Vulcan Hart ECO2D Service Manual

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SERVICE MANUAL
HALF-SIZE CONVECTION OVENS ELECTRIC AND GAS
MODEL ML
ELECTRIC
GCO2D Shown
This Manual is prepared for the use of trained Vulcan Service Technicians and should not be used by those not properly qualified. If you have attended a Vulcan Service School for this product, you may be qualified to perform all the procedures described in this manual.
ECO2D 114570
ECO2C 114572
GAS
GCO2D 114569
GCO2C 114571
- NOTICE -
Reproduction or other use of this Manual, without the express written consent of Vulcan-Hart, is prohibited.
A product of VULCAN-HART LOUISVILLE, KY 40201-0696 Form 24575 (12/96)
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HALF-SIZE CONVECTION OVENS
TABLE OF CONTENTS
GENERAL............................................................................. 3
Introduction ....................................................................... 3
Specifications ..................................................................... 3
Gas Ovens................................................................ 3
Electric Ovens ............................................................. 3
Tools ............................................................................ 3
REMOVAL AND REPLACEMENT OF PARTS ................................................. 4
Covers and Panels ................................................................. 4
Control Panel Components ........................................................... 5
Blower And/or Blower Motor........................................................... 6
Oven Door........................................................................ 7
Door Switch ....................................................................... 8
Heat Exchanger (Gas Ovens) ......................................................... 8
Burner (Gas Ovens)................................................................. 9
Gas Valve (Gas Ovens).............................................................. 9
Heating Elements (Electric Ovens) .................................................... 10
SERVICE PROCEDURES AND ADJUSTMENTS .............................................. 11
Temperature Probe Test (All Models) .................................................. 11
Verification of Spark at Spark Probe ................................................... 11
Gas Pressure Adjustment ........................................................... 12
Spark Ignition Control Test .......................................................... 12
Electronic Control ................................................................. 13
Solid State Control Test ............................................................. 14
Solid State Control Calibration ........................................................ 14
Door Switch Adjustment............................................................. 15
Door Reversal .................................................................... 16
Door Adjustment .................................................................. 17
Blower Adjustment................................................................. 17
Element Test ..................................................................... 17
ELECTRICAL OPERATION .............................................................. 18
Component Function ............................................................... 18
Component Location ............................................................... 19
Sequence of Operation ............................................................. 20
Ignition Module ............................................................ 20
Gas Oven................................................................ 20
Electric Oven ............................................................. 23
Schematics Gas Ovens ............................................................. 26
GCO2D ................................................................. 26
GCO2C ................................................................. 27
Wiring Diagram - Gas Ovens......................................................... 28
GCO2D ................................................................. 28
GCO2C ................................................................. 30
Schematic-Electric Ovens ........................................................... 32
ECO2D ................................................................. 32
ECO2C ................................................................. 33
Wiring Diagram Electric Ovens ....................................................... 34
ECO2D ................................................................. 34
ECO2C ................................................................. 36
TROUBLESHOOTING .................................................................. 38
Electric Ovens .................................................................... 38
Gas Ovens ...................................................................... 39
© VULCAN 1996
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HALF-SIZE CONVECTION OVENS - GENERAL
GENERAL
INTRODUCTION
General
This manual will cover half-size electric and gas convection ovens that use either a solid state control or an electronic control.
Procedures in this manual are applicable to both gas and electric ovens unless specified.
SPECIFICATIONS
GAS OVENS
GAS DATA ELECTRICAL DATA
INPUT BTU/HR MANIFOLD PRESSURE LOAD
Natural Propane Natural Propane 120V
Single Oven 2500 2500 3.5" W.C. 10"W.C. 950 8
Stacked Oven 5000 5000 3.5" W.C 10"W.C. 1900 16
ELECTRIC OVENS
NOMINAL AMPS PER LINE WIRE
3-PHASE LOADING
TOTAL
KW
Single Oven 5.5 2.5 0 3.0 22.9 10.4 12.5 19.9 9.0 10.9 26.5 23.0
Stacked Ovens
11.0 5.0 0 6.0 45.8 20.8 25.0 39.7 18.0 21.7 52.9 45.9
(KW PER PHASE)
208V 240V 208V 240V
L1-L2 L2-L3 L1-L3 L1 L2 L3 L1 L2 L3
3 PHASE 1 PHASE
(Watts)
AMP/LINE
TOOLS
Standard set of hand tools
VOM with AC current tester (Any VOM with a sensitivity of at least 20,000 ohms per volt can be used.)
Temperature tester
Manometer (Gas Ovens)
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HALF-SIZE CONVECTION OVENS - REMOVAL AND REPLACEMENT OF PARTS
REMOVAL AND REPLACEMENT OF PARTS
COVERS AND PANELS
WARNING:
POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.
WARNING:
SERVICING THE UNIT. (When applicable)
Top Front Cover
1. The top front cover is secured with four screws, two on each side of cover. Remove these screws then pull cover off unit.
2. Reverse the procedure to install.
DISCONNECT THE ELECTRICAL
SHUT OFF THE GAS BEFORE
Right Side Panel
1. Remove the three screws which secure the right side of the control panel.
2. Loosen the two screws on the right side of the top front cover.
3. Remove the remaining eight screws securing the right side panel.
4. Pull the right side panel out at the bottom then down to remove.
5. Reverse the procedure to install.
Control Panel
1. On gas models, remove the handle from the manual gas valve.
2. Remove the three screws from the left front and loosen the three screws on the right side of the control panel.
3. Pull the panel away from the oven.
4. Unplug the lead wires to the control panel components and disconnect the temperature probe leads.
5. Reverse the procedure to install.
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HALF-SIZE CONVECTION OVENS - REMOVAL AND REPLACEMENT OF PARTS
CONTROL PANEL
COMPONENTS
Removable Components
Listed on the illustration.
Procedure
WARNING
1. Remove the control panel as outlined under
: UNPLUG UNIT BEFORE SERVICING.
"COVERS AND PANELS".
2. Disconnect the wire leads at the component to be replaced.
3. Remove the component.
4. Reverse the procedure to install the new component, then check oven for proper operation.
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HALF-SIZE CONVECTION OVENS - REMOVAL AND REPLACEMENT OF PARTS
BLOWER AND/OR BLOWER
MOTOR
WARNING
1. Remove racks and the right rack support.
2. Remove baffle panel by lifting up and out.
3. For gas ovens only, remove the heat exchanger
: UNPLUG UNIT BEFORE SERVICING.
as outlined under “HEAT EXCHANGER”.
8. Disconnect the wire leads to the motor.
A. P1 (purple) to wire# 11 B. Orange (Low speed) to wire# 12 C. Blue (high speed) to wire# 13 D. Red wires connected together.
9. Remove the bolts that secure the motor to the motor mounting plate and remove the motor from the oven.
4. Loosen set screws on blower hub.
5. Remove blower from motor shaft. You may have to use a bearing puller.
6. If the blower only is to be replaced, reverse procedure to install and check blower to be parallel with the motor mounting plate as outlined under "BLOWER ADJUSTMENT" in "SERVICE PROCEDURES AND ADJUSTMENTS”. If the motor is to be replaced, continue to step 7.
10. Place new motor in position on the motor mounting plate and route the wiring through the grommet in the component panel.
11. Install mounting pads and bolts. DO NOT tighten mounting bolts.
12. Slide the blower onto motor shaft until hub is flush with end of shaft and tighten set screws.
13. Adjust motor position until blower is parallel to oven cavity wall with a spacing of ¼" as outlined under "BLOWER ADJUSTMENT" in "SERVICE PROCEDURES AND ADJUSTMENTS".
14. Install baffle panel, rack guides and racks.
7. Remove the right side panel.
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HALF-SIZE CONVECTION OVENS - REMOVAL AND REPLACEMENT OF PARTS
OVEN DOOR
Removal
WARNING:
1. Remove the top front cover as outlined under "COVERS AND PANELS".
2. Remove the door switch lever from the door shaft.
3. Remove the door switch bracket.
4. While supporting the door, remove the bearing, door plate and spacer.
UNPLUG UNIT BEFORE SERVICING.
Disassembly
1. Open the door.
2. Remove the door handle and latch plate.
3. Remove the screws which secure the inner and outer door panels to the door frame.
4. Remove the inner and outer door panel.
5. Remove the four screws and lift the window assembly out.
5. Lift the door from the lower bearing.
6. 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".
NOTE:
the window and the door panel.
6. Reverse the procedure to install the new window and adjust the door as outlined under “DOOR ADJUSTMENT”.
Use high temperature silicone between
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WARNING:
HALF-SIZE CONVECTION OVENS - REMOVAL AND REPLACEMENT OF PARTS
DOOR SWITCH
HEAT EXCHANGER (GAS
UNPLUG UNIT BEFORE SERVICING.
OVENS)
1. Remove the top front cover as outlined under "COVERS AND PANELS".
2. Disconnect the leads to the door switch.
3. Remove the switch which is secured by two screws.
4. Reverse the procedure to install the new switch.
5. Adjust the door switch as outlined under "DOOR SWITCH ADJUSTMENT" in "SERVICE PROCEDURES AND ADJUSTMENTS".
WARNING:
WARNING:
SERVICING THE UNIT.
1. Remove racks and the right rack support.
2. Remove baffle panel by lifting up and out.
3. Remove the screws that secure the heat exchanger and remove it from the oven.
UNPLUG UNIT BEFORE SERVICING.
SHUT OFF THE GAS BEFORE
4. Reverse procedure to install.
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HALF-SIZE CONVECTION OVENS - REMOVAL AND REPLACEMENT OF PARTS
BURNER (GAS OVENS)
WARNING:
WARNING:
SERVICING THE UNIT.
1. Remove racks and the right rack support.
2. Remove baffle panel by lifting up and out.
3. Remove the right side panel as outlined under “COVERS AND PANELS”.
4. Disconnect the lead wires to the electrode assembly.
5. Remove the heat exchanger as outlined under “HEAT EXCHANGER”.
6. Remove the screws from the burner bracket and pull the burner into the oven cavity.
7. Remove the screws that secure the electrodes to the burner bracket.
UNPLUG UNIT BEFORE SERVICING.
SHUT OFF THE GAS BEFORE
GAS VALVE (GAS OVENS)
WARNING:
WARNING:
SERVICING THE UNIT.
WARNING:
DURING SERVICING MUST BE CHECKED FOR LEAKS. CHECK WITH A SOAP AND WATER SOLUTION (BUBBLES). DO NOT USE AN OPEN FLAME.
A. CHECK ALL JOINTS PRIOR TO THE
B. CHECK ALL JOINTS BEYOND GAS
1. Remove the right side panel and control panel as outlined under “COVERS AND PANELS”.
2. Disconnect the lead wires at the gas valve.
3. Disconnect the gas line fitting going to the burner at the top of the gas valve.
UNPLUG UNIT BEFORE SERVICING.
SHUT OFF THE GAS BEFORE
ALL GAS JOINTS DISTURBED
GAS VALVE BEFORE LIGHTING UNIT.
VALVE AFTER UNIT IS LIT.
8. Reverse procedure to install.
NOTE:
positioned toward the front of the oven.
When installed, the electrodes are
4. Remove the gas valve from the nipple between the it and the manual gas valve.
5. Reverse procedure to install.
6. Adjust the gas valve as outlined under “GAS PRESSURE ADJUSTMENT”.
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HALF-SIZE CONVECTION OVENS - REMOVAL AND REPLACEMENT OF PARTS
HEATING ELEMENTS
(ELECTRIC OVENS)
WARNING:
POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.
1. Remove racks and the right rack support.
2. Remove baffle panel by lifting up and out.
3. Remove the right side panel as outlined under “COVERS AND PANELS”.
4. Disconnect the lead wires to the heating elements.
5. Remove the screws from the clamps that secure the heating element assembly.
DISCONNECT THE ELECTRICAL
TEMPERATURE PROBE
Procedure
WARNING
1. Remove the control panel as outlined under
2. Disconnect the probe leads at the temperature
3. Remove probe from the probe guard and push
NOTE:
the probe should be inserted into the probe guard.
: UNPLUG UNIT BEFORE SERVICING.
"COVERS AND PANELS".
control.
it thru the oven wall into the control panel area.
When installing, only the metal surface of
6. Pull the top of the heating element assembly into the oven cavity until the ends of the elements are inside the oven cavity. Lift up and remove the lower clamp from between the side wall and the bottom of the oven cav ity.
NOTE:
angle. The hole in the inside oven cavity wall may not line up straight with the oven cavity outer shell.
4. Reverse the procedure to install the new probe.
5. Adjust the temperature control as outlined
The probe may hav e to be inserted at an
under "TEMPERATURE CONTROL CALIBRATION" in "SERVICE PROCEDURES AND ADJUSTMENTS".
7. Remove the clamps from the heating element assembly and replace the element(s).
8. Reverse procedure to install.
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HALF-SIZE GAS CONVECTION OVENS - SERVICE PROCEDURES AND ADJUSTMENTS
SERVICE PROCEDURES AND ADJUSTMENTS
WARNING:
MEASUREMENTS WHILE POWER IS APPLIED TO THE MACHINE. EXERCISE EXTREME CAUTION AT ALL TIMES. IF TEST POINTS ARE NOT EASILY ACCESSIBLE, DISCONNECT POWER, ATTACH TEST EQUIPMENT AND REAPPLY POWER TO TEST.
WARNING:
1. Remove the right side panel as outlined under "COVERS AND PANELS".
2. Remove the probe lead wires from the electronic control.
3. Test the probe with an ohmmeter.
TEMPERA-
TURE
CERTAIN PROCEDURES IN THIS SECTION REQUIRE ELECTRICAL TEST OR
TEMPERATURE PROBE
TEST (ALL MODELS)
UNPLUG UNIT BEFORE SERVICING.
RESISTANCE
in ±10%
in (F
77 90000
240 4077
260 3016
VERIFICATION OF SPARK
AT SPARK PROBE
WARNING:
WARNING:
SERVICING THE UNIT.
1. Remove the right side panel and control panel as outlined under “COVERS AND PANELS”.
2. Disconnect the high voltage lead from the electrode.
WARNING:
YOUR HANDS FOR THIS TEST. THE MANUAL GAS VALVE MUST BE CLOSED.
3. Clamp the wire in such a manner that the end of the wire is 3/16" from the frame of the oven.
NOTE:
from the oven or sparking may not occur even though the probe circuits are functioning properly.
UNPLUG UNIT BEFORE SERVICING.
SHUT OFF THE GAS BEFORE
DO NOT HOLD THE WIRE WITH
It is critical that the wire be held 3/16" away
280 2266
300 1726
320 1332
340 1041
360 822
380 656
400 529
425 424
450 334
475 266
WARNING:
POWER TO BE APPLIED TO THE UNIT DURING THE TEST. USE EXTREME CAUTION AT ALL TIMES.
4. Plug the unit in and set the temperature controller to the maximum setting.
5. Turn the power switch on.
6. Sparking should occur after a 15 second purge time. Arcing from the lead wire to the oven frame should be observed at this time.
THE FOLLOWING STEPS REQUIRE
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HALF-SIZE GAS CONVECTION OVENS - SERVICE PROCEDURES AND ADJUSTMENTS
GAS PRESSURE
ADJUSTMENT
WARNING:
WARNING:
SERVICING THE UNIT.
1. Remove the right side panel and control panel as outlined under “COVERS AND PANELS”.
2. Remove the plug from the test port and install the manometer.
WARNING:
POWER TO BE APPLIED TO THE UNIT DURING THE TEST. USE EXTREME CAUTION AT ALL TIMES.
3. Plug in the unit and turn on the gas.
4. Set the temperature control to the highest setting and turn the power switch on. The burner must be lit while adjusting the pressure.
5. Turn the adjustment screw to obtain the proper gas pressure.
UNPLUG UNIT BEFORE SERVICING.
SHUT OFF THE GAS BEFORE
THE FOLLOWING STEPS REQUIRE
GAS TYPE SETTING AT OUTPUT
OF GAS VALVE
Natural 3.5 inches W.C.
Propane 10 inches W.C.
NOTE:
10.5 (Propane) inches W.C., the desired output cannot be obtained and the oven will overate at a lower BTU.
If input pressure is below 4.0 (Natural) or
SPARK IGNITION CONTROL
TEST
WARNING:
NOTE:
to the oven ground.
No Gas Ignition & No Sparking
1. Remove the right side panel as outlined under “COVERS AND PANELS”.
2. Plug in the unit and set the temperature controller to 350°.
3. Turn the power switch on.
UNPLUG UNIT BEFORE SERVICING.
Verify that the ground terminal is connected
Turn screw clockwise
Turn screw counterclockwise pressure.
to increase pressure.
to decrease
4. Check for 24 VAC between the power terminal and ground terminal.
A. If 24 VAC is present, replace the spark
ignition control.
B. If 24 VAC is not present, check the
transformer, temperature controller, and switches.
No gas ignition - sparking occurs
1. Remove the right side panel as outlined under “COVERS AND PANELS”.
2. Plug in the unit and set the temperature controller to 350°.
3. Turn the power switch on.
4. Check for 24 VAC between the gas valve terminal and the ground terminal. The voltage should be present after and during the 10 second ignition period.
A. If 24 VAC is present, check the gas valve
and gas supply.
B. If 24 VAC is not present, replace the spark
ignition control.
the 15 second purge
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HALF-SIZE GAS CONVECTION OVENS - SERVICE PROCEDURES AND ADJUSTMENTS
ELECTRONIC CONTROL
SPECIAL KEY FUNCTIONS
functions press the specified keys while turning the oven on. You can not toggle between functions. Each function has to be entered from the off position.
NOTE:
See diagram following the table.
CALIBRATE OVEN
1. Place a thermocouple near the geometric
2. Cycle oven until the cavity temperature stabiliz-
3. Turn the oven off.
4. Enter the calibration mode.
There are four hidden keys on the control.
HOLD KEYS 1 & 3 4 & 9 6 & 8
FUNCTION Calibration Mode Change between (C & (F Display test
- Perform Calibration at 350(F
center of the oven cavity.
es. (usually 3 cycles)
- To activate these
5. Compare the set temperature to the measured temperature.
6. Adjust the temperature on the display to match the measured temperature.
7. Press key 3 to store the calibration information.
DISPLAY TEST
continuous test until the oven is turned off. Each segment of the displays will be lit in sequence, each LED in order and then each digit will light.
ERROR CODES
- The control will cycle through a
CODES CONDITIONS
E-01 High Limit Error - Check open probe.
E-02 Low Limit Error - check for 6 VAC from transformer.
Check control pins 1-2 for 12 VAC & pins 2-3.
E-03 Control compartment ambient temperature is above 215(F
E-04 Control compartment ambient temperature is below 32(F
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HALF-SIZE GAS CONVECTION OVENS - SERVICE PROCEDURES AND ADJUSTMENTS
SOLID STATE CONTROL
TEST
NOTE:
1. Remove the screws from the control panel and
2. Place a thermocouple in the geometric center
3. Set the temperature to the maximum setting.
4. Turn the power switch to ON.
Oven temperature must be below 450(F.
pull the control panel away from the oven to access the control wiring.
of the oven cavity.
SOLID STATE CONTROL
CALIBRATION
1. Place a thermocouple in the geometric center of the oven cavity.
2. Set the On-Off-Cool Down switch to ON.
3. Set the temperature control to 350 degrees F.
4. Allow the oven to cycle until the oven temperature stabilizes. (cycle at least three times)
5. Record the temperature at which the HEAT LIGHT goes off and on.
A. Check for at least two complete heating
cycles.
6. Calculate the differential by subtracting the temperature indicated when the heat light comes on from the temperature indicated when the heat light goes out.
5. Check for supply voltage across: 200-240 volts - pin 10 to pin 6 120 volts - pin 9 to pin 6
A. If correct, proceed to step 7. B. If incorrect, go to step 6.
6. Check for supply voltage across: 200-240 volts - pin 7 to pin 10 and pin 8 to pin 10 120 volt - pin 7 to pin 9 and pin 8 to pin 9
A. If correct, proceed to step 7. B. If incorrect, problem is not with the
temperature control. Return to Trouble­shooting Guide.
7. Turn the temperature control to the minimum setting.
NOTE:
8. Check for zero (O) Volts across:
Oven temperature must be above 300(F.
200-240 volts - pin 6 to pin 10 120 volt - pin 6 to pin 9 A. If correct the problem is not with the
temperature control. Return to Trouble­shooting Guide.
Differential = Heat light OFF - Heat light ON.
Example: 360 (light out) - 340 (light on) = 20( F differential.
A. The differential calculated should be
less than 20 degrees F.
(1) If the differential is more than 20
degrees F, check temperature probe and temperature control board as outlined under "TEMPERATURE PROBE TEST" and "SOLID STATE CONTROL TEST".
7. Calculate the average temperature by adding the temperature indicated when the heat light goes out to the temperature indicated when the heat light comes on and dividing this answer by
2.
[Temp.(light off)+ Temp.(light on)] ÷ 2 = Average Temperature
Example: (360 + 340) ÷ 2 = 700 ÷ 2 = 350( F average temperature
B. If incorrect, replace the temperature
control.
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HALF-SIZE GAS CONVECTION OVENS - SERVICE PROCEDURES AND ADJUSTMENTS
8. If the average temperature differs more than 10 degrees F from the dial settings:
A. Pencil mark the knob pointer position as a
reference point on the control panel next to the dial plate.
B. Remove the temperature control knob.
C. Loosen the two dial plate mounting screws
and the temperature control mounting nut. Loosen only enough to turn the dial plate.
DOOR SWITCH
ADJUSTMENT
WARNING:
POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.
1. Remove the upper front cover as outlined under "COVERS AND PANELS".
2. The door switch actuator should be operated by the switch lever when the door is about ½" from being closed.
3. If adjustment is necessary, use the following procedures.
A. Loosen the two switch mounting screws.
B. Adjust the switch bracket to obtain the
DISCONNECT THE ELECTRICAL
correct setting as outlined in step 2.
D. Rotate the dial plate until the temperature
calculated in step 7 is in line with the pencil mark.
E. If the above adjustment cannot be
obtained, check temperature probe and temperature control board as outlined under "TESTING TEMPERATURE CONTROL BOARD".
C. Tighten the two switch bracket mounting
screws.
D. If the adjustment can not be obtained by
moving the switch, you can bend the tab of the actuator lever.
4. Install the upper front cover.
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HALF-SIZE GAS CONVECTION OVENS - SERVICE PROCEDURES AND ADJUSTMENTS
DOOR REVERSAL
WARNING:
POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.
1. Remove the door as outlined under “OVEN DOOR”.
A. Remove the door strike plate from the top
B. Rotate the door 180°. The top of the door
C. Install the door strike on the new top of the
2. Remove the bottom door bushing and anti­rotation plate.
DISCONNECT THE ELECTRICAL
of the door.
is now the bottom.
door. Use the screws removed to install the strike plate to fill the holes on the bottom of the door.
7. Remove the door switch from the switch mounting bracket.
A. Use the other set of holes in the mounting
bracket to mount the switch.
B. Place the switch insulation pad on the
mounting bracket.
3. Remove the knockout from the lower sill cover.
4. Install the plug button in the old door bushing hole in the lower sill cover.
5. Install the bottom door bushing and anti­rotation plate.
6. Remove the catch assembly from the oven.
A. Move the door catch to the opposite side
of the door catch channel.
B. Install the door catch assembly to the
opposite side of the top sill.
C. Install the switch onto the mounting
bracket.
8. Install the door in the lower door bushing.
9. Install the top door bushing and door switch mounting plate to the new position on the upper sill.
10. Adjust the door as outlined under “DOOR ADJUSTMENT”.
11. Adjust the door switch as outlined under “DOOR SWITCH ADJUSTMENT”.
12. Replace the top front cover and check the oven for proper operation.
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HALF-SIZE GAS CONVECTION OVENS - SERVICE PROCEDURES AND ADJUSTMENTS
DOOR ADJUSTMENT
WARNING:
1. The door should be parallel with the face of the oven cav ity.
2. If adjustment is needed:
A. Remove the top front cover as outlined
B. Loosen the screws that secure the door
UNPLUG UNIT BEFORE SERVICING.
under “COVERS AND PANELS” in “REMOVAL AND REPLACEMENT OF PARTS”.
support and move the door in the slot until it is parallel with the face of the oven cavity.
BLOWER ADJUSTMENT
WARNING:
POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED.
1. Remove rack and rack supports.
2. Remove baffle panel by lifting up and out.
3. Check the blower. It should be ¼" away from and parallel to the oven wall. If not, proceed to step 4.
4. Remove the right side panel as outlined under “COVERS AND PANELS”.
5. To adjust the blower at the sides (front and rear of oven cavity), loosen the motor mounting bolts and move the motor until the ¼" gap is obtained.
6. To adjust the blower at the top and bottom, place shims between the motor mounting bracket and the mounting base.
DISCONNECT THE ELECTRICAL
C. Tighten the screws and install the top front
cover.
7. Reverse the procedure to install.
HEATING ELEMENT TEST
Test each rod in the element assembly. Values in the table are nominal (± 10%).
VOLTAGE W ATTS AMPS RESISTANCE
208 2500 12 17.33
240 2500 10.4 23.1
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
ELECTRICAL OPERATION
COMPONENT FUNCTION
POWER SWITCH .............Controls power to oven.
COOLDOWN SWITCH .........Prevents heaters from operating and allows fan to run. (On some solid state
control models, this switch is combined with the power switch)
FAN SPEED SWITCH .......... Controls speed of oven cavity blower motor. (Electric ovens)
SOLID STATE CONTROL.......Controls oven temperature.
TIMER .....................Signals end of timed baking. Does not shut heater or burner off. (Solid state
control)
ELECTRONIC CONTROL.......Controls oven temperature, cook and hold mode, pulse mode and time.
BLOWER MOTOR ............Circulates air inside oven cavity. (Contains centrifugal switch for gas ovens)
(2 speed electric ovens)
DOOR SWITCH ..............Allows heating of oven, only when the doors are closed.
TEMPERATURE PROBE ....... Senses temperature of oven cavity for the solid state control and electronic
control.
SOLID STATE RELAY ......... Controls power to blower motor. (Electronic Control)
TRANSFORMER.............. Provides 12 and 6 VAC power. (Electronic Control)
TRANSFORMER.............. Provides 24 VAC power to the spark ignition control if the centrifugal switch
(part of blower motor) is closed. (Gas Ovens)
GAS VALVE ................. Allows gas to flow to burner. (Gas ovens)
SPARK MODULE .............Generates spark for burner ignition, monitors flame, controls 15 second
purge time and 10 second ignition time and power to gas valve. (Gas ovens)
POWER LIGHT...............Lit whenever the power switch is ON. (Solid state control)
HEAT LIGHT.................Lit whenever burner or heaters are operating. (Solid state control)
NO IGNITION LIGHT ..........Lit when sensor fails to detect flame. (Solid state control - Gas oven)
CONTACTOR ................ Powers heater elements. (Electric ovens)
FUSE .....................Protects control circuit. (Electric ovens)
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
COMPONENT LOCATION
19
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
SEQUENCE OF OPERATION
Ignition Module
1. 24VAC supplied to ignition module as described under oven sequence of operation
A. 15 second prepurge period
1) No-ignition light is on
2) Cavity blower motor removes any residual gas from combustion chamber
B. 10 second spark period
1) Gas valve energized
2) No-ignition light is off
2. The flame is monitored by a DC voltage of at least 5 microamps passing from the ignitor probe through the flame to ground.
A. If the flame is detected before 10 seconds:
1) Sparking is terminated
2) Gas valve held open
3) Monitoring of flame continues
B. If a flame is not established after the 10
second spark period
1) a second 15 second prepurge period
2) A second 10 second spark period
C. If a flame is not established after the second
10 second spark period
1) a third 15 second prepurge period
2) A third 10 second spark period
D. If a flame is not established after the third 10
second spark period, the module will go into lock out
1) No ignition light on
Gas Oven
NOTE:
A combination of terminal numbers and wire numbers will be used to describe the circuit paths. The complete path will be described when a component is energized.
Solid State Control (Gas)
NOTE:
Use GCO2D Schematic
1. Conditions
A. Supply voltage to unit
1) L1 to power switch: wire #1; J1-1; wire #1
2) L2 to power switch: wire #2; J1-2; wire #2
3) Good chassis ground for: a. Ignition module: GND b. No ignition light: wire #48; GND;
wire #6; J1-6; wire #6; GND c. Gas valve: wire #48; GND; d. Ignition transformer: GND
B. Power switch off C. Oven at room temperature D. Temperature control off E. Manual gas valve open F. Door switch closed G. Cooldown switch off H. Timer off
2. Power switch turned "on" (voltage at terminals of power switch) A. Power On lamp lights: wire #34/J1; wire
#41/37
B. Control powered: wire #34; wire #33/3; J1-3;
wire #3; door switch; wire #27/4; J1-4; wire #4/36/35; terminal 8; terminal 9 (120 VAC) or terminal 10 (200-240 VAC); wire #39/37
C. Blower motor energized: wire #34; wire #33/3;
J1-3; wire #3; door switch; wire #27/4; J1-4; wire #4/11; J1-11; wire #11; wire #13/7; J1-7; wire #7/37
1) Blower motor reaches operating speed, blower motor centrifugal switch closes
3. To reset the ignition module perform one of the following A. Turn power switch off; then on
B. Open and close the door
C. Turn the temperature control all the way off
then back to the set temperature
4. If a flame is established then is extinguished before the temperature control is satisfied, the no ignition light will be on and the ignition module will attempt to light the burner in the sequence described above.
3. Control set to cook temperature, contacts 6/7 close
A. Ignition transformer primary powered: terminal
6; wire #9; J1-9; wire #9; BK/BL wire; WH/BK wire; wire #7; J1-7; wire #7/37
B. Heating lamp lights: terminal 6; wire #43; wire
#42/37
4. 24 VAC from ignition transformer secondary to ignition module: transformer secondary wire #52; centrifugal switch; wire #54; terminal 24V of control module; GND
5. Ignition module operates (see ignition module sequence of operation)
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
6. Temperature is satisfied and control contacts 6/7 open A. Heat light goes out. B. Power removed from ignition transformer.
7. Ignition module de-energized A. Gas valve de-energized, gas supply to burner
off.
8. Oven cycles on solid state control until power switch is moved from the "on" position or the door is opened.
NOTE:
The blower motor, heat lamp and gas valve are de-energized when the door is opened during the heat mode.
Solid State Timer (Gas)
NOTE:
Use GCO2D Schematic
NOTE:
The timer is not connected to the heating circuit and will not prevent the oven from heating when time expires.
1. Power switch on
2. Time dialed into timer, contacts 1/3 close.
A. Timer motor energized: wire #34/64; timer
contacts 1/3; wht wire; wire #37
3. Time expires.
A. Contacts 1/3 open
1) Timer motor de-energized
B. Contacts 1/4 close
4. Buzzer sounds: wire #34/64; timer contacts 1/4; wire
#66; wire #65/37
Electronic Control (Gas)
NOTE:
Use GCO2C Schematic
NOTE:
A combination of terminal numbers and wire numbers will be used to describe the circuit paths. The complete path will be described when a component is energized.
Heat
1. Conditions.
A. Supply voltage to unit.
1) L1 to power/cooldown switch: wire #1; J1-1; wire #1
2) L2 to: a. Motor: wire #2; J1-2; wire #2; J1-7;
wire #7/13
b. Primary of ignition transformer: wire
#2; J1-2; wire #2; J1-7; wire #7
c. Primary of control transformer: wire
#2; J1-2; wire #2; J1-7; wire #7/97
3) Good chassis ground: ignition module transformer a. Ignition module: GND b. Electronic control: terminal 8 of
control; J2-8; J1-6; wire #6; GND c. Gas valve: wire #48; GND d. Ignition transformer: GND
B. Power/cooldown “off". C. Oven at room temperature. D. Door switch closed. E. Manual gas valve open.
2. Power/cooldown switch turned "on"
A. Control transformer primary powered: wire
#26/4; J1-4; wire #4/94; wire #97/7; J1-7; wire #2; J1-2; wire #2; L2
5. Timer turned to off.
A. Contacts 1/4 open
1) buzzer de-energized
Cooldown (Gas/Solid State Control)
NOTE:
Use GCO2D Schematic
1. Conditions A. Oven temperature needs to be lowered. B. Power switch on
2. Cooldown switch on
A. Blower motor energized: power switch; wire
#34/33/36/11; J1-11; wire #11; wire #13/7; J1­7; wire #7/37; power switch
3. Control powered from secondary of control transformer:
A. 6 VAC - wire #16; J1-16; J2-3; J2-2; J1-15;
wire #15
B. 12 VAC - wire #14; J1-14; J2-1; J2-2; J1-15;
wire #15
4. Control set to desired temperature
A. Control verifies heat mode: 16 to 18 VDC
output on J2-11; J1-20; wire #20/21; power/cooldown switch; contacts of switch are open and no return voltage to J2-5
B. Control verifies that door is closed: 16 to 18
VDC output on J2-11; J1-20; wire #20/27; door switch; wire #3; J1-3; J2-4
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
5. After verification of heat mode and door closed:
A. Ignition transformer primary powered: wire
#26/43; J2-13; J2-15; J1-5; wire #5; BK/BL wire; WH/BK wire; wire #7; J1-7; wire #2; J1­2; Wire #2; L2
1) 24 VAC from secondary of ignition transformer to ignition module: wire #52; centrifugal switch; wire #54; terminal 24V of control module; GND
B. Solid state relay energized: 16 to 18 VDC
output on J2-11; J1-20; wire #20; wire #19; J1-19; J2-10
1) Blower motor energized: wire #26/4; J1-4; wire #4/34; ss relay contacts; wire #9; J1­9; wire #11; J1-11; wire #11; wire #13/7; J1-7; wire #2; J1-2; Wire #2; L2
a. Blower motor reaches operating
speed, blower motor centrifugal switch closes
6. Ignition module operates (see ignition module sequence of operation)
7. Oven cycles on electronic control until power/cooldown switch is moved from the "on" position, a different mode is selected or the door is opened.
NOTE:
The blower motor is de-energized and gas valve closed when the door is opened while the oven is in the heat mode.
Cook and Hold
1. Conditions
A. Oven in preheat.
2. A bake temperature and time is set.
3. A hold temperature and time is set and start key pressed.
4. Oven cycles at set temperature.
NOTE:
In pulse mode (initiated at the beginning of the bake cycle), the blower motor is operated in 45 second cycles, with the first cycle being off then 45 seconds on. The pulse time cannot be longer than the bake time.
5. Time expires in cook mode.
A. Buzzer sounds (short beep).
B. Control lowers temperature to hold
temperature.
6. Oven temperature reaches hold temperature.
A. Display counts up time and flashes "hold"
7. Oven continues to cycle at hold temperature until
oven is turned off or the hold function is turned off.
NOTE:
The blower motor and gas valve are de­energized when the door is opened while the oven is in the hold mode.
Cook
1. Conditions
A. Oven in preheat.
2. Temperature is set.
3. Time is set and start key pressed.
4. Oven cycles at set temperature.
NOTE:
In pulse mode (initiated at the beginning of the bake cycle), the blower motor is operated in 45 second cycles, with the first cycle being off then 45 seconds on. The pulse time cannot be longer than the bake time.
5. Time expires.
A. Buzzer sounds continually until turned off.
6. Oven continues to cycle at set temperature.
NOTE:
The blower motor and gas valve are de­energized when the door is opened while the oven is in the cook mode.
Cooldown (Gas/Electronic Control)
NOTE:
Use GCO2C Schematic
1. Conditions
A. Cooking completed, oven temperature needs
to be lowered.
B. Power/cooldown switch on
2. Power/cooldown switch to cooldown
A. Control transformer primary powered: wire
#26/4; J1-4; wire #4/94; wire #97/7; J1-7; wire #2; J1-2; wire #2; L2
3. Control powered from secondary of control transformer:
A. 6 VAC - wire #16; J1-16; J2-3; J2-2; J1-15;
wire #15
B. 12 VAC - wire #14; J1-14; J2-1; J2-2; J1-15;
wire #15
4. Control verifies cooldown mode: 16 to 18 VDC output on J2-11; J1-20; wire #20/21; power/cooldown switch; wire #29; J2-5
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
5. After verification of cooldown mode:
A. Solid state relay energized: 16 to 18 VDC
output on J2-11; J1-20; wire #20; wire #19; J1-19; J2-10
1) Blower motor energized: wire #26/4; J1­4; wire #4/34; ss relay contacts;; wire # 9; J1-9; wire #11; J1-11; wire #11; wire #13/7; J1-7; wire #2; J1-2; wire #2; L2
B. Contactor coil will not be energized. C. The door position signal is not read.
Electric Oven
NOTE:
A combination of terminal numbers and wire numbers will be used to describe the circuit paths. The complete path will be described when a component is energized.
Solid State Control (Elec)
NOTE:
Use ECO2D Schematic
1. Conditions.
A. Fuses are good.
B. Supply voltage to unit (three phase)
B. Control powered: wire #34; wire #33/3; J1-3;
wire #3; door switch; wire #27/4; J1-4; wire #4/36/35; terminal 8 and 7; terminal 9 (120 VAC) or terminal 10 (200-240 VAC); wire #39/37
C. Blower motor energized: wire #34; wire #33/3;
J1-3; wire #3; door switch; wire #27/4; J1-4; wire #4; motor speed switch; wire #11 high or 12 low ); J1-(11 high or 12 low); wire #(11 high or 12 low); wire #13/7; J1-7; wire #7/37
3. Control set to cook temperature contacts 6/7 close
A. Contactor coil energized: terminal 6; wire
#9; J1-9; wire #9/50; wire #52/7; J1-7; wire #7/37
B. Heating lamp lights: terminal 6; wire #43;
wire #42/37
4. Heating elements energized
A. L1; wire #61; C1; Wire #70; wire #75; C3; Wire
#64; L3
B. L1; wire #61; C1; Wire #74; wire #71; C2; Wire
#62; L2
5. Oven reaches set temperature and control contacts 6/7 open
1) L1 to power switch: wire #1; J1-1; fuse; wire #1A and one side of heater contacts C1: wire #61
2) L2 to one side of heater contacts C2: wire #62
3) L3 to power switch: wire #2; J1-2; fuse; wire #2A and one side of heater contacts C31: wire #64
4) Good chassis ground
C. Power switch "off"
D. Oven at room temperature
E. Solid state control off
F. Door switch closed
G. Fan speed switch in either position
H. Cooldown switch off
J. Timer off
2. Power switch turned "on" (voltage at terminals of power switch)
A. Power removed from contactor coil
1) Heating elements de-energized
B. Heating lamp goes out.
6. Oven cycles on solid state control until power switch is moved from the "on" position or the door is opened.
NOTE:
The blower motor and heating elements are de-energized when the door is opened and the oven is in the heat mode.
Solid State Timer (Elec)
NOTE:
Use ECO2D Schematic
NOTE:
The timer is not connected to the heating circuit and will not prevent the oven from heating when time expires.
1. Power switch on
2. Time dialed into timer, contacts 1/3 close.
A. Timer motor energized: wire #34/64; timer
contacts 1/3; wht wire; wire #37
3. Time expires.
A. Power On lamp lights: wire #34/J1; wire
#41/37
A. Contacts 1/3 open
1) Timer motor de-energized
B. Contacts 1/4 close
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
4. Buzzer sounds: wire #34/64; timer contacts 1/4; wire #66; wire #65/37
5. Timer turned to off.
A. Contacts 1/4 open
1) buzzer de-energized
Cooldown (Elec/Solid State Control)
NOTE:
Use ECO2D Schematic
1. Conditions
A. Cooking completed, oven temperature needs
to be lowered.
B. Power switch on
2. Cooldown switch on
A. Blower motor energized: power switch; wire
#34/33/36/ motor speed switch; wire #11 high or 12 low ); J1-(11 high or 12 low); wire #(11 high or 12 low); wire #13/7; J1-7; wire #7/37; power switch
Electronic Control (Elec)
C. Power/cooldown switch "off" D. Oven at room temperature E. Door switch closed F. Fan speed switch in either position
2. Power/cooldown switch turned "on"
A. Control transformer primary powered: wire
#26/4; J1-4; wire #4/94; wire #97/7; J1-7; wire #7/2A; fuse; J1-2; wire #2; L3
3. Control powered from secondary of control transformer:
A. 6 VAC - wire #16; J1-16; J2-3; J2-2; J1-15;
wire #15
B. 12 VAC - wire #14; J1-14; J2-1; J2-2; J1-15;
wire #15
4. Control set to desired temperature
A. Control verifies heat mode: 16 to 18 VDC
output on J2-11; J1-20; wire #20/21; J1-21; power/cooldown switch; contacts of switch are open and no return voltage to J2-5
B. Control verifies that door is closed: 16 to 18
VDC output on J2-11; J1-20; wire #20/27; door switch; wire #3; J1-3; J2-4
NOTE:
Use ECO2C Schematic
NOTE:
A combination of terminal numbers and wire numbers will be used to describe the circuit paths. The complete path will be described when a component is energized.
Heat
1. Conditions
A. Fuses are good.
B. Supply voltage to unit (three phase)
1) L1 to power/cooldown switch: wire #1; J1-1; fuse; wire #1A/1 and one side of heater contacts C1: wire #61
2) L2 to one side of heater contacts C2: wire #62
3) L3 to: a. Motor: wire #2; J1-2; fuse; wire
#2A/7; J1-7; wire #7/13
b. Contactor coil: wire #2; J1-2; fuse;
wire #2A/7; J1-7; wire #7/50
c. Primary of control transformer: wire
#2; J1-2; fuse; wire #2A/7; J1-7; wire #7/97
d. one side of heater contacts C3: wire
#64
4) Good chassis ground electronic control: terminal 8 of control; J2-8; J1-6; wire #6; GND
5. After verification of heat mode and door closed,
A. Solid state relay energized: 16 to 18 VDC
output on J2-11; J1-20; wire #20; wire #19; J1-19; J2-10
1) Blower motor energized: wire #26/4; J1­4; wire #4/34; ss relay contacts;; wire # (11 high or 12 low ); J1-(11 high or 12 low); wire #(11 high or 12 low); wire #13/7; J1-7; wire #7/37
B. Contactor coil energized: wire #43; J2-13; J2-
15; J1-5; wire #5; wire #50/7; J1-7; wire #7/2A; fuse; J1-2; Wire #2; L3
1) Heating elements energized a. L1; wire #61; C1; W ire #70; wire
#75; C3; Wire #64; L3
b. L1; wire #61; C1; W ire #74; wire
#71; C2; Wire #62; L2
6. Oven reaches set temperature
A. Power removed from contactor coil
1) Heating elements de-energized
7. Oven cycles on electronic control until power/cooldown switch is moved from the "on" position or the door is opened.
NOTE:
The blower motor and heating elements are de-energized when the door is opened and the oven is in the heat mode.
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
Cook
1. Conditions A. Oven has reached set temperature in heat
mode
2. Time is set and start key pressed.
3. Oven cycles at set temperature.
NOTE:
In pulse mode (initiated at the beginning of the bake cycle), the blower motor is operated in 45 second cycles, with the first cycle being off then 45 seconds on. The pulse time cannot be longer than the bake time.
4. Time expires. A. Buzzer sounds continually.
5. Oven continues to cycle at set temperature.
NOTE:
The blower motor and heaters are de­energized when the door is opened and the oven is in the cook mode.
Cook and Hold
1. Conditions
A. Oven has reached set temperature in heat
mode
2. A bake temperature and time is set.
3. A hold temperature and time is set and start key pressed.
4. Oven cycles at set temperature.
NOTE:
In pulse mode (initiated at the beginning of the bake cycle), the blower motor is operated in 45 second cycles, with the first cycle being off then 45 seconds on. The pulse time cannot be longer than the bake time.
Cooldown (Elec/Electronic Control)
NOTE:
Use ECO2C Schematic
1. Conditions
A. Cooking completed, oven temperature needs
to be lowered.
B. Power/cooldown switch on
2. Power/cooldown switch to cooldown
A. Control transformer primary powered: wire
#26/4; J1-4; wire #4/94; wire #97/7; J1-7; wire #7/2A; fuse; J1-2; wire #2; L3
3. Control powered
A. 6 VAC from secondary of control transformer -
wire #16; J1-16; J2-3; J2-2; J1-15; wire #15
B. 12 VAC from secondary of control transformer
- wire #14; J1-14; J2-1; J2-2; J1-15; wire #15
4. Control verifies cooldown mode: 16 to 18 VDC output on J2-11; J1-20; wire #20/21; power/cooldown switch; wire #29; J2-5
5. After verification of cooldown mode:
A. Solid state relay energized: 16 to 18 VDC
output on J2-11; J1-20; wire #20; wire #19; J1-19; J2-10
1) Blower motor energized: wire #26/4; J1­4; wire #4/34; ss relay contacts;; wire # (11 high or 12 low ); J1-(11 high or 12 low); wire #(11 high or 12 low); wire #13/7; J1-7; wire #7/37
B. Contactor coil will not be energized.
C. The door position signal is not read.
5. Time expires in cook mode.
A. Buzzer sounds (short beep).
B. Control lowers temperature to hold
temperature.
6. Oven temperature reaches hold temperature.
A. Display counts up time and flashes "hold"
7. Oven continues to cycle at hold temperature until oven is turned off or the hold function is turned off.
NOTE:
The blower motor and heating elements are de-energized when the door is opened and the oven is in the hold mode.
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
SCHEMATICS GAS OVENS
GCO2D
26
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GCO2C
HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
27
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
WIRING DIAGRAM - GAS
OVENS
GCO2D - Control Section
28
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
GCO2D - Oven Section
29
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
GCO2C - Control Section
30
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
GCO2C - Oven Section
31
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
SCHEMATIC-ELECTRIC OVENS ECO2D
32
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ECO2C
HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
33
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
WIRING DIAGRAM ELECTRIC OVENS
ECO2D - Control Section
34
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
ECO2D - Oven Section
35
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
ECO2C - Control Section
36
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
ECO2C - Oven Section
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HALF-SIZE CONVECTION OVENS - ELECTRICAL OPERATION
TROUBLESHOOTING
ELECTRIC OVENS
SYMPTOM POSSIBLE CAUSES
No power to oven controls. 1. Main breaker open.
2. Control circuit fuses open.
3. 12/6 volt transformer inoperative. (Electronic control)
No oven operation; power to controls. 1. Door switch open.
2. Temp. control malfunction.
Blower motor operates when oven is heating, but not in cooldown.
Blower motor does not operate, oven heats. 1. Door switch open or inoperative.
Oven is slow to heat or not hot enough. 1. Incorrect line voltage.
Oven temperature is too hot. 1. Thermostat or control not calibrated.
No heat; blower motor operates. 1. Thermostat or control inoperative.
1. Cooldown switch inoperative (solid state control).
2. Speed selection switch malfunction.
3. Blower motor inoperative.
4. Solid state relay malfunction. (Electronic Control)
5. Electronic control inoperative. (Electronic Control)
2. One phase of 3 phase out.
3. Thermostat or control malfunction.
4. Blower motor inoperative.
5. Contactor malfunction.
6. Temperature probe malfunction.
2. Thermostat or control malfunction.
3. Contactor inoperative.
2. Contactor malfunction.
3. Heaters open.
Electronic control does not function. 1. See "ELECTRONIC CONTROL" in "SERVICE
PROCEDURES AND ADJUSTMENTS".
Door does not seal or will not shut properly. 1. Doors out of adjustment.
2. Door seals inoperative.
3. Door catch malfunction.
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HALF-SIZE CONVECTION OVENS - TROUBLESHOOTING
GAS OVENS
SYMPTOM POSSIBLE CAUSES
No power to oven controls. 1. Unit unplugged
2. Power switch inoperative.
3. 12/6 volt transformer inoperative. (Electronic control)
No oven operation; power to controls. 1. Door switch open or inoperative.
2. Solid state relay malfunction. (Electronic control)
3. Blower motor malfunction.
4. Electronic control malfunction.
Gas does not ignite; no spark. 1. 24 volt transformer not functioning.
2. Spark ignition control inoperative or not grounded.
3. Solid state control or probe malfunction.
4. Electronic control or probe inoperative.
5. Centrifugal switch in blower motor inoperative.
Oven is slow to heat or not hot enough. 1. Gas pressure not correct.
2. Control malfunction.(solid state or electronic)
4. Probe inoperative.
5. Blower motor malfunction.
6. Check orifice.
Gas ignites, but will not maintain flame. 1. Insufficient gas pressure.
2. Flame sensor not positioned in flame.
3. Spark ignition control malfunction.
4. Check orifice.
Sparks but does not ignite. 1. Manual gas valve off.
2. Gas valve malfunction.
3. Spark ignition control inoperative.
Electronic control does not function. 1. See "ELECTRONIC CONTROL" in "SERVICE
PROCEDURES AND ADJUSTMENTS".
Door does not seal or will not shut properly. 1. Doors out of adjustment.
2. Door seals inoperative.
3. Door latch malfunction.
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Form 24575 (12/96) Printed in U.S.A.
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