Thermador Pro Grand Next Generation PRD48JDSGC/02 User manual

Service Manual for the Thermador Pro Grand Next Generation, Dual Fuel Range with Steam Oven, Models: PRD48JDSGC/02, PRD48JDSGU/02
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TABLE OF CONTENTS
1General .................................................................................................... 5
1.1 Technical Documents to Read Prior to Servicing.......................................... 5
1.2 Data Rating Plate.......................................................................................... 5
1.3 Wiring Diagram ............................................................................................. 6
1.4 Recommended Tools and Supplies .............................................................. 6
1.5 Important Safety Information......................................................................... 7
1.5.1 Safety Symbols Used In This Manual.................................................... 7
1.5.2 Safety Precautions to Know Prior to Servicing....................................... 7
2Operation and Controls ....................................................................... 11
2.1 Knobs and Controls..................................................................................... 11
2.1.1 Standard Burner Knob......................................................................... 11
2.1.2 ExtraLow (XLO) and ExtraHi (XHI) Burner Knobs................................ 11
2.1.3 Griddle / Grill Control Knob.................................................................. 11
2.1.4 Temperature / Function Selector Knob for Large Oven ....................... 11
2.1.5 Temperature / Function Selector Knob for Steam Oven...................... 11
2.1.6 Control Buttons for Warming Drawer................................................... 11
2.1.7 Oven Light and Panel Light Switches .................................................. 11
2.2 LED Indicators............................................................................................. 12
2.3 Automatic Re-Ignition.................................................................................. 12
2.4 Operation during a Power Outage............................................................... 12
2.5 Rangetop Burner Assembly and Maintop Components.............................. 12
3Testing, Adjusting, and Troubleshooting Rangetop Burners and
Ignition................................................................................................... 13
3.1 Before Testing............................................................................................. 13
3.2 Rangetop Burner Characteristics................................................................ 13
3.3 Rangetop Flame Characteristics................................................................. 14
3.4 Testing Rangetop Burner Ignition................................................................ 15
3.4.1 Time to Ignite....................................................................................... 15
3.4.2 Testing Ignition for Standard Burner Settings (HI, MEDIUM, SIM)....... 15
3.4.3 Testing Ignition for XLO Burner Settings.............................................. 15
3.5 Adjusting Rangetop Burner Valves Manually.............................................. 15
3.5.1 Special Tools Needed.......................................................................... 15
3.5.2 Adjusting the Bypass Screws............................................................... 16
3.6 Troubleshooting Burner, Flame, and Ignition.............................................. 16
3.6.1 Burner and Flame Diagnostics for Rangetop Burners.......................... 16
3.6.2 Ignition Diagnostics for Rangetop Burners........................................... 16
4Diagnostics for Elements, Temp Sensors, Warming Drawer, Steam
Oven, Oven Lights................................................................................ 18
4.1 Element Diagnostics ................................................................................... 18
4.1.1 Safety Practices for Element Diagnostics............................................ 18
4.1.2 Element Diagnostic Tips...................................................................... 18
4.1.3 Element Cycle/Circuit Specification ..................................................... 18
4.2 Oven Temperature Sensor Diagnostics...................................................... 18
4.2.1 Resistance and Temperature Values for Oven Temperature Sensor.. 19
4.3 Warming Drawer Diagnostics...................................................................... 19
4.3.1 Warming Drawer Architecture.............................................................. 19
4.3.2 Warming Drawer Fault Messages........................................................ 20
4.3.3 Warming Drawer Temperature Test..................................................... 20
4.3.4 Warming Drawer Troubleshooting ....................................................... 20
4.4 Steam Oven Diagnostics............................................................................. 22
4.5 Oven Light Diagnostics............................................................................... 22
5Fault Messages..................................................................................... 24
6Service and Repair ............................................................................... 25

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6.1 Preparing the Range for Servicing.............................................................. 25
6.2 Component Removal Videos ...................................................................... 25
6.3 Accessing Components under the Maintop................................................. 25
6.3.1 Removing Knobs, Grates, Burner Assemblies, Maintops, Heat Shields,
Burner Support Rails............................................................................ 25
6.3.2 Removing Maintops............................................................................. 27
6.3.3 Removing Heat Shields ....................................................................... 28
6.3.4 Removing the Burner Support Rail ...................................................... 28
6.4 Griddle / Grill Removal and Replacement................................................... 30
6.5 Side Panel Removal and Replacement....................................................... 32
6.6 Control Panel Removal and Replacement.................................................. 35
6.7 Removal and Replacement of Steam Oven Components........................... 37
6.7.1 Rack Supports for Steam Oven – Removal and Replacement ............ 38
6.7.2 Oven Lamp for Steam Oven – Removal and Replacement................. 38
6.7.3 Gasket for Steam Oven Door – Removal and Replacement................ 38
6.7.4 Steam Oven Control Board– Removal and Replacement.................... 39
6.7.5 Power Module for Steam Oven – Removal and Replacement............. 40
6.7.6 Actuator for Steam Oven – Removal and Replacement ...................... 41
6.7.7 Flap Components for Steam Oven – Removal and Replacement........ 42
6.7.8 Display Module Components and Oven Light Switch for Steam Oven –
Removal and Replacement.................................................................. 44
6.7.9 Temperature Sensor for Steam Oven – Removal and Replacement... 48
6.7.10 Temperature Limiter Assembly for Steam Oven – Removal and
Replacement........................................................................................ 49
6.7.11 Steam Oven Convection Components – Removal and Replacement.. 50
6.7.12 Evaporation Cup and Gasket – Removal and Replacement................ 52
6.7.13 Water Tank Housing and Funnel Assembly Components – Removal and
Replacement........................................................................................ 53
6.7.14 Reed Sensor Board – Removal and Replacement .............................. 55
6.7.15 Detaching the Funnel Assembly from the Tank Housing..................... 55
6.7.16 Servicing the Funnel Assembly Components....................................... 55
6.7.17 Steam Oven Door Hinge Receiver – Removal and Replacement........ 57
6.7.18 Steam Oven Door – Removal and Replacement of Glass with Drip-Tray
Assembly ............................................................................................. 58
6.8 Removal and Replacement of Warming Drawer Components.................... 59
6.8.1 Warming Drawer Control Panel Components – Removal and
Replacement........................................................................................ 59
6.8.1.1 Warming Drawer Door Handle Assembly – Removal and
Replacement................................................................................. 60
6.8.2 Warming Drawer Power LED Indicator – Removal and Replacement. 60
6.8.2.1 Warming Drawer Display Module – Removal and Replacement .. 61
6.8.3 Removing the Warming Drawer Front Panel........................................ 62
6.8.4 Removing the Warming Drawer Control Panel Assembly.................... 63
6.8.5 Removing the Warming Drawer and Cavity from the Range................ 64
6.8.6 Removing the Warming Drawer from the Cavity.................................. 66
6.8.7 Warming Drawer Sensor – Removal and Replacement....................... 68
6.8.8 Element Gasket and Frame – Removal and Replacement.................. 69
6.8.9 Microswitch and Glass Heating Element – Removal and Replacement70
6.8.10 Removing the Warming Drawer Slide Assembly.................................. 72
6.8.11 Warming Drawer Temperature Limiter – Removal and Replacement.. 73
6.8.12 Warming Drawer External Gasket – Removal and Replacement......... 75
6.9 Removal and Replacement of Top-Accessible Components...................... 76
6.9.1 Jet Holder Assembly Removal and Replacement................................ 76
6.9.2 Standard Valve Removal and Replacement........................................ 77
6.9.3 Microswitch Removal and Replacement.............................................. 78
6.9.4 Solenoid Valve Removal and Replacement......................................... 79
6.9.5 XLO Valve Removal and Replacement................................................ 80
6.9.6 Potentiometer Removal and Replacement .......................................... 81

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6.9.7 Manifold for Maintop Burners – Removal and Replacement................ 82
6.9.8 Regulator Removal and Replacement................................................. 84
6.9.9 Oven Lamp Transformer Removal and Replacement.......................... 85
6.9.10 Selector Switch for Oven Function and Oven Temperature – Removal
and Replacement................................................................................. 85
6.9.11 Oven Temperature Gauge Removal and Replacement....................... 86
6.9.12 Control Boards for the Large Oven – Removal and Replacement....... 87
6.9.13 Simmer Control Board Removal and Replacement ............................. 88
6.9.14 LED Indicator Removal and Replacement........................................... 89
6.9.15 Lighting Bar for Control Panel – Removal and Replacement............... 90
6.9.16 Ignition (Spark) Module Removal and Replacement............................ 91
6.9.17 Door Latch Removal and Replacement............................................... 91
6.9.18 Plunger Switch Removal and Replacement......................................... 94
6.9.19 Griddle / Grill Thermostat Removal and Replacement......................... 95
6.9.20 Display Module Components and Oven Light Switch for Large Oven –
Removal and Replacement.................................................................. 96
6.10 Removal and Replacement of Back-Accessible Components .................... 99
6.10.1 Backguard Removal and Replacement.............................................. 100
6.10.2 Back Panel for Steam Oven – Removal and Replacement................ 102
6.10.3 Back Panel for Large Oven – Removal and Replacement................. 102
6.10.4 Terminal Block and Power Cord – Removal and Replacement ......... 103
6.10.5 Electrical Wiring Connections at the Terminal Block.......................... 103
6.10.6 Cooling Fan Removal and Replacement ........................................... 103
6.10.7 Thermal Fuse Removal and Replacement......................................... 105
6.11 Removal and Replacement of Front-Accessible Components.................. 105
6.11.1 Oven Temp Sensor for Large Oven – Removal and Replacement.... 105
6.11.2 Meat Probe Receptacle Components – Removal and Replacement. 106
6.11.3 Rack Support Removal and Replacement......................................... 107
6.11.4 Oven Lamp Assembly and Bulb – Removal and Replacement.......... 108
6.11.4.1 Removing the Bulb ..................................................................... 109
6.11.4.2 Removing the Oven Lamp Assembly.......................................... 109
6.11.5 Oven Door Removal, Installation, and Alignment............................... 110
6.11.5.1 Removing the Door..................................................................... 110
6.11.5.2 Installing the Door....................................................................... 111
6.11.5.3 Aligning the Door........................................................................ 112
6.11.6 Large Oven Convection Components – Removal and Replacement. 112
6.11.7 Broil Element Components – Removal and Replacement................. 114
6.11.8 Bake Element Components – Removal and Replacement................ 117
6.11.9 Door Interior Cleaning........................................................................ 119
6.11.10 Large Oven Door Components – Removal and Replacement........... 120
6.11.11 Door Gasket Removal and Replacement........................................... 121
6.11.12 Kick Panel Removal and Replacement.............................................. 121
7Before Returning Appliance to Service............................................ 122
8Clean-Up.............................................................................................. 122
9Additional Resources......................................................................... 123
9.1 QuickFinder............................................................................................... 123
9.2 Technical Support..................................................................................... 123

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1 GENERAL
This manual contains information that is necessary for servicing the
following Thermador Pro Grand, Next Generation (PGNG) dual fuel
ranges with steam oven:
PRD48JDSGC/02
PRD48JDSGU/02
NOTE: Thermador Pro Grand Next Generation dual fuel ranges with
steam oven use natural gas (NG), however they can be converted for
use with Liquid Propane (LP) gas using the LP Conversion kit.
Due to the complexity and the risk of high-voltage electrical shock,
customers should not service their appliances.
The information provided in this document is intended for trained,
qualified personnel only. The proper function and the safety of the
appliance can be affected by an improper repair, and even serious
threats to life or physical condition may arise. BSH Home Appliances
Corporation is not liable for damages caused by improper repairs
performed by unauthorized parties. Local codes and standards apply
and must be observed.
For authorized servicers, additional assistance is available by
contacting our Technical Support Team at [phone].
1.1 Technical Documents to Read Prior to Servicing
Before you start servicing, check QuickFinder for all documents and
information associated with this specific appliance and/or parts.
1.2 Data Rating Plate
The data rating plate shows the model, serial, and FD number. It is
located at the right side panel (see Figure 1), and is pulled out by the
tab. The information on the data rating plate is required when calling
for technical or customer service.
The first two digits of the FD number indicate the year the appliance
was produced. To get the year, add 20 to the first two digits (for
example, an FD number beginning with 87 was produced in 2007; a
number that begins with 88 was produced in 2008). The last 2 digits of
the FD number indicate the month the product was produced (for
example, 06 indicates the appliance was produced in June).
Figure 1: Data Rating Plate

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1.3 Wiring Diagram
The wiring diagram is located on the back side of the kick panel
(see Figure 2).
Figure 2: Wiring Diagram Location
1
Kick panel (wiring diagram located on back side)
1.4 Recommended Tools and Supplies
The following are recommended to use when servicing this appliance:
mCaution
Power Drivers
If using a power driver, set the clutch to the lowest setting
üFlat blade screwdrivers: large, small
üPrecision flat-blade screwdriver with a high-strength blade,
1/8 inch (3.0 mm) wide, .020 inch (0.50 mm) thickness tip
üDrivers: T-10, T-20, T-27, T-30
ü2 foot long rachet extension
üRachet with 6-inch long (min.) swivel head extension
ü6 inch long (min.) flex extension
ü5/16 inch deep-well socket
ü1/4 inch nut driver
üAdjustable wrenches (2)
üStrap wrench
üOpen-end wrench sizes: 1/4 inch, 9 mm, 11 mm, 1/2 inch,
9/16 inch, 5/8 inch, 3/4 inch, 5/16 inch
üPipe wrench
üNeedle-nose pliers
üClean putty knife
üProtective gloves
üGas leak test equipment
üPipe sealant
üSmall mirror
üAir lifter / air dolly
üFloor protection
üProtective eye wear (such as glasses, goggles)
üFlashlight
üAmp meter
üThermometer with thermocouple leads
üMultimeter
üClean, non-abrasive cleaning cloth & flexible brush

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1.5 Important Safety Information
Before starting to service an appliance, familiarize yourself with all
safety information and precautions contained in this manual.
1.5.1 Safety Symbols Used In This Manual
Warnings alert you to dangers that may result in bodily injury or death.
mCaution
Cautions alert you to actions that may result in damage to the product,
or property.
1.5.2 Safety Precautions to Know Prior to Servicing
Before You Start Servicing the Appliance
Before disassembly, removal or installation of any component, do the
following:
■Turn off electrical power by removing the power cord from the
electrical outlet, and putting the circuit breaker in the OFF position
(or removing the fuse)
■Turn off the gas supply to the appliance
■Make sure the range and components are cool before removing or
servicing them
■Wear protective clothes: long sleeves, gloves, safety glasses
Replacement Parts
Use only authorized replacement parts for this appliance. Use of
substitutions may defeat compliance with safety standards set for
home appliances, will void the warranty, and may create safety
hazards resulting in bodily injury, death, or damage.
Fire / Explosion Hazards
■Make sure the gas valve at the wall is closed before removing and
installing any gas components.
■Do not store or use any flammable vapors, liquids, or combustible
materials in the vicinity of this appliance.
■Do not use water on grease fires. Turn appliance off and smother
the fire with baking soda or use a dry chemical or foam-type
extinguisher.
Griddle / Grill Hazard
The griddle / grill plate must always be correctly in place when it is on.
What to Do If You Smell Gas
■Turn off the electrical power supply (at the circuit breaker), but do
not touch any electrical switch on the appliance
■Shut off gas supply to the appliance
■Do not try to light this or any other appliance
■Do not create or use an open flame or spark
■Do not use any phone or cell phone in the building
■Installation and service must be performed by a qualified installer,
service agency, or the gas supplier.

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Testing for Gas Leaks
■Do not ever use a flame to test for gas leaks, as doing so may
result in explosion, injury, death, and/or damage to the appliance
and property.
■With electrical power off, carefully check for gas leaks at each gas
component that was removed, replaced, or otherwise serviced
using a gas leak detector (electronic leak detectors are highly
recommended) or bubble test. The only exceptions that may
require the electrical power to be on are for the XLO valves – for
these, use extreme caution when performing gas leak testing.
Electrical Hazards
■Before servicing the appliance, remove electrical power by
disconnecting the power cord from the wall receptacle, by shutting
off the circuit breaker, or by disconnecting the proper fuse.
■If tests have to be conducted while the appliance is live, always
use a residual-current-operated circuit-breaker. The protective
conductor connection must not exceed the recommended values.
■When repairs are complete, perform a function test in accordance
with the appropriate regulations.
■Do not under any circumstances cut or remove the separate
ground wire or the third (ground) prong from the power cord plug.
■Improper grounding or reverse polarization will cause malfunction
(such as continuous sparking of the igniters), which can damage
the appliance and create an electrical shock hazard. Make sure
the circuit is properly grounded and polarized in accordance with
applicable local codes and ordinances. Receptacle replacement
shall be in accordance with the National Electric Code.
Hot Surfaces
To avoid burns and injury, do not handle components and surfaces
that are hot, such as the rangetop burner assemblies, maintop,
griddle/grill, gas burners, electric elements, hot surface igniters, heat
deflector, and interior oven surfaces, or the exterior area immediately
surrounding the door.
Sharp Components
This appliance has sheet metal and other components which often
have sharp edges. When working on this appliance, avoid cutting
yourself and other injury by handling these parts with care and using
adequate protective measures, such as gloves.
In Case of Power Outage
■When there is a removal of electrical power, the XLO / XHI
burners and griddle cannot be used. Do not attempt to light them
manually during a power outage.
■If for any reason a control knob is on when there is any failure or
removal of electrical power from the appliance (such as a power
outage), immediately turn all control knob(s) to the OFF position.
■Ventilate by opening a door or window, and wait at least 5 minutes
for all the gas to dissipate.
■If you smell gas, refer to the applicable safety precautions stated
in this manual.

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Clean-up Hazards
■Don’t allow any cleaning or polishing solutions/compounds,
disinfectants or bleaches to remain in contact with the stainless
steel surfaces for long periods, or after clean-up. These may
contain chemicals or materials which could release harmful
inhalants and can damage the appliance. After cleaning or
polishing, always rinse the cleaning/polishing materials with clear
water and wipe dry with a clean soft, non-abrasive cloth.
■Never use bleach-containing or chlorinated cleaners, as they act
as oxidizers on metal surfaces.
■Clean the range with caution. Do not use flammable cleaners to
clean the range. Avoid steam burns; do not use a wet sponge or
cloth to clean the range while it is hot. Do not use any type of
aerosol cleaner on or around the rangetop when hot. Some
cleaners produce noxious fumes if applied to a hot surface. Follow
directions provided by the cleaner manufacturer.
Fiberglass Insulation
Wear gloves when handling fiberglass insulation.
Oven Door, Oven Accessories and Oven Gasket
■Use caution when opening the oven door during or immediately
after operation. Stand to the side of the oven when opening an
oven door to allow hot air or steam to escape. Keep face well
away from the open door to avoid injury.
■Before self-cleaning an oven, remove the broiler pan, oven racks,
temperature probe, any utensils, as well as excessive spillage.
■Do not clean, rub, damage, move, or remove the door gasket, as it
is essential for providing a tight seal during oven operation. If the
gasket becomes worn or excessively soiled with food particles,
replace the gasket.
Backguard Ventilation
■To ensure sufficient airflow for proper oven performance, do not
block or obstruct the vents located on the backguard (high
backguard, lowback, or island trim).
■Backguard vents and surrounding areas are hot. Do not place
plastic, other heat-sensitive items, or flammable / combustible
materials on or near the backguard vents, as these areas could
melt or ignite.
■Don’t touch or clean the backguard vent area while the appliance
is on, nor for several minutes after the appliance is turned off, to
prevent burning yourself.

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Prior to Returning Appliance to Service
Prior to returning the appliance to service, make sure that:
■All electrical connections are correct and secure
■All safety grounds (internal and external) are correctly and
securely connected. Be sure to use a multimeter.
■All gas connections are secure and have been leak tested using a
gas leak detector or bubble test
■All panels and components are properly and securely
reassembled
mCaution
Code Compliance
Local codes vary. Installation, electrical connections, gas connections,
and grounding must comply with all applicable codes.
TESTED IN ACCORDANCE WITH ANSI
Z21.1, THE STANDARD FOR HOUSEHOLD
COOKING GAS APPLIANCES. IN CANADA
TESTED IN ACCORDANCE WITH
CAN/CGA1.1 – M81, THE STANDARD FOR
DOMESTIC GAS RANGES.
Check your local building codes for the proper
method of installation. In the absence of local
codes, this unit should be installed in accordance
with the National Fuel Gas Code No. Z223.1/
NFPA 54 current issue and the National
Electrical Code ANSI/NFPA No. 70 current issue
or the Can – B149 Installation Codes for Gas
Burning Appliances and C22.1 Canadian
Electrical Code Part 1.
It is the responsibility of the owner and the
installer to determine if additional requirements
apply in specific installations.

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2 OPERATION AND CONTROLS
2.1 Knobs and Controls
The control knobs each have an icon to identify the burner location.
2.1.1 Standard Burner Knob
1. Press a control knob in, and turn counter-clockwise to HI setting.
The igniter for the burner clicks while sparking until flame ignition.
Burner should ignite within 4 seconds.
2. For the standard burners, rotate the knob to any setting between
the three markers for HI,MED, and SIM.
2.1.2 ExtraLow (XLO) and ExtraHi (XHI) Burner Knobs
XLO and XHI knobs can be set anywhere between the XLO and XHI
markings for a variable range of heat – from 105° F (for XLO) to 185°
F (for XHI).
The burners that have XLO functionality are:
•Left, front
•Left, rear
•Right, front
•Right, rear
The burner at the right, front has XHI functionality (in addition to XLO).
When in XLO mode (the very lowest flame setting), the flame cycles
on for approximately 8 seconds and then turns off for 52 seconds of
each minute.
■Press a control knob in, and turn counter-clockwise to HI or XHI.
The igniter for the burner clicks while sparking until flame ignition.
Burner should ignite within 4 seconds.
2.1.3 Griddle / Grill Control Knob
The griddle / grill knob controls the temperature to the griddle or grill,
from 150° F to 500° F.
■Press and turn the knob clockwise to select a setting.
NOTE: The griddle preheat time (the time from when the griddle is
turned on until the preheat light goes off) will vary according to
ambient (room) temperature and the level of electrical service. To
preheat the griddle to 350° F may take approximately 10 to 14
minutes.
2.1.4 Temperature / Function Selector Knob for Large Oven
The Temperature/Function Selector Knob for the large oven enables
selecting a temperature from 150° F to 500° F, as well as one of the
oven function modes.
NOTE: Warm setting displays WARM, which is about 150° to 175° F.
■Rotate the outer dial to select a cooking mode, and then rotate the
inner knob to select the temperature.
2.1.5 Temperature / Function Selector Knob for Steam Oven
The Temperature/Function Selector Knob for the steam oven enables
selecting a temperature from 150° F to 450° F, as well as one of the
steam oven function modes.
■Rotate the outer dial to select a cooking mode, and then rotate the
inner knob to select the temperature.
2.1.6 Control Buttons for Warming Drawer
Warming drawer control buttons on the warming drawer control panel
(LOW, MEDIUM, and HIGH) provide heat ranging from 120° F to
160° F.
2.1.7 Oven Light and Panel Light Switches
There is a toggle switch for each oven light, as well as for the panel
light.

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2.2 LED Indicators
When a burner is lit, its blue LED indicator is illuminated.
2.3 Automatic Re-Ignition
Each rangetop burner has its own electronic igniter that sparks when
the burner is turned on. If one or more burner blows out, the
respective igniter/electrode automatically re-ignites the flame.
2.4 Operation during a Power Outage
mCaution
Power Outage Precautions
■When there is a removal of electrical power, the XLO / XHI
burners and griddle cannot be used. Do not attempt to light them
manually during a power outage
■If for any reason a control knob is on when there is any failure or
removal of electrical power from the appliance (such as a power
outage), immediately turn all control knob(s) to the OFF position.
■Ventilate well by opening a door or window, and wait at least five
minutes until all the gas dissipates.
■If you smell gas, comply with the warnings and precautions in the
Important Safety Information section (page 7) of this manual.
2.5 Rangetop Burner Assembly and Maintop
Components
Figure 3: Rangetop Burner Assembly and Maintop Components
1
Electrode (Igniter)
2
Burner cap
3
Burner base
4
Venturi tube
5
Burner pedestal
6
Jet holder assembly
7
Wire guard clip
8
Burner support rail
9
Heat shield
10
Maintop

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3 TESTING, ADJUSTING, AND TROUBLESHOOTING
RANGETOP BURNERS AND IGNITION
Servicing Rangetop Burners and Ignition
Burner and ignition servicing must be performed by a qualified
technician. Improper adjustments may be dangerous, cause damage
or harmful by-products, and may void the appliance warranty.
Ignition Hazard
Do not touch burners when the igniters are active (sparking).
3.1 Before Testing
Before testing rangetop burners and ignition, do the following:
1. Reinstall any loose components that may have been removed
earlier, such as burner caps, griddle, and grates. Be certain that
burner caps seat properly into the burner bases, burner bases and
Venturi tubes are aligned correctly, and that the ignition wires are
properly positioned.
2. To test for gas leaks, make sure the electrical power is removed
and the manual gas shut-off valve is open, and then carefully
check range components and gas supply for leaks using a gas
leak detector or bubble test.
3. After gas checks are complete and before testing, connect the
range to the electrical power supply.
3.2 Rangetop Burner Characteristics
If one or more rangetop burner blows out, the respective igniter
electrode automatically re-ignites the flame.
The flame should burn through each burner port, completely around
the burner cap (see Figure 4).
Figure 4: Burner Ports
1
Burner ports
It is normal to hear the following during burner operation:
•A slight sound that is associated with gas combustion and ignition.
There should not be a loud noise.
•A clicking noise every time the gas cycles, coming from the
solenoid valves of the two left or two right burners.
•If using LP gas, a slight “pop” sound may be heard at the burner
ports a few seconds after the burner has been turned off.

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3.3 Rangetop Flame Characteristics
Natural gas: The rangetop burner flame color should be blue with no
yellow on the tips (see Figure 5). It is not uncommon to see orange in
the flame color; this indicates the burning of airborne impurities in the
gas, and will disappear with use. See Figure 6 for additional flame
characteristics.
LP gas: Slight yellow tips on the primary flame cone are normal and
may appear after a few minutes. The flame should be stable with no
excessive noise or fluttering. Orange colored streaks in the flame are
produced from burning airborne debris, which is normal at startup,
and should dissipate in a few minutes (see Figure 6).
When the flame is properly adjusted, it should burn completely around
the burner cap, at each burner port (see Figure 4, page 13).
Figure 5: Correct Flame Color and Characteristics
1
Dark blue
2
Secondary cone
3
Light blue
4
Primary cone
Figure 6: Additional Flame Characteristics
NOTE: If rangetop burner/flame characteristics are not adequate, see
Troubleshooting Burner, Flame, and Ignition,page 16).

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3.4 Testing Rangetop Burner Ignition
Ignition Hazard
Do not touch the rangetop burners when the igniters are sparking.
3.4.1 Time to Ignite
For each burner, push the control knob in and then turn counter-
clockwise to the highest setting. The igniter should produce a clicking
sound as the burner is sparking, and the burner should light within 4
seconds.
NOTE: It is normal for the burner to spark when a knob is pressed in,
or turned slightly.
3.4.2 Testing Ignition for Standard Burner Settings (HI,
MEDIUM, SIM)
Set the burner knob to HI, and observe flame characteristics
(see Figure 5 and Figure 6). If any burner flame burns primarily
yellow, verify if the burner cap is positioned properly on the burner
base, and then re-test. Repeat test for MEDIUM and SIM settings.
If flame characteristics do not improve, call Thermador technical
support at [phone].
3.4.3 Testing Ignition for XLO Burner Settings
Set the burner knob to XLO and observe if the flame cycles correctly.
It should be on for approximately 8 seconds, and then off for
approximately 52 seconds of each minute.
3.5 Adjusting Rangetop Burner Valves Manually
Although pre-adjusted, if you need to set the valves for the lowest
possible flame setting, then manually adjust the bypass screws on the
valves.
Figure 7: Bypass Screw on Valve (View with Control Panel Removed)
1
Bypass screw on all valves
3.5.1 Special Tools Needed
To reposition the bypass screws for minimum flow settings on manual
valves, use a precision high-strength blade screwdriver, with a 1/8
inch (3.0 mm) wide, .020 inch (0.50 mm) thickness tip.

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3.5.2 Adjusting the Bypass Screws
mCaution
Potentiometer Failure
Failure to turn off electrical power when adjusting bypass screws may
cause failure of the potentiometers
1. Turn off electrical power by unplugging the power cord, or putting
the circuit breaker in the OFF position.
2. Remove knobs from valve stems by slowly pulling knobs straight
out, away from control panel.
3. Remove and retain the right bezel mounting screw.
4. To engage the valve screw, insert the precision screwdriver with a
1/8 inch blade into the same hole in the bezel that was created by
the removal of the right side mounting screw.
5. Turn the valve screw clockwise just until "bottom out" position is
reached. Do not over-tighten the valve screw.
NOTE: XLO valves must be set to the XLO position for proper
access to the valve screw through the clearance hole in the
potentiometer.
NOTE: The griddle / grill is electric, controlled by a thermostat
which does not have a valve that requires adjustment.
Gas Leaks
With electrical power off, carefully check for gas leaks at each gas
component that was removed, replaced, or otherwise serviced using a
gas leak detector (electronic leak detectors are highly recommended)
or bubble test. For non- standard (XLO) valves, the electrical power
may need to be on when testing. Use extreme caution when
performing gas leak testing on XLO valves.
3.6 Troubleshooting Burner, Flame, and Ignition
3.6.1 Burner and Flame Diagnostics for Rangetop Burners
If a rangetop burner clicks (sparks) constantly or if burner doesn’t light
correctly and/or has inadequate burner/flame characteristics (per
Rangetop Burner Characteristics, page 13 and Rangetop Flame
Characteristics, page 14), then do the following:
üCheck if manual shut-off valve is open and unit is receiving gas
üCheck if the burner cap is properly aligned on the burner base
üCheck if the burner port is open and not clogged or blocked
üCheck if the igniter electrode is free from debris and is sparking
üIf it is suspect that air is in the gas supply lines and system, you
can purge the remaining air by operating one of the burners for
several minutes
üCheck if a fuse has blown or a circuit breaker has tripped
üCheck polarity
üFor constant sparking, check wiring connections at ignition (spark)
module and electrode, and also check grounding
üFor intermittent sparking, check the pot spacing, flame height, and
drafts in kitchen
üRefer to the Ignition Diagnostics,page 16
üCall Thermador technical support at [phone] for assistance
if any burners fail to light, or any burners continue to burn yellow
3.6.2 Ignition Diagnostics for Rangetop Burners
The following flowchart applies in the event a burner fails to ignite.
Before performing steps in the Diagnostic Flowchart for Rangetop
Burner Ignition (Figure 8, page 17), remove electrical power from
appliance during disassembly and during removal and installation
procedures. Restore electrical power when testing the unit if it is
reassembled.

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Figure 8: Diagnostic Flowchart for Rangetop Burner Ignition

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4 DIAGNOSTICS FOR ELEMENTS, TEMP SENSORS,
WARMING DRAWER, STEAM OVEN, OVEN LIGHTS
4.1 Element Diagnostics
Use the Element Cycle/Circuit Specification chart on this page for
troubleshooting all elements.
4.1.1 Safety Practices for Element Diagnostics
Observe all pertinent safety practices such as warnings, cautions and
instructions contained in the Safety Precautions to Know Prior to
Servicing section of this manual (page 7), throughout this manual, and
the Installation Manual. Ensure compliance with all applicable codes.
4.1.2 Element Diagnostic Tips
Wiring Diagram
üThe electrical wiring diagram is located behind the kick panel of
the range (see Wiring Diagram, page 6).
Resistance Reading
üYou can perform a resistance reading on an element with the
electrical power to the range turned off.
Amperage Reading for all Elements:
üFor an element, check either of the wires with an amp meter and
amp clamp.
üAlternatively, you can check the element from the corresponding
I/O relay terminals on the control board.
üAlternatively, you can check an element from the hot terminals
(L1, L2) and neutral terminal at the terminal block.
Temperature Reading
Do not remove the thermocouple prematurely when the oven is hot.
üUse a thermometer with a thermocouple leads to test the oven
temperature. If you leave the thermocouple in the oven during a
speed clean cycle, keep in mind it will take a few hours before the
oven is cool enough if you plan to retrieve the thermocouple.
4.1.3 Element Cycle/Circuit Specification
Cavity Cycle (Element/s) Mode Watts Volts Amps Ohms
Large
Bake (Bake element)
Active
2000
240
8.3
28.8
Large
Broil (Broil element)
Active
4000
240
16.7
14.4
Large
Convection Bake
(Bake, Broil, and Convection
elements are on during Preheat
mode. Only the Bake element
is on in Active mode, although
Broil element is on 4 seconds
of every minute for browning)
Preheat 8750 240 36.5 6.6
Active 2000 240 8.3 28.8
Large Convection Broil
(Bake, Broil, and Convection
elements are on for both
Preheat and Active modes)
Preheat 8750 240 36.5 6.6
Active 8750 240 36.5 6.6
Large
Speed Clean
(Bake, Broil, and Convection
elements are on)
Active 8750 240 36.5 6.6
N/A
Griddle (Griddle element)
Active
1600
120
13.3
9.0
Steam
Convection (conv. element)
Active
1800
240
7.5
32
Steam Steam + Convection
(convection element) Active 1800 240 7.5 32
4.2 Oven Temperature Sensor Diagnostics
With electrical power OFF, you can perform a resistance reading (and
simultaneous temperature reading) to check the warming drawer or
regular oven sensor. The resistance fluctuates according to ambient
(room) temperature.
To avoid injury, it is recommended to wait until the appliance at or
near room temperature before performing resistance and temperature
readings.

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4.2.1 Resistance and Temperature Values for Oven
Temperature Sensor
Degrees F Ohms
30 995
40 1016
50 1038
60 1059
70 1080
80 1101
90 1122
100 1143
110 1163
120 1184
4.3 Warming Drawer Diagnostics
Figure 9: Warming Drawer Element and Control Panel
1
Element (glass)
2
Control buttons and LEDs
3
Control panel (built-in the door)
Figure 10: Control Buttons and LEDs
4.3.1 Warming Drawer Architecture
Figure 11: Warming Drawer Architecture

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4.3.2 Warming Drawer Fault Messages
Warming drawer fault messages are indicated by the blue LEDs on
the warming drawer control panel. These fault messages will display
automatically (without having to be in test mode):
Fault Description State of LED Indicators
Temp sensor is shorted Medium and High LEDs flashing
Temp sensor is open or unplugged Medium LED is flashing
Runaway temp. (greater than 210° F) Hi and Medium LEDs are lit
Stuck key All LEDs are flashing
4.3.3 Warming Drawer Temperature Test
To access the warming drawer temperature test mode, press and hold
the Medium and High buttons down while simultaneously powering
up the range (either by plugging the range in, or by connecting the
multi-pin connector as shown in Figure 92, page 59). To exit the test
mode, remove power from the range. The following fault messages
correlate to the air temperature in the warming drawer during the test,
and they only display during test mode:
Fault Description
State of LED Indicators
Temperature greater than 206° F
High
LED is lit
Temperature between 193° F and 206° F Medium LED is lit
Temperature between 102° F and 193° F High LED is lit while Medium
and Low LEDs are alternating
Temperature between 97° F and 102° F Medium and Low LEDs are
flashing at the same time
Temperature between 52° F and 97° F Off LED is lit while Medium
and Low LEDs are alternating
Temperature between 47° F and 52° F Low LED is lit
Temperature less than 47° F Off LED is lit
Temp sensor is open or unplugged Off LED is flashing
Temp sensor is shorted High LED is flashing
4.3.4 Warming Drawer Troubleshooting
In addition to taking a temperature sensor resistance reading (see
Oven Temperature Sensor Diagnostics,page 18) and performing a
warming drawer temperature test (see Warming Drawer Temperature
Test, page 20), you can perform the following diagnostics for the
warming drawer:
1. Follow all safety precautions and steps in the Preparing the Range
for Servicing, page 25.
2. Pull to open the warming drawer, and from the back side of the
control panel remove and retain the four screw-and-washer sets
(see Figure 99, page 62).
3. Pull the control panel out slightly, and then from underneath the
warming drawer detach the multi-pin wire connector (see Figure
100 and Figure 101, page 63).
4. With the warming drawer closed, use a multimeter to check the
resistance across the two pins leading to the glass heating
element (or the respective two element terminals). See Figure 12.
Figure 12: Element Terminals
1
Terminals (2) on glass heating element

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5. On the female wire connector attached to the control panel (see
Figure 100 and Figure 101, page 63), locate the blue wire labeled
MAIN WARM-1 and the white wire labeled MAIN WARM-3. Then
on the male wire connector that’s attached to the warming drawer,
test the two pins that correspond to the blue and white wires.
6. If the multimeter shows some resistance value when performing
the test across the two pins, it means that the problem lies with
neither the microswitch nor the temperature limiters. In this case,
do the following:
•Check the connection to the control board from the blue wire
(MAIN WARM-1) and the white wire (MAIN WARM-3). See
Figure 100 and Figure 101, page 63.
•Check the control board by performing the Warming Drawer
Temperature Test procedure, page 20.
7. If the multimeter shows no resistance value when performing the
test across the two pins, it means there is an open circuit. In this
case, check the resistance by sliding the warming drawer open far
enough to reach underneath, and then with your hand, press on
the microswitch arm to close the circuit (see Figure 13).
8. If this shows resistance, then the microswitch is the problem.
9. If the circuit is still open when pressing on the microswitch arm,
then one of the temperature limiters must be the culprit. In that
case, test the resistance of each temperature limiter separately to
determine which one is faulty.
10. Press the reset button on the bottom of the manual temperature
limiter, and then test the resistance again.
NOTE: If the manual temperature limiter needs to be reset, it may
be due to the warming drawer being abnormally hot, which will
cause the temperature limiter to trip. Check the warming drawer
gasket for damage and replace as necessary.
Figure 13: Microswitch Arm (View from Bottom of Warming Drawer)
1
Slide assembly
2
Microswitch
3
Arm on microswitch
4
Back side of wire tray (under warming drawer)