE OF OPERATION - VC4EC, VC6EC (COMPUTER CONTROL) ............................. 49

SCHEMATICS AND WIRING DIAGRAMS .............................................................. 51

TROUBLESHOOTING ..................................................................................... 72

ALL MODELS ......................................................................................... 72

COMPUTER CONTROL MODELS ONLY .............................................................. 73

© VULCAN 2018

Page 3 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE UPDATES

SERVICE UPDATES

SERVICE UPDATES - VC4E / VC6E

October 2018

• HEATING ELEMENTS Starting at Serial Number
481916864

• BLOWER AND MOTOR Starting at Serial
Number 481916864

• INTERIOR LIGHTS (Rear Mounted, Round)

• INTERIOR LIGHTS (Side Mounted, Square)

• DOOR ADJUSTMENT

• OVEN DOORS (INDEPENDENT DOORS)
Starting at Serial Number 481916783

• OVEN DOORS (SIMULTANEOUS DOORS)
Starting at Serial Number 481916783

• COMPONENT LOCATION

• SCHEMATICS AND WIRING DIAGRAMS

TIS DOCUMENT LIST - VC4E AND VC6E

SERVICE TAB

Document Title Document Type

VC4E and VC6E Service Manual Service Manual

NCC Temp Control with Harness Service Kit Instructions (SKI)

SERVICE TAB (Multimedia)

Document Title Document Type

Repair Flood-Damaged Equipment Service Bulletin

VC3, VC4ED, and VC6ED & VC6EC Series Electric Convection Ovens I&O
Manual

VC3, VC4, and VC6 Series Electric Convection Oven Operator Operator

Fundamentals of Gas Service Instructions

TSB 1037A Hobart to Vulcan "Common" Model Cross Reference List Technical Service Bulletin (TSB)

Convection Oven Computer Control Guide Operator

Rating Plate Locationson Current Vulcan-Hart/Wolf Range Equipment Technical Service Bulletin (TSB)

Convection Ovens Gas and Electric Service Instructions

SB770R Door Latch Change on Full Size Convection Ovens (VC4, VC6,
SG, WKG, & WKE)

SB880 Independent Door Handle Assembly for Convection Ovens Technical Service Bulletin (TSB)

SB930 Convection Oven Door Switch Replacement for Wolf Challenger XL
and the Vulcan Endurance Gas Ranges

TSB 0368 Fast Thermostatic Controlled Convection Ovens Technical Service Bulletin (TSB)

TSB 0652C Digital Countdown Timer Change - Convection Ovens Technical Service Bulletin (TSB)

TSB 0872 Full Size Convection Oven-Door chain Adjustment Not Holding Technical Service Bulletin (TSB)

TSB 0874 Full Size Convection Ovens - Lighting & Cooling Fan Technical Service Bulletin (TSB)

TSB 0934 Gas Convection Ovens, Blower Motor & Wheel Change Technical Service Bulletin (TSB)

TSB 0934 Programmable Controls - 355452-2 (Rev. 4.0) Technical Service Bulletin (TSB)

Operator

Technical Service Bulletin (TSB)

Technical Service Bulletin (TSB)

F25105 Rev. C (1118) Page 4 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE UPDATES

SERVICE TAB (Multimedia)

All Half Size & Full Size Unites w/Independent Opening Doors -Enhanced
Door Catch Info.

Watlow 734C Computer Control Technical Service Instructions (TSI)

Vulcan & Wolf Gas Convection Ovens with White Rodgers Gas Valve Technical Service Instructions (TSI)

PARTS TAB

Document Title Document Type

Part Catalog for VC4E and VC6E Parts Catalog

DIAGRAMS TAB

Document Title Document Type

HGC5, DGC5, VC4G, WKGD Series Wiring Diagram

Technical Service Bulletin (TSB)

Page 5 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - GENERAL

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.

FEATURES

MODEL CAVITY DEPTH

VC4ES

VC4ED 26.5" Solid State Independent (see note 1,3) 1-Hour Dial

VC4EC 26.5" Computer Independent (see note 1,3) 24-Hour Digital

VC6ES

VC6ED 30.5" Solid State Independent (see note 1,3) 1-Hour Dial

VC6EC 30.5" Computer Independent (see note 1,3) 24-Hour Digital

NOTES:

4

4

26.5" Mechanical (KX) Independent (see note 1,2) 1-Hour Dial

30.5" Mechanical (KX) Independent (see note 1,2) 1-Hour Dial

1

Simultaneous doors are optional (with or w/o window).

TEMPERATURE

CONTROL

2

Stainless steel doors w/o window (standard).

3

Stainless steel doors with window (standard)

4

In February 2001, this model was discontinued.

DOORS (50/50) COOK TIMER

OPTIONS

MODEL COOK TIMER ROAST & HOLD

VC4ES

VC4ED 5-Hour Dial N/A

VC4EC Built in Built in

VC6ES

VC6ED 5-Hour Dial N/A

VC6EC Built in Built in

4

4

INSTALLATION

Refer to the Instructions Manual F31159 for detailed
installation instructions on single or stacked ovens.

OPERATION

Refer to the Instructions Manual F31159 for specific
operating instructions.

5-Hour Dial N/A

5-Hour Dial N/A

CLEANING

Refer to the Instructions Manual F31159 for specific
cleaning instructions.

LUBRICATION

• Cavity blower motor has sealed bearings and
requires no additional lubrication.

• Huskey’s TF1000 grease or equivalent high
temperature non-stick grease.

F25105 Rev. C (1118) Page 6 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - GENERAL

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

• Temperature tester (thermocouple type)

SPECIFICATIONS

AMPERAGE - 3 PHASE/ 60HZ

MODEL

VC4ES

VC4ED

VC4EC

VC6ES

TOTAL

POWER

(KW)

208V 240V 480V 208V 240V 480V

12.5 35 33 15 45 40 20

PER LINE

Special

• Manometer

• Clamp on amp meter

• Spring force gauge, pull type with a minimum 30
pound full scale range (purchase locally)

• RTV sealant, 736 DOW silicone high temp (P/N

542133) or equivalent

1

RECOMMENDED CIRCUIT

PROTECTION

2

VC6ED

VC6EC

NOTES:

MODEL

VC4ES

VC4ED

VC4EC

VC6ES

VC6ED

VC6EC

NOTES:

1

Amperage values in the table are nominal. Tolerance is +5/-10%.

2

Complied in accordance with National Electric Code, ANSI/NFPA 70, latest edition

AMPERAGE - 1 PHASE/ 60HZ

TOTAL

POWER

(KW)

PER LINE

1

RECOMMENDED CIRCUIT

PROTECTION

2

12.5 60 52 26 80 70 35

1

Amperage values in the table are nominal. Tolerance is +5/-10%.

2

Complied in accordance with National Electric Code, ANSI/NFPA 70, latest edition.

Page 7 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

REMOVAL AND REPLACEMENT OF PARTS

COVERS AND PANELS

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

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.

NOTE: If the oven has a mechanical (KX type)
thermostat, it must be removed from the control panel
first, before removing the control panel.

Fig. 3

Fig. 1

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. 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 two screws near front of oven, which
secure the bottom front cover and control panel.

2. Remove the remaining seven screws securing
the right side panel.

Fig. 2

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.

F25105 Rev. C (1118) Page 8 of 75

3. Pull the right side panel out at the bottom then

4. Reverse the procedure to install.

Left Side Panel

Fig. 4

down to remove.

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

1. Remove the screws which secure the left side of
the top front cover, bottom front cover and control
panel.

2. Remove the seven screws securing the left side
panel.

Fig. 5

3. Pull the left side panel out at the bottom then
down to remove.

4. Reverse the procedure to install.

CONTROL PANEL COMPONENTS

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

Removable Components

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

Fig. 6

Page 9 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

Fig. 7

COMPONENT PANEL

COMPONENTS

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

Removable Components

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.

Fig. 8

3. Remove the component.

4. Reverse the procedure to install the replacement
component and check oven for proper operation.

F25105 Rev. C (1118) Page 10 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

Fig. 10

Fig. 11

5. Remove probe by pushing it through the oven
wall and into the control panel area.

Fig. 9

TEMPERATURE PROBE (SOLID

STATE CONTROL)

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

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 COVER AND PANELS.

2. Disconnect the probe leads from the solid state
temperature control.

3. Remove the racks and right rack support.

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.

When installing a 2nd generation guard, the tip of the
probe should be located near the center of the large
cutout, as shown in (fig link). The end with the wire
attached should be protected by the guard. It is
possible to damage the probe/wire with force from a
tray if probe is not protected properly.

Fig. 12

7. Adjust the temperature control as outlined under
SOLID STATE TEMPERATURE CONTROL
CALIBRATION in SERVICE PROCEDURES
AND ADJUSTMENTS.

4. Remove the probe guard or mounting clips.

1st Generation Guard Shown

Page 11 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

HEATING ELEMENTS Ending at

Serial Number 481916863

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

NOTE: Starting with production in October, 2001, the

top cavity panel will have 3/4" square holes for easier
element removal. Ovens manufactured prior to this
date have 1/2" round holes that sometimes make it
difficult to remove elements thru the cavity. A serial
number cut off will not be available. Follow the
procedures for element removal as outlined below.

Front Access

1. Remove the oven racks and rack supports.

2. Remove the "top" door seal from the oven.

3. Determine if the heating element to replace is on
the left or right side in the oven cavity. The
element locations from front to back are: Right
side - R1, R2 & R3; Left side - R4, R5 & R6.

A. Measure the current draw of the heating

elements as outlined under
ELEMENT TEST in SERVICE
PROCEDURES AND ADJUSTMENTS.

HEATING

A. If removing the right side panel, also remove

the probe guard or mounting clips.

B. Run the probe wire thru the panel opening

before lifting panel out.

5. From the element being replaced, remove the
hold down clamps, the mounting bracket screws
at the top, then remove the element.

Fig. 13

4. From inside the oven cavity, remove the
perforated panel from the same side of the
element being replaced.

NOTE: The mounting bracket is sealed with RTV
which may still hold the element after the screws are
removed. Also, in some cases, the ring terminal

F25105 Rev. C (1118) Page 12 of 75

Fig. 14

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

connected to the element may interfere with easy
removal. If access to the left side panel and/or the top
panel is available, see ALTERNATE ACCESS.

6. Disconnect the lead wires from the element.

7. Clean RTV residue from the mating surface
inside the oven, apply new high temperature RTV
to the heating element mounting bracket and
reverse procedure to install.

8. Check for proper operation.

Alternate Access

NOTE: If the heating element is not easy to remove

from inside the oven cavity, and access to the left side
panel and/or the top panel is available, this alternate
removal method may be used.

NOTE: On stacked ovens, if the bottom oven is being
serviced and the heating element to replace is on the
right side, the ovens must be unstacked to access the
heating element terminals through the top. Once
unstacked, follow the removal procedure below.

1. Perform steps 1 thru 4 under FRONT ACCESS.

2. If the element is on the left side:

HEATING ELEMENTS Starting at

Serial Number 481916864

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

1. Remove racks.

2. Remove RIGHT SIDE PANEL(S).

3. Remove nuts (1, Fig. 15) from element wiring
connections.

Use second wrench on nut (2, Fig. 15) behind terminal
when removing or installing to prevent element stud
from twisting and getting damaging.

A. the insulation at the top to expose the

element terminals.

B. Remove the lead wires from the element

being replaced. Proceed to step 4.

3. If the element is on the right side:

A. Remove the top panel and pull back the

insulation to expose the element terminals.

B. Remove the lead wires from the element

being replaced.

4. clamps holding the element vertical, the screw's
securing mounting bracket at the top, and then
remove the element.

NOTE: The mounting bracket is sealed with RTV
which may still hold the element after the screws are
removed.

5. Clean RTV residue from the mating surface
inside the oven, apply new high temperature RTV
to the heating element mounting bracket and
reverse procedure to install.

6. Check for proper operation.

Fig. 15

4. Remove top baffle.

Fig. 16

5. Remove side baffle.

Page 13 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

Fig. 19

8. Slide element mounting plate (1, Fig. 20) over to
release from cavity wall and remove elements
from oven.

Fig. 17

6. Remove element support brackets.

Fig. 18

7. Loosen all element mounting plate hex head
screws.

Fig. 20

9. Reverse procedure to install.

10. Verify operation.

F25105 Rev. C (1118) Page 14 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

BLOWER AND MOTOR Ending at

Serial Number 481916863

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

1. Take out the racks and rack supports.

2. Remove screws securing baffle panel and
remove the panel.

Fig. 22

5. Place a piece of cardboard on the bottom of the
oven cavity to protect its surface from any
damage during motor assembly removal.

Fig. 21

3. If replacing:

A. Blower Only - Loosen set screws on blower

hub and using a bearing puller, remove
blower from motor shaft.

1) Reverse procedure to install and adjust
blower position as outlined under
BLOWER ADJUSTMENT in SERVICE
PROCEDURES AND
ADJUSTMENTS.

B. Motor - perform step 3A and continue

procedure.

4. Remove the nuts that secure the motor mounting
plate to the rear wall.

6. Pull the motor assembly into the oven cavity and
place it on the cardboard.

7. Remove the junction box cover from the motor,
disconnect lead wires and remove the conduit.

8. Remove motor mounting bolts and flat washers
then lift the motor from the mounting plate.

9. Position the replacement motor on the motor
mounting plate and install mounting bolts and
washers. Hand tighten mounting bolts only.

Fig. 23

10. Reconnect lead wires at the motor, replace
conduit and junction box cover.

NOTE: Check data plate on motor for wiring
schematic. The motor must rotate clockwise when
viewed from the shaft end.

Page 15 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

Fig. 24

11. Slide blower onto motor shaft until hub is flush
with end of shaft then tighten set screws.

12. Adjust motor position until blower is parallel to
motor mounting plate as outlined under
BLOWER ADJUSTMENT in SERVICE
PROCEDURES AND ADJUSTMENTS.

13. Position motor mounting plate on the rear wall
and secure with nuts and washers.

14. Replace the baffle panel.

15. Remove cardboard from the bottom of the oven
cavity.

16. Check oven for proper operation then replace
rack guides and racks

BLOWER AND MOTOR Starting at

Serial Number 481916864

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

1. Remove HEATING ELEMENTS.

Fig. 25

3. Pinch cord grip together to remove from rear
panel.

2. Disconnect motor harness (1, Fig. 25).

4. Push motor wiring harness/cord out hole in rear

5. Remove blower baffle screws (2, Fig. 27) if

F25105 Rev. C (1118) Page 16 of 75

Fig. 26

panel.

applicable.

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

Fig. 29

11. Reverse procedure to install.

12. Verify operation.

Fig. 27

6. Remove motor mounting plate nuts (1, Fig. 27).

7. Place a piece of cardboard on bottom of oven
cavity to protect its surface from any damage
during motor assembly removal.

8. Pull motor assembly into oven cavity and place
on cardboard.

9. Remove motor mounting bolts and washers and
lift motor off mounting plate.

DOOR SWITCH

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

1. Remove the top front cover as outlined under
COVERS AND PANELS.

2. Disconnect the lead wires to the door switch.

3. Remove the switch.

Fig. 28

NOTE: Motor graphics are shown with motor

installed.

10. Remove drip pan from motor and install onto
replacement motor.

Fig. 30

4. Reverse procedure to install the replacement
switch and check for proper adjustment as
outlined under DOOR SWITCH ADJUSTMENT
in SERVICE PROCEDURES AND
ADJUSTMENTS.

Page 17 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

DOOR WINDOW

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

1. Remove the screws at the top and bottom of
door.

Fig. 31

2. Independent doors:

A. Remove the door handle then remove the

outer door panel.

B. Lift out the inner door panel and window

assembly.

NOTE: Left door only - remove door seal from the
inside edge of the door.

3. Simultaneous doors:

A. If replacing window on the left door, remove

the handle from the front of the door then
remove door seal from the inside edge of the
door.

1) Lift out the inner door panel and
window assembly.

2) If replacing window on the right door,
remove the screws along the inside
edge (if applicable) of the door then
remove the inner door panel and
window assembly.

4. Remove the screws securing the window "tabs"
to the door bracket and lift the window assembly
out from the door frame.

Fig. 32

5. Reverse procedure to install the replacement
window.

OVEN DOORS AND BEARINGS

(INDEPENDENT DOORS) Ending at

Serial Number 481916782

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

1. Remove the top front cover and bottom front
cover as outlined under COVERS AND
PANELS.

2. Remove the door switch lever.

F25105 Rev. C (1118) Page 18 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

8. Reverse procedure to install door assembly and
check for proper adjustment as outlined under
DOOR ADJUSTMENT and DOOR SWITCH
ADJUSTMENT in SERVICE PROCEDURES
AND ADJUSTMENTS.

OVEN DOORS (INDEPENDENT

DOORS) Starting at Serial Number

481916783

Fig. 33

3. Remove the lower door seal strip to expose the
mounting screws of the door assembly.

4. Remove the two (2) lower sill bolts by the lower
door shaft and the four (4) counter-sunk screws
from the lower sill.

Fig. 34

NOTE: The door assembly is heavy and will drop

down once the last screw is removed. If removing door
assembly with-out assistance, use caution.

5. Tilt the top of the door slightly forward and lift the
door up until the bottom of the door shaft clears
the opening in the sill.

6. Lay the door flat to prevent damage.

7. The top and bottom bearings are now accessible
for inspection and/or replacement if needed.

A. If bearings are ok, proceed to step 8.

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

1. Remove TOP FRONT COVER.

2. If servicing right side door, remove door switch
lever (1, Fig. 36).

Fig. 36

3. While supporting door, remove hex bolts holding
upper bearing retainer (1, Fig. 37 ) and upper
shaft bracket (2, Fig. 37).

B. If replacing the top bearing, remove the top

bearing retainer and top bearing.

Fig. 35

C. If replacing the bottom bearing, remove it

from the door shaft or the lower sill opening.

Page 19 of 75 F25105 Rev. C (1118)

Fig. 37

4. Lift door off lower shaft bracket.

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

A. Remove the two (2) lower sill bolts by the

lower door shaft and the four (4) counter-

Lay door on flat protective surface to service.

5. Reverse procedure to install.

6. Perform DOOR ADJUSTMENT if servicing right
side door.

sunk screws from the lower sill.

OVEN DOORS (SIMULTANEOUS

DOORS) Ending at Serial Number

481916783

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

Assembly Removal

1. Remove the top front cover and bottom front
cover as outlined under COVERS AND
PANELS.

2. Remove the door switch lever.

NOTE: The door assembly is heavy and will drop
down once the last screw is removed. If removing door
assembly with-out assistance, use caution.

5. Lift up on the door assembly and swing the right
side out then move the assembly to the left to
clear the slots in the upper door sill.

6. Lay the door assembly on a flat cushioned
surface for disassembly.

7. Reverse procedure to install door assembly and
check for proper adjustment as outlined under
DOOR ADJUSTMENT, DOOR CHAIN
ADJUSTMENT (SIMULTANEOUS DOORS) and
DOOR SWITCH ADJUSTMENT in SERVICE
PROCEDURES AND ADJUSTMENTS.

Fig. 40

Fig. 38

3. Remove the top bearing retainers and top
bearings.

Disassembly

1. Remove the door assembly as outlined in OVEN
DOORS (SIMULTANEOUS) under ASSEMBLY
REMOVAL.

2. Remove the door chain by loosening one of the
turnbuckles.

3. Loosen the set screw on the sprocket of door
being replaced.

4. Drive out the spirol pin from the sprocket of door
being replaced.

5. Remove the door from lower sill bearings and
sprocket.

Fig. 39

4. Remove the lower door seal strip to expose the
mounting screws of the door assembly.

F25105 Rev. C (1118) Page 20 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

Fig. 41

A. Door assembly parts are now accessible for

inspection and/or replacement if necessary.

6. Reverse procedure to re-assemble the door
assembly parts and check for proper adjustment
as outlined under
(SIMULTANEOUS DOORS) in SERVICE
PROCEDURES AND ADJUSTMENTS.

DOOR CHAIN ADJUSTMENT

OVEN DOORS (SIMULTANEOUS

DOORS) Starting at Serial Number

481916783

1. Remove TOP FRONT COVER and BOTTOM
FRONT COVER.

2. Remove door switch lever.

Fig. 43

4. Loosen the set screw on the sprocket of door
being replaced (

5. Drive out the spiral pin from the sprocket of door
being replaced (

6. While supporting door, remove hex head bolts
holding upper bearing retainer (1, Fig. 44) and
upper shaft bracket (2, Fig. 44).

Fig. 43).

Fig. 43).

Fig. 42

3. Remove door chain by loosening one of the
turnbuckles (Fig. 43).

Fig. 44

7. Remove door(s) from lower sill bearings and
sprocket Fig. 43.

Lay door on flat protective surface to service.

8. Reverse procedure to install.

Verify spacers are reassembled as found when
removed.

Page 21 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

9. Perform door adjustments.

A. DOOR ADJUSTMENT .

B. DOOR CHAIN ADJUSTMENT

(SIMULATANEOUS DOORS) .

C. DOOR SWITCH ADJUSTMENT .

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

ROLLER LATCH ASSEMBLY

(INDEPENDENT DOORS)

1. Remove the top front cover as outlined under
COVERS AND PANELS.

NOTE: For units with serial number starting with 48
made after 8/12/07 and serial number starting with 54
made after 8/26/07.

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

1. Remove the screws that attach roller latch
assembly to door.

Fig. 45

2. Reverse procedure to install.

2. Remove the catch roller assembly.

Fig. 46

3. Reverse procedure to install.

4. Adjust the catch roller as outlined under DOOR
CATCH (ROLLER) ADJUSTMENT
(INDEPENDENT DOORS) in SERVICE
PROCEDURES AND ADJUSTMENTS.

DOOR CATCH ROLLER ASSEMBLY

MECHANICAL (KX) THERMOSTAT

(INDEPENDENT DOORS)

NOTE: For units with serial number starting with 48

made before 8/13/07 and serial number starting with
54 made before 8/27/07.

1. Remove the racks and right rack support.

2. Remove the thermostat knob and mounting

F25105 Rev. C (1118) Page 22 of 75

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

screws from the control panel and then remove
the control panel.

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

3. Remove the probe guard from the oven cavity
wall.

Fig. 47

NOTE: When installing probe guard, the probe should

not extend beyond the guard.

4. Remove the thermostat bulb from the oven cavity
by pushing it through the oven 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.

5. Reverse the procedure to install.

6. Adjust the thermostat as outlined under
MECHANICAL (KX) THERMOSTAT
CALIBRATION in SERVICE PROCEDURES
AND ADJUSTMENTS.

HIGH LIMIT THERMOSTAT

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

1. Take out racks from the oven.

2. Remove the high limit thermostat cover/mounting
plate from inside the oven cavity at the top.

Fig. 48

3. Disconnect lead wires from high limit thermostat
then remove high limit thermostat from cover/
mounting plate.

Fig. 49

NOTE: Remove the old RTV sealer from the cover

and mating surfaces inside the oven cavity and apply
new high temperature RTV sealer before installing.

4. Reverse procedure to install.

INTERIOR LIGHTS (Rear Mounted,

Round)

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

Lamp

1. Remove racks.

2. Unscrew glass lens for the light being replaced
then unscrew bulb.

Page 23 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

NOTE: Use a cloth when handling bulb so you do not
leave fingerprints on bulb.

Fig. 50

3. Replace bulb then reverse procedure to install.

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

Lamp Assembly

1. Remove lens and bulb.

2. Remove springs from retaining tabs (2 places) on
the socket.

INTERIOR LIGHTS (Side Mounted,

Square)

Bulb Replacement

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

1. Remove racks and right-side hand rack guide.

2. Pull lamp cover off.

3. Grasp lamp using a clean cloth and remove from
lamp assembly.

Fig. 51

3. Depress retaining tabs and pull socket out from
the oven, far enough to disconnect lead wires.

4. Remove socket from the oven.

5. Attach lead wires to the replacement socket.

6. Insert socket into the hole in oven and push until
socket is held in place by retaining tabs.

7. Install light bulb and lens.

8. Check for proper operation.

F25105 Rev. C (1118) Page 24 of 75

4. Reverse procedure to install new bulb.

NOTE: Verify gasket (1, Fig. 53) is flat on lamp cover
and not damaged.

Fig. 52

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

Fig. 53

Lamp Assembly Replacement

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

1. Remove racks.

2. Remove BULB if reusing.

3. Lift right side rack guide off oven cavity.

4. Pull lamp cover off from the top or bottom.

5. Insert narrow blade screwdriver into tab and
bend out to release. Repeat with second tab.

Fig. 54

6. Pull lamp housing out of oven cavity.

7. Disconnect wires.

Fig. 55

8. Reverse procedure to install.

Page 25 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - REMOVAL AND REPLACEMENT OF PARTS

NOTE: Verify gasket (1, Fig. 56) is flat on lamp cover
and not damaged.

Fig. 56

COOLING FAN

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

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. removing wire nuts.

3. Remove the screws securing the air deflector to
the fan then loosen the tab screw holding the fan
to the component panel. Rotate the tab so that
the fan will clear and remove the fan.

Fig. 57

4. Reverse the procedure to install the replacement
fan and check for proper operation.

NOTE: The fan must be installed so air is pulled from
outside the rear of the oven and blown into the control
area. The arrow on the fan body indicates "air flow"
direction and should be pointing toward the controls.

NOTE: Ensure fan is seated "squarely" against the
air tube and the oven bottom.

NOTE: The air deflector should be angled upwards
at approximately 30 degrees to properly direct the air
flow.

F25105 Rev. C (1118) Page 26 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE PROCEDURES AND ADJUSTMENTS

SERVICE PROCEDURES AND ADJUSTMENTS

Certain procedures in this section require electrical test or measurements while power is
applied to the machine. Exercise extreme caution at all times and follow Arc Flash procedures.
If test points are not easily accessible, disconnect power and follow Lockout/Tagout
procedures, attach test equipment and reapply power to test.

SOLID STATE TEMPERATURE

CONTROL CALIBRATION

UNITS BEFORE JUNE 2013

1. Place a thermocouple in geometric center of
oven cavity.

2. Set ON-OFF-COOL DOWN switch to ON.

3. Set temperature control dial to 350°F.

4. Allow oven temperature to stabilize (normally 3
cycles).

5. Record temperature at which Heat lamp goes
OFF and comes ON for at least two complete
heating cycles.

6. Calculate differential by subtracting temperature
indicated when lamp goes out from temperature
indicated when lamp comes on.

Differential = Heat lamp OFF - Heat lamp ON

Example: 360° (lamp off) - 340° (lamp on) =
20°

A. Calculated differential should be less than

20°F.

1) If differential is less than 20°F,
temperature control circuit is
functioning properly.

a. Proceed to Step 7.

7. Calculate average temperature by adding
temperature indicated when lamp goes out to
temperature indicated when lamp comes on and
dividing this answer by 2.

[Temp. (lamp off) + Temp. (lamp on)] ÷ 2 =
Average Temp. Example: (360° + 340°) ÷ 2 =
350°

A. If average temperature is less than 10°F

from dial setting, thermostat is properly
calibrated.

B. If average temperature is more than 10°F

from dial setting, thermostat calibration
must be adjusted.

1) Loosen temperature control knob set
screw and remove knob from stem.

2) Loosen temperature control mounting
screws only enough to rotate control.

a. Place thumb and forefinger on

mounting screw heads, apply
pressure and slightly rotate screw
heads (body of control) in slot.
Rotate clockwise to increase
temperature and
counterclockwise to decrease.

b. Center stem (Fig. 58) in opening

and re-tighten temperature
control mounting screws.

2) If differential is more than 20°F:

a. Check temperature probe as

outlined under TEMPERATURE
PROBE TEST (SOLID STATE
CONTROL).

b. If probe is functioning properly

then temperature control is
malfunctioning.

a) Install a replacement

temperature control and
check calibration.

Page 27 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE PROCEDURES AND ADJUSTMENTS

6. Calculate differential by subtracting temperature
indicated when lamp goes out from temperature
indicated when lamp comes on.

Differential = Heat lamp OFF - Heat lamp ON

Example: 360° (lamp off) - 340° (lamp on) =
20°

A. Calculated differential should be less than

20°F.

1) If differential is less than 20°F,
temperature control circuit is
functioning properly.

a. Proceed to Step 7.

2) If differential is more than 20°F:

a. Check temperature probe as

outlined under TEMPERATURE
PROBE TEST (SOLID STATE
CONTROL).

Fig. 58

c. Replace knob and re-tighten set

screw.

d. Rotate knob to lowest

temperature setting then back to
350°F.

e. Repeat average temperature

calculation in

NOTE: Allow oven to cycle at least two times between
adjustments before performing calculation.

a) If average temperature still

differs more than 10°F from
dial setting, adjust
thermostat calibration until
average temperature is
within tolerance.

C. If above adjustment cannot be obtained,

replace temperature control and check
calibration.

UNITS AFTER JUNE 2013

1. Place a thermocouple in geometric center of
oven cavity.

2. Set ON-OFF-COOL DOWN switch to ON.

3. Set temperature control dial to 350°F.

4. Allow oven temperature to stabilize (normally 3
cycles).

Step 7.

7. Calculate average temperature by adding
temperature indicated when lamp goes out to
temperature indicated when lamp comes on and
dividing this answer by 2.

[Temp. (lamp off) + Temp. (lamp on)] ÷ 2 =
Average Temp. Example: (360° + 340°) ÷ 2 =
350°

A. If average temperature is less than 10°F

B. If average temperature is more than 10°F

NOTE: If no access hole exists in overlay, you may
carefully create one.

b. If probe is functioning properly

then temperature control is
malfunctioning.

a) Install a replacement

temperature control and
check calibration.

from dial setting, thermostat is properly
calibrated.

from dial setting, thermostat calibration
must be adjusted.

1) Loosen temperature control knob set
screw and remove knob from stem.

2) Access adjustment potentiometer
located at 3 o'clock position (Fig. 59).

5. Record temperature at which Heat lamp goes
OFF and comes ON for at least two complete
heating cycles.

F25105 Rev. C (1118) Page 28 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE PROCEDURES AND ADJUSTMENTS

6. Calculate the differential by subtracting the
temperature indicated when heat lamp goes out
from temperature indicated when heat lamp
comes on.

Differential - Heat lamp OFF - Heat lamp ON.
Example: 360° (lamp off) - 340° (lamp on) = 20°

A. The differential calculated should be less

than 30°F.

1) If the differential is 30°F or less, the
thermostat is functioning properly. a.
Proceed to step 7.

a. Proceed to step 7.

2) If the differential is more than 30°F, the
thermostat is malfunctioning.

a. Install a replacement thermostat

Fig. 59

a. Turn clockwise to increase,

counterclockwise to decrease

temperature

b. Repeat average temperature

calculation in Step 7.

NOTE: Allow oven to cycle at least two times between
adjustments before performing calculation.

a) If average temperature still

differs more than 10°F from
dial setting, adjust
thermostat calibration until
average temperature is
within tolerance.

7. Calculate the average temperature by adding the
temperature indicated when the heat lamp goes
out to the temperature indicated when the heat
lamp comes on and dividing this answer by 2.

[Temp. (lamp off) +Temp. (lamp on)] + 2 =
Average Temp. Example: 360° + 340° +2 = 350°

A. If the average temperature is 15°F or less

from the dial setting, the thermostat is
properly calibrated.

B. If the average temperature is more than

15°F of the dial setting, the thermostat
calibration must be adjusted.

1) Remove the thermostat knob.

and check calibration.

C. If above adjustment cannot be obtained,

replace temperature control and check
calibration.

MECHANICAL (KX) THERMOSTAT

CALIBRATION

1. Place a thermocouple in the geometric center of
the oven cavity.

2. Set the power switch to ON.

3. Set the thermostat dial to 350°F.

4. Allow the oven temperature to stabilize (normally
3 cycles).

5. Record the temperature when the thermostat
cycles OFF and ON for at least three complete
cycles.

Page 29 of 75 F25105 Rev. C (1118)

2) Hold the thermostat shaft and turn the
inner set screw clockwise to decrease
temperature or counterclockwise to
increase temperature (¼ turn = 35°F).

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE PROCEDURES AND ADJUSTMENTS

SOLID STATE TEMPERATURE

CONTROL TEST

Certain procedures in this section
require electrical test or
measurements while power is
applied to the machine. Exercise
extreme caution at all times and
follow Arc Flash procedures. If test
points are not easily accessible,
disconnect power and follow
Lockout/Tagout procedures, attach
test equipment and reapply power to
test.

1. Remove the RIGHT SIDE PANEL.

NOTE: If right side panel is not accessible, this
component can be serviced by removing
PANEL.

CONTROL

Fig. 60

8. Replace the knob and verify the setting is still at
350°F.

9. Repeat step 7 until the average temperature is
within tolerance.

NOTE: Allow the oven to cycle at least two times
between adjustments before performing the
calculation.

A. After the final adjustment is made and the

average temperature is within tolerance,
remove the knob and apply a nonpermanent
type sealer around the head of the set screw

10. If the above adjustment cannot be obtained:

A. Turn the power switch OFF.

2. Place a thermocouple in the geometric center of
the oven cavity.

NOTE: Oven temperature must be below 450°F.

NOTE: If oven is equipped with "Cook and Hold"

option, set to Cook (normal cooking) before
continuing.

3. Set the temperature control to the maximum
setting.

4. Check machine data plate for correct voltage to
oven. Refer to diagram below for proper terminal
locations and voltages before checking the
control. Use the correct terminals for the
corresponding voltage.

5. Turn the power switch to ON.

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

B. Install a replacement thermostat and check

calibration.

F25105 Rev. C (1118) Page 30 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE PROCEDURES AND ADJUSTMENTS

8. Set the temperature control to the minimum
setting.

NOTE: Oven temperature must be above 300°F.

9. Check for zero (0) volts AC across terminals
OUTPUT RELAY terminal (right side) to 120 VAC
or OUTPUT RELAY terminal (right side) to
208-240 VAC for no output from the internal
relay.

A. If correct, temperature control is functioning

properly.

B. If incorrect, check temperature probe as

outlined under TEMPERTURE PROBE
TEST (SOLID STATE CONTROL).

1) If temperature probe is OK:

Fig. 61

6. Check for proper voltage across terminals COM
AC to 120VAC or COM AC to 208-240VAC for
power to the control.

A. If correct, proceed to step 7.

B. If incorrect, problem is not with the

temperature control. See
TROUBLESHOOTING.

7. Check relay voltages on the board:

A. For 120VAC controls - check across

OUTPUT RELAY terminal (left side) to 120
VAC terminal for input to the internal relay.
Check across OUTPUT RELAY terminal
(right side) to 120 VAC for output from the
internal relay.

B. For 208-240VAC controls - check across

OUTPUT RELAY terminal (left side) to
208-240 VAC terminal for input to the
internal relay. Check across OUTPUT
RELAY terminal (right side) to 208-240 VAC
for output from the internal relay.

1) If input voltage to the internal relay is
correct, proceed to step 8. If input
voltage to the internal relay is not
present, problem is not with the
temperature control. See
TROUBLESHOOTING.

a. Turn the power switch OFF.

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

b. Replace the temperature control

and check calibration as outlined
under SOLID STATE
TEMPERATURE CONTROL
CALIBRATION.

TEMPERATURE PROBE TEST

(SOLID STATE CONTROL)

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

NOTE: The temperature probe used in conjunction

with the Solid State Temperature control is an RTD
(resistance temperature detector) of the Thermistor
type. As temperature increases the resistance value
decreases.

2) If output voltage from the internal relay
is correct proceed to step 8. If output
voltage from the internal relay is not
correct, check temperature probe as
outlined under TEMPERATURE
PROBE TEST (SOLID STATE
CONTROL).

Page 31 of 75 F25105 Rev. C (1118)

1. Remove the right side panel as outlined under
COVERS AND PANELS in REMOVAL AND
REPLACEMENT OF PARTS.

NOTE: If right side panel is not accessible, this
component can be serviced by removing the control
panel as outlined underCOVERS AND PANELS.

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE PROCEDURES AND ADJUSTMENTS

2. Place a shielded thermocouple in the geometric
center of the oven cavity and determine the
temperature in the oven cavity.

3. Remove the probe lead wires from the solid state
temperature control.

4. Test the probe with an ohmmeter.

A. If the measured resistance values are inside

the given tolerance then the probe is
functioning properly.

B. If the measured resistance values are

outside the given tolerance then replace the
probe and retest.

1) Check oven for proper operation.

HEATING ELEMENT TEST

Disconnect the electrical power to the machine and follow lockout / tagout procedures. There
may be multiple circuits. Be sure all circuits are disconnected.

5. Reverse procedure to install.

TEMP (°F) OHMS * TEMP (°F) OHMS *

77 90,000 360 822

240 4,077 380 656

260 3,016 400 529

280 2,266 425 424

300 1,726 450 334

320 1,332 475 266

340 1,041

* Resistance in ohms ± 10%

1. Turn the power switch ON and set the oven temperature control to the highest setting.

2. Measure the voltage at the heating element terminals and verify it against the data plate voltage.

A. If voltage is incorrect, find the source of the problem.

B. If voltage is correct, check current draw (amps) through the heating element lead wires.

NOTE: This method is preferred over a resistance check when a clamp on type amp meter is available.

1) If current draw is correct then heating element is functioning properly.

2) If current draw is not correct, turn the power switch OFF and disconnect the electrical supply to the
oven.

a. Replace HEATING ELEMENTS Ending at Serial Number 481916863.

C. If unable to check current draw, a resistance check may indicate a malfunctioning element.

1) Turn the power switch OFF and disconnect the electrical supply to the oven.

2) Remove the lead wires from the heating element and check resistance (ohms).

3. Check for proper operation.

SIDE MOUNTED ELEMENTS

VOLTAGE AMPS PER ELEMENT KW PER ELEMENT OHMS PER ELEMENT

208 (red) 9.6 2 21.6

240 (blue) 8.3 2 28.8

480 (yellow) 4.1 2 115.2

F25105 Rev. C (1118) Page 32 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE PROCEDURES AND ADJUSTMENTS

SIDE MOUNTED ELEMENTS

VOLTAGE AMPS PER ELEMENT KW PER ELEMENT OHMS PER ELEMENT

1. Values in the table are nominal. Tolerance is +5/-10%.

NOTES:

VOLTAGE AMPS PER ELEMENT KW PER ELEMENT OHMS PER ELEMENT

208 19.2 4 10.8

240 16.6 4 14.4

480 8.3 4 57.6

NOTES:

2. Voltage values are @ 60HZ

3. Resistance values (ohms) are @ room temperature.

4. Color coding located on the one corner of mounting bracket.

REAR MOUNTED ELEMENTS

1. Values in the table are nominal. Tolerance is +5/-10%.

2. Voltage values are @ 60HZ

3. Resistance values (ohms) are @ room temperature.

4. Replaced as a set, check individually.

BLOWER ADJUSTMENT

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

1. Remove the blower motor and mounting
assembly by following steps 1 through 7 as
outlined under BLOWER AND MOTOR in
REMOVAL AND REPLACEMENT OF PARTS.

2. Loosen the motor mounting bolts.

3. Adjust the motor position until the blower is
parallel to and 1/4 inch away from the motor
mounting plate. Check for squareness of the
blower to the motor mounting plate at the top,
bottom, left and right of the blower.

A. If the blower is square then tighten motor

mounting bolts and proceed to step 4.

B. If the blower is not square continue

adjusting until proper spacing is achieved
then tighten motor mounting bolts

NOTE: If necessary, place shims between motor and
frame.

Fig. 62

4. Reverse the procedure to install.

DOOR ADJUSTMENT

1. Check the doors to make sure they have a .125
(1/8") gap between them and that the vertical
edge of the door is parallel to the vertical door
seal. If the doors are not positioned in this
manner, adjust the doors as described.

Page 33 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE PROCEDURES AND ADJUSTMENTS

Fig. 64

Figure shown below (Left Side) is starting at
Serial Number 481916783.

Fig. 63

2. Remove the TOP FRONT COVER.

3. Loosen the screws/bolts that secure the upper
door brackets just enough to allow door
movement.

Figure Shown below (Left Side) is ending at
Serial Number 481916782.

Fig. 65

4. Move the door until proper alignment is achieved
then tighten the screws/bolts on the upper door
bearing hardware.

5. Repeat Step 3 and Step 4 on the opposite door,
if necessary.

6. Install TOP FRONT COVER.

DOOR STRIKE ADJUSTMENT

(INDEPENDENT DOORS)

NOTE: For units with serial number starting with 48

made after 8/12/07 and serial number starting with 54
made after 8/26/07.

F25105 Rev. C (1118) Page 34 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE PROCEDURES AND ADJUSTMENTS

DOOR CATCH ROLLER

ADJUSTMENT (INDEPENDENT

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

1. Remove top front cover as outline under
COVERS AND PANELS in REMOVAL AND
REPLACEMENT OF PARTS.

NOTE: For units with serial number starting with 48
made before 8/13/07 and serial number starting with
54 made before 8/27/07.

DOORS)

2. Open the doors and inspect door strike for proper
shape.

A. Replace if bent. Do not bend strike plate.

B. If adjustment is necessary, loosen

fasteners, close doors and insure contact
between door inner surface and upper
horizontal seal. Slide door strike plate until
contact with roller latch is made. Tighten
strike plate fasteners

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

1. Remove the top front cover as outline under
COVERS AND PANELS in REMOVAL AND
REPLACEMENT OF PARTS.

2. Open the doors and inspect the door strike for
proper shape.

Fig. 66

3. Open and close the doors several times while
observing the roller latch and strike plate
operation.

A. Replace roller latch if malfunctioning as

outlined under ROLLER LATCH
ASSEMBLY (INDEPENDENT DOORS)
and adjust as outlined in this procedure.

4. Each oven door should open with a force of 8 to
25 pounds when pulled at the handle. The
adjustments must allow the doors to remain
closed during normal operation and allow
opening without exertion by the user.

Page 35 of 75 F25105 Rev. C (1118)

Fig. 67

A. Replace if bent and adjust as outlined in this

procedure.

3. Open and close the doors several times while
observing the catch roller operation.

A. Replace if malfunctioning and adjust as

outlined in this procedure.

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE PROCEDURES AND ADJUSTMENTS

NOTE: Shims may be required under the door strike
to raise it, before the proper door tension adjustment
can be set.

4. Apply lubricant around the spring. See
LUBRICATION under GENERAL.

5. Close the doors and check them for proper
alignment.

A. Doors should be centered and parallel at the

top and bottom, in the oven cavity opening.
See DOOR ADJUSTMENT.

6. With the doors closed, observe the position of the
catch roller "ball" in relation to the door strike.

A. Ensure the catch roller "ball" is centered (left

to right) to the door strike.

1) Adjust alignment, if necessary.

B. Open the right side door and view the left

side door catch roller and strike. Ensure the
door catch roller "ball" is resting upon the
angular surface of the door strike. Repeat
on the opposite door.

DOOR SWITCH ADJUSTMENT

Fig. 68

1) If adjustment is necessary, loosen the
mounting screws then slide the door
strike from "front to back" until the roller
rests upon the angular surface of the
door strike. Tighten screws and check
operation.

2) If proper adjustment cannot be
achieved, add shims beneath the door
strike. Repeat step 6 thru this step.

NOTE: DO NOT BEND THE DOOR STRIKE.

7. Each oven door should open with a force of 8 to
25 pounds when pulled at the handle. See
TOOLS under GENERAL.

A. Adjust catch roller tension as follows:

1) Turn the set screw inside the catch
assembly housing clockwise to
increase tension on the catch roller and
counterclockwise to decrease tension
on the catch roller.

NOTE: The amount of tension on the catch roller
determines the opening force of the door.

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

1. Remove the top front cover as outlined under
COVERS AND PANELS in REMOVAL AND
REPLACEMENT OF PARTS.

2. Door operation:

A. Independent doors - The switch actuator

should be operated by the switch lever when
the right door is between 1" and 1 1/2" from
being closed.

B. Simultaneous doors - The switch actuator

should be operated by the switch lever when
the right door is 1/2" from being closed.

3. If adjustment is necessary, bend the switch
actuator to obtain the proper setting.

2) Continue adjustment until proper door
operation is achieved.

F25105 Rev. C (1118) Page 36 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE PROCEDURES AND ADJUSTMENTS

Fig. 69

4. Install the top front cover.

5. Apply power to the oven and check for proper
operation.

4. If right door does not lead the left door in closing:

Fig. 70

DOOR CHAIN ADJUSTMENT

(SIMULATANEOUS DOORS)

Introduction

When the oven doors are in proper adjustment,
as the doors come together, the right door will
lead the left door in closing by about 1/4 inch. The
doors will feel like they are self closing the last
1/2 inch of travel.

Procedure

1. Remove the lower sill cover as outline under
COVERS AND PANELS in REMOVAL AND
REPLACEMENT OF PARTS.

2. Close doors and check door chain for factory
setting.

A. Turnbuckles should be 5 to 5 1/2 inches

apart.

B. Short eye bolt should be connected to the

end of the chain that goes to the front of the
sprocket.

C. 2 links of the chain should not be engaged

at the rear of the sprocket.

D. Chain must be tight enough that the doors

move simultaneously when opened or
closed.

E. When the doors are opened, the

turnbuckles will move away from each other.

F. The stop cable must be positioned where it

moves freely and does not get pinched.

3. Position door chain assembly to factory setting if
the conditions in step 2 are not met.

A. Loosen locknuts on both turnbuckles.

B. Loosen left turnbuckle.

C. Tighten right turnbuckle.

D. Tighten locknuts on both turnbuckles.

5. If the right door leads the left door by more than
3/8 inch:

A. Loosen locknuts on both turnbuckles.

B. Loosen right turnbuckle.

C. Tighten left turnbuckle.

D. Tighten locknuts on both turnbuckles.

6. Check door for proper operation.

NOTE: The locknuts must be tight during testing or
the adjustment will not hold.

A. If doors do not close properly, repeat step 4,

5 and 6.

B. If doors operate properly, continue to step 7.

7. Install the lower front cover.

COMPUTER CONTROL

Operation

Refer to the Instructions Manual F31159 for
specific operating instructions.

Setup Mode

NOTE: Use the setup mode to verify that the control

is configured to the factory settings which result in the
proper operation of the oven. If the CAL1 parameter
is other than zero, determine if it is still needed before
resetting to zero. See COMPUTER CONTROL
TEMPERATURE CALIBRATION.

Page 37 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE PROCEDURES AND ADJUSTMENTS

If the oven is not heating or displaying the proper
temperature, the temperature probe may be

Changing the C_F, InP1, rL1 & rH1 parameters will
default all menus to the factory settings.

1. Use this key sequence to access the setup mode.

Up arrow; Rack 1; Temperature; Temperature;
Down arrow; Rack 1

malfunctioning. Determine if the probe is good or
causing the operational problem. Temporarily,
disconnect the existing probe lead wires from the
computer control and connect the lead wires from
a known good "J" type thermocouple. Secure the
sensing end of the thermocouple near the probe.

Turn the power switch ON and set the dial to
350°F.

Fig. 71

2. Once in the setup mode the display will alternate
between the parameter and programmed data.

• To change data to the factory setting, use

the arrow keys.

• To select the next parameter, press the

Rack 1 key.

• After the last Parameter and Data is viewed,

press the Rack 1 key a final time to exit the
setup mode and return to operations mode.
The current set point temperature will be
displayed.

• After 1 minute of no key activations, the

control will return to operation mode.

3. Listed are the parameters and data you should
find.

ALTERNATING

MENU

Celsius_Fahrenheit C_F F

Guard Band gb 4000

Temperature
Compensation

Input Type 1 InP1 J

Range Low 1 rL1 75

Range Hight 1 rH1 500

Hysteresis HYS1 3

Calibration Offset CAL1 0

Exit Setup Mode and
returen to Operation
Mode.

Probe Test

Set point temperature is
displayed or if call for heat,
dashers(---) displayed.

ON DISPLAY

PARAMETER DATA

tcnP OFF

If the oven reaches the set temperature and
cycles with the temporary thermocouple, then the
existing probe is malfunctioning. Replace
temperature probe with the correct part and
check for proper operation.

Solid State Relay Test

The solid state relays "SSR1 or SSR2" supply
power to the blower motor "high" or "low" fan
speed terminals when the SSR is energized by
the output voltage from the computer.

To test solid state relay "SSR1" (high fan speed),
the computer control should be in the "Normal
Cooking Mode". To test solid state relay "SSR2"
(low fan speed), the computer control should be
in the "Roast & Hold Mode".

Fig. 72

1. Remove the right side panel as outlined under
COVERS AND PANELS.

2. Turn the power switch ON.

F25105 Rev. C (1118) Page 38 of 75

A. If the blower motor comes on, the SSR is

functioning properly.

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE PROCEDURES AND ADJUSTMENTS

B. If the blower motor does not come on,

proceed to step 3.

3. Check for +5 VDC on the input side of SSR
(terminals 3 & 4).

A. If +5 VDC is present, continue to step 4.

B. If no voltage is present, computer control is

not functioning properly.

4. Check for proper input voltage on the load side
of SSR terminal 1 and the power connection on
the other side of the supply.

A. On 208 & 240 volt ovens, the supply

connection is on the terminal block (L2 for
single phase, L3 for three phase). The
measured voltage should be identical to the
supply.

B. On 480 volt ovens, the supply connection is

on the secondary side of the 480V
transformer, terminal X4 (wire # 79).

The measured voltage should be 240 volts.

5. If input voltage is correct on the load side of SSR
terminal 1, proceed to step 6.

A. If the set point temperature is 350°F,

proceed to step 4.

B. If the set point temperature is other than

350°F, proceed to step 3 to change the
temperature.

3. Press the set key then temperature key to enter
the temperature set mode.

A. The display will alternate between the term

"StPt" (set point) and the current oven
temperature setting.

B. Press the up or down arrow keys to make

the proper selection.

C. Press the set key again to save the change

and exit the temperature set mode.

4. Allow the oven temperature to stabilize (normally
3 cycles).

5. Compare the controls set point temperature to
the thermocouple meter reading when the heat
light goes out.

A. A temperature variance more than 5°F

indicates an adjustment is needed.

A. If input voltage is not correct, find the source

of the problem.

6. Check output voltage on the load side of SSR
terminal 2.

A. If voltage is correct, SSR is functioning

properly.

B. If no voltage is present on the load side of

SSR terminal 2, the SSR is not functioning
properly.

7. Turn the power switch OFF.

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

8. Replace the SSR and check for proper operation.

COMPUTER CONTROL

TEMPERATURE CALIBRATION

1) To make the adjustment, proceed to
step 6.

2) If temperature variance is less than
5°F, computer control is functioning
properly.

6. Enter the setup mode as outlined in SETUP
MODE under COMPUTER CONTROL.

A. Advance through the menu until CAL1

(Calibration Offset) appears.

1) If the thermocouple reading is higher
than set point temperature, press the
down arrow key and enter a negative
offset value that is equal to the number
of degrees above the 5°F tolerance.

2) If the thermocouple reading is lower
than set point temperature, press the
up arrow key and enter a positive
offset value that is equal to the number
of degrees below the 5°F tolerance.

3) Exit the setup mode.

7. Allow the oven to cycle at least two times
between adjustments.

1. Place a thermocouple in the geometric center of
the oven cavity.

2. Turn the power switch ON.

Page 39 of 75 F25105 Rev. C (1118)

A. If the temperature variance still differs more

than 5°F from the set point, verify the correct
calibration offset value was entered and
retained.

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE PROCEDURES AND ADJUSTMENTS

1) ) Adjust the calibration offset value as
outlined in step 6, until the cycling
temperature is within tolerance.

B. If the above adjustment cannot be obtained:

C. Turn the power switch OFF.

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

D. Replace the computer control and check for

proper operation.

COMPUTER CONTROL

OPERATIONAL TEST

The computer controls "Calibration Mode" is used to
manually test:

• Outputs of the control

• Keypad functionality

• Verify display and LEDs functionality

Additionally, if a problem is encountered during the
output test, a "Restore Factory Settings" option is
available.

MENU

Display Test (Al
segments of
display and the
LED's are
tested)

Exit Calibration
Mode and return
to Operation
Mode

NOTE: While in the calibration mode, on all
parameters except the Logic Output Test (LgOt), the
control outputs will be OFF.

• To change the programmed data, use the arrow
keys.

• To select the next parameter, press the Rack 1
key.

• At the end of the test, the control automatically
exits the Calibration Mode and returns to the
Operation Mode.

• After 1 minute of no key activations, the control
will return to operation mode.

1. Use this key sequence to access the calibration
mode. Up arrow; Down arrow; Rack 1; Down
arrow; Temperature; Rack 1.

ALTERNATING ON DISPLAY

PARAMETER DATA

sequence of

—

Set point temperature is displayed

or if call for heat, dashers (---)

displayed.

characters in

display window

The calibration mode contains several adjustable
parameters that must not be changed. For the "CALY"
(Calibration) Parameter, the default data option
selected must be "no".

Listed below are the parameters and data you should
find in the calibration Mode.

MENU

Calibrate (must
display no)

Logic Output
Test (see step 3)

Logic Inputs "LI"
(Factory Only)

Keyboard (see
step 4)

F25105 Rev. C (1118) Page 40 of 75

ALTERNATING ON DISPLAY

PARAMETER DATA

CALY no

LgOt*

0

*g displays as a 9

LI 21

HEY 0

2. Once in the calibration mode the display will

NOTE: If the control was calling for heat when the
calibration mode was entered, heating will resume
after exiting the test mode.

3. Press the Rack 1 key to accept the default "no"

Fig. 73

alternate between the parameter and
programmed data. The computer control outputs
are turned OFF.

A. Convection fan stops.

B. Heating stops.

under the "CALY" (calibrate) parameter and
advance the display menu to the "LgOt" (logic
output) test. In this mode, the control and logic
outputs can be turned ON for testing only.

A. Use the arrow keys to change the display to

the appropriate number for testing. Each
test starts automatically, several seconds
after number is selected.

VC4E & VC6E Series Full Size Electric Convection Ovens - SERVICE PROCEDURES AND ADJUSTMENTS

1) #0 - All control outputs are OFF (fan &
heat OFF).

#1 - Heat comes ON (2CON is
energized).

#5 - Convection fan comes ON (High
or Low speed SSR is energized).

#8 - Electronic beeper (external)
sounds.

B. If the output tests are completed

successfully, proceed to step 4.

C. If the output tests are not completed

successfully, find the source of the problem.
If the problem cannot be repaired, replace
the component and check for proper
operation.

4. Press the Rack 1 key twice to advance past the
"LI" (Logic Inputs test) and reach the "HEY"
(keyboard) test.

A. Press the desired key to display the

corresponding hexadecimal code. This
code is used internally by the control to
identify the key being pressed. See table
below.

C. Replace the computer control and check for

proper operation.

5. Press the Rack 1 key to advance the display
menu to the "dISP" (display) test. A test
sequence automatically runs on the display and
control LEDs for a visual verification that all
segments in the LED display and the internal
LEDs are functioning.

6. At the end of the test, the control exits the
calibration mode and returns to the Operation
Mode.

Restore Factory Settings

NOTE: If the computer control does not appear

to be functioning properly, do not restore factory
settings until verifying the control is configured
properly as outlined in SETUP MODE under
COMPUTER CONTROL and performing the
COMPUTER CONTROL OPERATIONAL TEST
as outlined in the above section.

1. Enter the "Calibration Mode" by using the key
sequence stated in step 1 under COMPUTER
CONTROL OPERATIONAL TEST.

A. The computer control outputs are turned

OFF.

KEY CODE KEY CODE

Up Arrow 40 Start/Stop 4

Down Arrow 80 Temp 20

½ menu 800 Rack 1 10 *

3/4 menu 4000 Rack 2 400

5/6 menu 2 Rack 3 2000

Set 200 Rack 4 1

Time 1000 Rack 5 8

Roast & Hold 8000

* Displays 10 momentarily then alternates
between Hey and 0. If pressed again, advances to
the next test.

B. If the code displayed is not correct for the

key pressed, then the keyboard is
malfunctioning.

1) Turn the power switch OFF.

Disconnect the electrical power to
the machine and follow lockout /
tagout procedures. There may be
multiple circuits. Be sure all circuits
are disconnected.

B. The display will alternate between "CALY"

and "no".

2. Press the up or down arrow key until the "rESt"
parameter displays.

3. Press the Rack 1 key and "no" displays.

4. Press the up or down arrow key to change the
display to "YES".

5. Press the Rack 1 key to select this data option
and then advance the menu to the "LgOt" (logic
output test).

NOTE: The "g" in LgOt displays as a "9".

6. Press the Rack 1 key twice to advance past the
"LI" (Logic Inputs test) and the "HEY" (keyboard)
test.

7. The "dISP" (display) test sequence automatically
runs.

8. At the end of the test, the control exits the
calibration mode and returns to the Operation
Mode.

9. Enter the "SETUP MODE" as outlined under
COMPUTER CONTROL and perform the
procedure.

Page 41 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

ELECTRICAL OPERATION

COMPONENT FUNCTION

Power Switch (S1) .... Determines the mode of operation; ON, OFF, or COOL DOWN.

Oven Light Switch

(S2) ...................

Fan Speed Switch

(S3) ...................

Alarm/Buzzer ......... Signals the end of a "Cook" cycle when cooking time expires.

Cook Timer ........... Counts the "Cook" time of the product and signals the buzzer at the end of the cycle

Door Switch .......... Allows the oven to operate when the doors are closed but stops the oven from operating

Blower Motor ......... Operates the oven cavity blower (convection fan).

Transformer (T1) ..... Provides 24VAC power to the Computer Control (VC4EC/6EC only).

Transformer (T2) ..... Provides 240VAC power to the oven control circuit and blower motor (480VAC models

Solid State
temperature

Control ...............

High Limit

Thermostat ...........

Computer Control .... Monitors temperature sensor and regulates the oven cavity temperature by controlling

Controls the oven cavity lights.

Controls blower motor speed between High and Low settings (VC4ES/6ES and VC4ED/
6ED only).

(VC4ES/6ES and VC4ED/6ED only).

when the doors are opened.

only).

Monitors temperature sensor and regulates the oven cavity temperature by controlling
2CON to energize the heating elements when the control calls for heat.

Protects the oven from temperatures above 550°F by removing power from the heating
circuit. Auto resets at 500°F.

2CON to energize the heating elements when the control calls for heat. Also, counts the
"Cook" time (normal cooking) of the product and signals the electronic alarm at the end
of the cycle. If "Roast" & "Hold" mode is selected, when the "Cook" (then hold) time
expires, the oven heating stops and the oven enters "Hold" mode. Once the oven cavity
temperature drops to 150°F, the heat comes back on and the oven cycles at this
temperature to hold the cooked product. Cook & Hold is standard on computer models.
The selected mode also determines the fixed blower speed of High for "Cook" and Low
for "Roast & Hold".

SSR1 & SSR2 ......... When SSR1 is energized by computer control, connects power to blower motor for High

fan speed operation in normal "Cook" mode. In "Roast & Hold" Mode only, SSR1 is de­energized and SSR2 is energized by computer control and connects power to blower
motor for Low fan speed operation (VC4EC/6EC only).

1CON & 2CON ........ Provides power to heating elements when both are energized. 1CON is energized when

power switch is turned ON. 2CON is energized by the temperature control when a call
for heat is made.

Power ON Light ....... Lit whenever the power switch (S1) is turned to ON or Cool Down mode.

Heat Light ............ Lit whenever temperature control is calling for heat.

Temperature Probe ... Senses the oven temperature for the solid state temperature control or the computer

control. On oven models using the solid state control, converts the temperature into a
resistance valve which is monitored by the temperature control board. The probe is an
RTD (resistance temperature detector) of the Thermistor type. As temperature increases
the resistance value decreases. On oven models using the computer control, the probe
is a "J" type thermocouple.

F25105 Rev. C (1118) Page 42 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

Mechanical
Temperature Control

KX thermostat ........

Cooling Fan .......... Circulates cooler air from outside the oven to cool components in the control area.

Fuses ................. Protect control circuit.

Regulates the oven cavity temperature by controlling 2CON to energize the heating
elements when the control calls for heat (VC4ES/6ES only).

COMPONENT LOCATION

Fig. 74

Page 43 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

STARTING AT SERIAL NUMBER 481916864

F25105 Rev. C (1118) Page 44 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4ES/6ES with Mechanical KX thermostat - Plug, Socket and Components

Page 45 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4ED/6ED with Solid State Control - Plug, Socket and Components

F25105 Rev. C (1118) Page 46 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4EC/6EC - Plug, Socket and Components (Roast & Hold Standard)

Page 47 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

SEQUENCE OF OPERATION -

VC4ES, VC6ES with Mechanical KX

Thermostat

Refer to diagram 6962 for electrical sequence of
operation.

Cook Cycle

1. Conditions.

A. Oven connected to correct voltage and is

properly grounded.

B. Power switch (S1) OFF.

C. Temperature dial set to lowest temperature

(fully CCW).

D. High limit thermostat CLOSED.

E. Oven doors closed (door switch contacts

CLOSED).

F. Oven cavity temperature below 140°F.

2. Power switch (S1) turned ON.

A. Power ON light (Amber) comes ON.

SEQUENCE OF OPERATION -

VC4ED, VC6ED with Solid State

Temperature Control

Refer to diagram 6964 for electrical sequence of
operation.

Cook Cycle

1. Conditions.

A. Oven connected to correct voltage and is

properly grounded.

B. Power switch (S1) OFF.

C. Temperature dial set to lowest temperature

(fully CCW).

D. High limit thermostat CLOSED.

E. Oven doors closed (door switch contacts

CLOSED).

F. Oven cavity temperature below 140°F.

2. Power switch (S1) turned ON.

A. Power ON light (Amber) comes ON.

B. 1CON coil energized.

C. Blower motor energized. NOTE: Motor

speed (Hi/Low) depends on position of fan
speed switch (S3).

D. Component cooling fan energized.

E. Power to oven cavity light switch (S3) wire

#1. Turns cavity lights ON/OFF and does
not affect "Cook" cycle.

3. Set thermostat to desired "Cook" temperature
and thermostat CLOSES.

A. Heating light (Clear) comes ON.

B. 2CON coil energized.

1) Heating elements powered and
heating starts.

4. Oven reaches set temperature and thermostat
OPENS.

A. Heat light goes out.

B. 2CON coil de-energized.

1) Power removed from heating elements
and heating stops.

B. 1CON coil energized.

C. Solid state temperature control energized.

1) Heating light (Clear) comes ON. 2)
2CON coil energized.

2) 2CON coil energized.

a. Heating elements powered and

heating starts.

D. Blower motor energized.

NOTE: Motor speed (Hi/Low) depends on position of
fan speed switch (S3).

E. Component cooling fan energized.

F. Power to oven cavity light switch (S3) wire

#1. Turns cavity lights ON/OFF; does not
affect "Cook" cycle.

3. Set temperature dial to desired "Cook"
temperature.

4. Oven reaches set temperature.

A. Temperature control de-energizes internal

relay and the normally open (N.O.) contacts
OPEN.

5. The oven will continue to cycle on the thermostat
until the doors are opened or the power switch
(S1) is turned to the OFF or COOL DOWN
position.

F25105 Rev. C (1118) Page 48 of 75

1) Heat light goes out.

2) 2CON coil de-energized.

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

a. Power removed from heating

elements and heating stops.

5. The oven will continue to cycle on the
temperature control until the doors are opened or
power switch (S1) is turned to the OFF or COOL
DOWN position.

Timer Cycle, Cooking

(KX Thermostat or Solid State Control)

NOTE: The "Cook" 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 power switch turned ON, power is
supplied to "Cook" timer terminal 1.

2. Set "Cook" timer to desired time.

A. Contacts 1 & 3 close, timer motor is

energized and timing "down" begins

3. Time expires on "Cook" timer .

A. Contacts 1 & 3 open, timer motor is

deenergized and timing stops.

B. Contacts 1 & 4 close.

1) Buzzer energized and sounds.

NOTE: The buzzer continues to sound until the timer
dial is set to the OFF position or additional time is set.

Cool Down Cycle

(KX Thermostat or Solid State Control)

1. Conditions.

A. Oven is ON.

B. Oven cavity temperature needs to be

lowered.

C. Doors are open (door switch contacts

OPEN).

D. Fan speed switch (S3) set to "Hi".

2. Power Switch (S1) turned to COOL DOWN.

A. Power ON light (Amber) goes out.

B. Convection fan motor energized.

NOTE: Fan speed switch (S3) can be set to operate
at high or low fan speed.

3. If doors are CLOSED (door switch contacts
CLOSED):

A. Power ON light (Amber) comes ON.

B. 1CON coil is energized but heating

elements are not powered.

D. Power is supplied to:

1) "Cook" timer terminal 1. If a time is
dialed, timer will operate and buzzer
will sound when timer reaches zero.

2) Oven cavity light switch (S3) wire #1.
Turns cavity lights ON/OFF; does not
affect "Cool down" cycle.

4. The oven will remain in this condition until the
power switch (S1) is turned to the OFF or ON
position.

SEQUENCE OF OPERATION -

VC4EC, VC6EC (Computer Control)

Refer to diagram 6966 for electrical sequence of
operation.

Cook Cycle

1. Conditions.

A. Oven connected to correct voltage and is

properly grounded.

B. Power switch (S1) OFF.

C. Computer control is setup properly and

ready to use. NOTE: The set point
temperature of the computer control will be
the last temperature that was set.

D. High limit thermostat CLOSED.

E. Oven doors closed (door switch contacts

CLOSED).

F. Oven cavity temperature below 140°F.

2. Power switch (S1) turned ON.

A. 1CON coil energized.

B. 24VAC transformer (T1) is energized.

1) Computer control is energized and
performs a power ON self test before
energizing outputs. If the control
passes self test, then the outputs are
energized and operation sequence
continues. If control does not pass self
test then the corresponding error code
is displayed.

C. Component cooling fan energized.

D. Power is connected to:

1) Terminal 1 on solid state relay 1 (SSR1

- load side) and solid state relay 2
(SSR2 - load side).

C. Component cooling fan energized.

Page 49 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

2) Pin 3 (C3-3) on computer control (input
"IN-2").

3) Oven cavity light switch (S2). Turns
cavity lights ON/OFF; does not affect
"Cook" cycle.

3. Computer control senses oven cavity
temperature through probe input. With the oven
cavity temperature below set point, the output
from pin C3-2 is activated.

A. Oven "Heat Light" on the control comes ON.

B. 2CON coil energized.

1) Heating elements powered and
heating starts.

C. The controls 5VDC output from pins C2-2 (-)

and C2-8 (+) is activated and SSR1 relay is
energized.

1) Convection fan motor is energized
(High speed).

4. Oven reaches set point temperature.

A. Computer control de-activates the output

from pin C3-2.

1. Oven "Roast & Hold" light on the control comes
ON.

2. Convection fan will operate at Low speed,
throughout the "Roast & Hold" cycle.

A. The computer control 5VDC output from

pins C2-2 (-) and C2-8 (+) is de-activated
and SSR1 relay is de-energized.

1) Power is removed from convection fan
motor high speed terminal.

B. The computer control 5VDC output from

pins C2-1 (-) and C2-8 (+) is activated and
SSR2 relay is energized.

1) Power is applied to the convection fan
motor low speed terminal.

3. Beeper sounds momentarily to indicate the end
of first stage cooking (oven operates normally at
the temperature and time selected until time
expires).

4. The display flashes HOLD as the oven enters
HOLD mode. This is also considered second
stage cooking (oven heating stops but product
continues to cook on residual heat).

1) 2CON coil de-energized.

a. Power removed from heating

elements and heating stops.

B. Oven "Heat Light" on the control goes out.

C. Oven "Ready Light" on the control comes

ON.

D. Electronic beeper sounds momentarily.

5. The oven will continue to cycle on the computer
control until the doors are opened or power
switch (S1) is turned to the OFF or COOL DOWN
position.

Temperature and Time Cycle (Cooking)

NOTE: The computers internal "Cook" timer operates

independently of the heating cycle. Additional time
can be set or the timer can be stopped and re-started
throughout the cooking cycle. Refer to the Instructions
Manual for specific operating instructions of the oven
Computer Control.

Roast and Hold Cycle

NOTE: For a detailed explanation of the "Roast &

Hold" mode, refer to the Instructions Manual F31159
as outlined under SETTING THE OVEN FOR ROAST
& HOLD and ROAST & HOLD OPERATION. In "Roast
& Hold" mode, the operation of the computer control
is identical to the normal Cook Cycle with these
exceptions:

A. Convection fan motor is de-energized.

5. After the oven temperature drops below 150°F,
the heat comes back ON and cycles as needed,
to maintain the "Hold" temperature of 150°F.

A. Convection fan motor energized (Low

speed).

6. The oven continues to cycle in this manner until
one of the following occurs:

A. The "Roast & Hold" mode is turned OFF.

B. Power switch (S1) is turned to the OFF or

COOL DOWN position.

Cool Down Cycle

1. Conditions.

A. Oven is ON.

B. Oven cavity temperature needs to be

lowered.

C. Doors are open (door switch contacts

OPEN).

D. Power switch (S1) set to either ON or OFF.

2. Power Switch (S1) turned to COOL DOWN.

A. Power is connected through power switch

(S1) to the convection fan motor high speed
terminal.

F25105 Rev. C (1118) Page 50 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

1) Convection fan motor energized (High
speed).

3. The oven will continue to operate in COOL
DOWN mode until the power switch (S1) is
turned to the OFF or ON position.

SCHEMATICS AND WIRING DIAGRAMS

VC4ES, VC6ES with Mechanical (KX) Controls, 208-240V Schematics

VC4ES, VC6ES with Mechanical (KX) Controls, 208-240V Wiring Diagram

VC4ES, VC6ES with Mechanical (KX) Controls, 480V Schematic

VC4ES, VC6ES with Mechanical (KX) Controls, 480V Wiring Diagram

VC4ED, VC6ED with Solid State Temperature Control, 208-240V Schematic

VC4ED, VC6ED with Solid State Temperature Contol, 208-240V Schematic - Starting at Serial Number 481916864

VC4ED, VC6ED with Solid State Temperature Control, 208-240V Wiring Diagram

VC4ED, VC6ED, with Solid State Tempature Control, 208-240V Wiring Diagram - Starting at Serial Number
481916864

VC4ED, VC6ED with Solid State Temperature Control, 480V Schematic

VC4ED, VC6ED with Solid State Temperature Control, 480V Wiring Diagram

VC4EC, VC6EC Computer Control, 208-240V (Roast & Hold Standard) Schematic

VC4EC, VC6EC Computer Control, 208-240V (Roast & Hold Standard) Wiring Diagram

VC4EC, VC6EC Computer Control, 480V (Roast & Hold Standard) Schematic

VC4EC, VC6EC Computer Control, 480V (Roast & Hold Standard) Wiring Diagram

Page 51 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4ES, VC6ES with Mechanical (KX) Controls, 208-240V

F25105 Rev. C (1118) Page 52 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4ES, VC6ES with Mechanical (KX) Control, 208-240V

Page 53 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

Fig. 81

F25105 Rev. C (1118) Page 54 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4ES, VC6ES with Mechanical (KX) Controls, 480V

Page 55 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4ES, VC6ES with Mechanical (KX) Control, 480V

F25105 Rev. C (1118) Page 56 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

Fig. 84

Page 57 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4ED, VC6ED with Solid State Temperature Control, 208-240V Schematic

F25105 Rev. C (1118) Page 58 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4ED, VC6ED with Solid State Temperature Control, 208-240V - STARTING AT SERIAL NUMBER 481916864

Page 59 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4ED, VC6ED with Solid State Temperature Control, 208-240V

F25105 Rev. C (1118) Page 60 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4ED, VC6ED with Solid State Temperature Control, 208-240V - STARTING AT SERIAL NUMBER 481916864

Page 61 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

Fig. 89

F25105 Rev. C (1118) Page 62 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4ED, VC6ED with Solid State Temperature Control, 480V

Page 63 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4ED, VC6ED with Solid State Temperature Control, 480V

F25105 Rev. C (1118) Page 64 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

Fig. 92

Page 65 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4EC, VC6EC Computer Control, 208-240V (Roast & Hold Standard)

F25105 Rev. C (1118) Page 66 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4EC, VC6EC Computer Control, 208-240V (Roast & Hold Standard)

Page 67 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

Fig. 95

F25105 Rev. C (1118) Page 68 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4EC, VC6EC Computer Control, 480V (Roast & Hold Standard)

Page 69 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

VC4EC, VC6EC Computer Control, 480V (Roast & Hold Standard)

F25105 Rev. C (1118) Page 70 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - ELECTRICAL OPERATION

Fig. 98

Page 71 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - TROUBLESHOOTING

TROUBLESHOOTING

Certain procedures in this section require electrical test or measurements while power is applied to the
machine. Exercise extreme caution at all times. If test points are not easily accessible, disconnect power
and follow lockout / tagout procedures, attach test equipment and reapply power to the test.

ALL MODELS

SYMPTOMS POSSIBLE CAUSES

1. Line voltage incorrect.

2. Power switch (S1) malfunction.
Blower motor doesn’t run with power switch in "ON"
"COOL DOWN" or position.

Blower motor doesn’t run with power switch "ON", but
oven heats.

Blower motor doesn’t run in "Cool Down", but runs ok in
"ON" position.

3. Fan speed switch (S3) malfunction.

4. Interconnecting wiring malfunction.

5. Motor inoperative.

1. Door switch malfunction.

2. Interconnecting wiring malfunction.

3. Motor inoperative.

1. Power switch (S1) malfunction.

2. Fan speed switch (S3) malfunction.

3. Interconnecting wiring malfunction.

1. Line voltage incorrect.

Excessive or low heat in oven.

Mechanical Timer inoperative or not functioning properly.

Component cooling Fan does not run.

Uneven Cooking.

2. Heating element malfunction.

3. Contactor malfunction.

4. Convection Fan motor malfunction.

5. Temperature probe malfunction or mechanical

thermostat malfunction.

6. Temperature control not calibrated.

7. Temperature control malfunction.

1. Interconnecting wiring malfunction.

2. Line voltage incorrect.

3. Timer malfunction.

1. Motor inoperable.

2. Interconnecting wiring malfunction.

1. Convection Fan motor speed/direction.

2. Air flow Baffles missing or damaged.

3. Line voltage incorrect.

4. Heating element(s) malfunction.

5. Contactor malfunction.

F25105 Rev. C (1118) Page 72 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - TROUBLESHOOTING

SYMPTOMS POSSIBLE CAUSES

1. High ambient temperatures.

Intermittent operation problems.

No power to oven controls.

No heat, convection fan motor runs.

No power to temperature control.

Door does not seal or shut properly

2. Wiring connections loose.

3. Cooling fan malfunction.

1. Main circuit breaker OPEN.

2. Control circuit fuses OPEN.

3. Power switch (S1) inoperative.

4. Transformer (T2) inoperative (480V only).

1. High limit thermostat OPEN.

2. Heating element malfunction.

3. Contactor malfunction.

4. Temperature control malfunction.

1. Power switch (S1) in "Cool Down".

2. Door or door switch open.

1. Doors out of adjustment.

2. Door chain out of adjustment or broken

(simultaneous doors).

3. Door catch roller out of adjustment or broken

(independent doors).

4. Door seals damaged.

COMPUTER CONTROL MODELS ONLY

SYMPTOM POSSIBLE CAUSES

1. High limit switch open.

Oven does not heat.

High limit thermostat shutting OFF heat.

Oven not hot enough.

2. Temperature probe malfunction.

3. Computer control malfunction.

1. Temperature probe malfunction.

2. Computer control malfunction.

1. Temperature probe malfunction.

2. Computer control range high (rH1) setting to low.

See SETUP MODE under COMPUTER CONTROL.

3. Computer control malfunction.

Page 73 of 75 F25105 Rev. C (1118)

VC4E & VC6E Series Full Size Electric Convection Ovens - TROUBLESHOOTING

SYMPTOM POSSIBLE CAUSES

1. Line voltage incorrect.

2. Power switch (S1) malfunction.

3. Fan speed switch (S3) malfunction.

4. Solid sate relay (SSR) malfunction. See SOLID
Blower motor doesn’t run with power switch in "ON" or
"COOL DOWN" position.

STATE RELAY TEST under COMPUTER
CONTROL.

5. Interconnecting wiring malfunction.

6. Motor inoperative.

7. Computer control malfunction. See COMPUTER

CONTROL OPERATIONAL TEST.

Error Codes

In the display window, the error code will
alternate between the code and the oven cavity
temperature or dashes if the oven is calling for
heat (heat light on). The exact error code
displayed will depend on the priority assigned to
the problem in the EPROM'S software. The lower
the error code number, the higher the priority. If

NOTE: To check a "Setup Parameter" and its
corresponding "Data Value", see SETUP MODE
under COMPUTER CONTROL.

NOTE: If the cause of the error is not apparent, check
for these conditions as they may also cause errors to
occur: Electrical noise or a noise event, excess
environmental moisture or temperature, or vibration.

more than one problem occurs at the same time,
the error code assigned to the higher priority
problem will be displayed. Refer to the error code
table below to solve the problem. If the lower
priority problem still exists, the next error code
will be displayed. When the condition causing the
error is resolved, normal oven operation can
resume.

CODE & PROBLEM PROBABLE CAUSE SOLUTION

Er01 - ROM checksum error Internal ROM malfunction Cycle power

Er02 - RAM checksum error Internal RAM malfunction Cycle power

Er03 - Ambient sensor error Ambient temperature is below 32°F

Check ambient temperature at the
control.

Er04 - Configuration error Microprocessor malfunction Cycle power

Er05 - EPROM error

1

Power loss while storing data Cycle power

• Check the InP1 setup
parameter. Verify it matches

Er06 - Zone 1 A/D underflow error

• Incorrect sensor type

• Measuring temperature outside
the sensor range

your sensor.

• Check sensor and connections
for a reversed or open sensor. If
the condition causing the error is
resolved, the error will clear.

F25105 Rev. C (1118) Page 74 of 75

VC4E & VC6E Series Full Size Electric Convection Ovens - TROUBLESHOOTING

CODE & PROBLEM PROBABLE CAUSE SOLUTION

• Check the InP1 setup
parameter. Verify it matches
your sensor.

Er07 - Zone 1 A/D overflow error Open sensor

• Check sensor and connections
for a reversed or open sensor. If
the condition causing the error is
resolved, the error will clear.

• Cycle power

Er10 - Stack overflow error Microprocessor malfunction

• Check sensor and connections
for a reversed or open sensor

• Check the InP1 setup
parameter. Verify it matches

Er11 - Open sensor error Open sensor

your sensor.

• Check sensor and connections
for a reversed or open sensor

• Check the InP1 setup

Er12 - Shorted sensor

• Incorrect sensor type

• Measuring temperature outside
the sensor range

parameter. Verify it matches
your sensor.

• Check sensor and connections
for a reversed or open sensor

1

Should only see when a new EPROM is installed and powered for the first time.

Page 75 of 75 F25105 Rev. C (1118)