TurboChef TORNADO Service Manual

The Oven Door

TurboChef TORNADO Specifications

General

Model	TORNADO
Ventilation	Ventless
Brand	TurboChef
Warranty	1 year parts and labor
Category	Oven
Interior Dimensions	16" W x 14.5" D
Power Requirements	208-240V
Cooking Modes	Microwave
Control Type	Touch control
Phase	1-Phase

Summary

Service Manual

IMPORTANT SAFETY INFORMATION

General Safety Information

Read all instructions before using the appliance. Install or locate this appliance only in accordance with the provided installation instructions.

Reducing Fire Risk

Remove wire twist-ties from paper or plastic bags used to facilitate cooking in the oven. If materials inside the oven ignite, keep oven door closed.

Introduction

Servicing Precautions for Microwave Energy

DO NOT operate or allow the oven to be operated with the door open. Make the following safety checks on all ovens to be serviced.

Grounding Instructions

This appliance must be grounded. In the event of an electrical short circuit, grounding reduces the risk of electric shock.

RF Interference Considerations

The NGC (Tornado®) oven generates radio frequency signals. This device has been tested and was determined to be in compliance.

Installation, Specifications, and Maintenance

Specs and Dimensions

Exterior and cook cavity dimensions, wall clearance, entry clearance, construction, interior details, and standard features.

Certifications

UL, cUL, NSF, FDA, FCC, TÜV, CE. UL KNLZ Ventless Certification.

Power Supply - North America

SMART VOLTAGE SENSOR TECHNOLOGY. Voltage: 208/240 VAC, 60 Hz, 1 phase. Amperage: Nameplate rating 30 Amp.

Power Supply - Europe, Asia-Pacific

Details NGC EW (3-phase), NGC ED (3-phase) Universal Voltage, and NGC UK (1-phase) power supply specifications.

Delivery and Product Placement

Instructions for checking for damage, removing packaging, and proper placement of the oven.

Lifting and Placing the Oven

Procedure for safely lifting and placing the oven on a countertop, emphasizing weight and two-person lift.

Installation Near Open Heat Source

Guidelines for placing the oven near heat sources, including required clearances and dividers.

Oven Restraint Kit

Optional system to prevent oven movement during use/cleaning. Not a fall prevention device.

Ventilation Requirements

Approved for ventless operation for most foods, but consult codes for 'fatty raw proteins'.

Stacking

Steps for securely stacking ovens, including surface requirements and using stacking brackets.

Daily Maintenance for the NGC

Cleaning instructions using TurboChef Oven Cleaner. Lists supplies needed and step-by-step guide.

Theory of Operation

Chapter 4: Control System

Lists components: I/O Control Board, Keypad, Display, Mechanical Relays, Solid State Relay.

Chapter 5: Microwave System

Lists components: Magnetrons, High Voltage Transformers, Filament Transformers, High Voltage Capacitors, High Voltage Diodes, Fuses.

Chapter 7: Convection System

Lists components: Convection Heater, Blower Controller, Blower Motor, Hi-Limit Thermostat.

Chapter 8: Bottom IR and CCV

Lists components: Bottom Infrared Element, Catalytic Converter.

Glossary of Common Operating Terms

Defines terms like Off State, Cool Down, Ready State, Set Temperature, Actual Temperature, Edit Mode, Warm-Up, Soak, Cook Cycle, Test Mode.

Keypad

The primary interface for the operator.

Display

Displays all visual information to the operator.

Self-Test (STEST)

A special diagnostic function that tests all critical subsystems to determine their operational state.

Fault Code

A code assigned to an instance that the control considers to be a failure. Displays description and logs faults.

Fault Codes

To View Fault Codes

Simultaneously press '4' and '6' keys while oven is in OFF STATE to view Fault Log.

Fault Code Definitions

Lists and defines fault codes F1 through F4.

F5: Magnetron Over Temperature

Fault displayed when magnetron thermostat is 'open'.

F6: EC Temperature High

Fault when EC thermocouple exceeds 158°F (70°C).

F7: Thermocouple Open

Fault displayed when control detects IR or CC thermocouple is 'open'.

F8: Heat Low

Displays during WARM UP or SELF TEST if cook cavity temp fails to rise.

The Control System

Safety Interlocks

Illustrates safety interlock switches (Monitor, Primary, Secondary) and their connections.

Control System Component Descriptions

Detailed descriptions of components like 24 VDC Power Supply, K1-K7 Relays, SSRs, Interlock Switches, Thermocouples, BMSC, VFD, Keypad, Voltage Sensor.

Test Mode

Allows technicians to operate subsystems individually and configure presets.

Test Function Options

Lists and describes various test functions for oven components.

Diagnostic Display (Screen 2)

Enables display of temperature and cook cycle parameters, and status indicators.

Status Indicators

Explains indicators (P, S, M, t, h, i, A, W) showing component status (open/closed, on/off).

Programming

Section covering oven programming features.

Altering a Recipe

Instructions for changing cook time, IR element temperature, and event parameters for recipes.

Loading a Menu from a Smart Card

Steps to load recipes and menus from a smart card into the oven.

Oven Options

Details various oven options like Done Screen, Time Screen, and Snooze Mode.

User Configurable Options - Enable/Disable Codes

Codes to enable/disable functions/screens like Done Screen, Edit Recipe Mode, Load Menu, Snooze Screen.

User Configurable Options - Access Codes

Codes to access functions like Edit Recipe Mode, Erase Menu, Load Menu, Master Reset, Test Mode.

Control System Panel Parts

Illustrates and lists parts for the control system panel enclosure, including covers, cables, and readers.

Control System Troubleshooting

Provides troubleshooting steps for common control system issues.

F1: Blower Running Status Bad

Troubleshooting for blower motor not running, checking voltage, wiring, and motor controller.

F3: Magnetron Current Low

Troubleshooting for low magnetron current, checking K2 relay and transformer.

F8: Heat Rise Low

Troubleshooting for oven not warming up, checking blower motor and high-limit thermostat.

F2: Cook Temperature Low

Troubleshooting for low cook temperature, checking high-limit thermostat and EMI problems.

The Microwave System

Voltage Doubler Circuit Description

Describes the microwave system components: magnetron and voltage doubler circuit.

Monitor Circuit Description

Explains the failsafe monitor circuit, interlocks, and F3 fuse operation.

Voltage Doubler Theory of Operation

Explains how the voltage doubler circuit steps up voltage and charges capacitor for magnetron operation.

Microwave System Parts

Lists parts for the microwave system, including HV Transformers and Capacitors.

Magnetron

Supplies RF energy at 2.45 GHz, outputs 1 kW of power.

High-Voltage Transformers

Ferro-resonant design, supplies high voltage for the Voltage Doubler Circuit.

Filament Transformers

Preheat magnetron filament, supply ~3.15 VAC at 10 amps.

F3 Fuse

20-amp fuse that blows for over-current or failsafe trips.

Wave Guide Cover Replacement

Instructions for removing and replacing wave guide covers to prevent contamination.

Wave Guide/Wave Guide Cover Parts

Lists parts for wave guide covers and covers themselves.

Wave Guide Replacement

Steps for removing and replacing wave guides, including the need for sealant.

Wiring the High-Voltage Transformers

Proper reinstallation of transformers, noting mirror opposite installation and 180° out-of-phase wiring.

Wiring the Filament Transformers

Instructions for straightforward, in-phase and in-line wiring of filament transformers.

Measuring RF Leakage for Microwave Safety

Procedure for testing RF leakage after service tasks like door or magnetron replacement.

Testing the High-Voltage Diode

Steps to test the high-voltage diode using a multimeter and 9-volt battery.

How to Check a Diode

Procedure for checking a diode's conductivity in one direction using a multimeter.

How to Check a Capacitor

Steps to check a capacitor's impedance and case continuity.

How to Check a Magnetron for Open/Shorted Filament

Procedure to check magnetron filament resistance and continuity to chassis.

How to Check a High-Voltage or Filament Transformer

Steps to check transformer winding impedance against a resistance table.

Magnetron Troubleshooting Guidelines

Warnings about testing voltages and capacitor discharge before servicing.

F3: Magnetron Current Low

Troubleshooting steps for low magnetron current, checking amperage and F3 fuse.

F3: Magnetron Current Low (cont.)

Continued troubleshooting for magnetron current low, checking transformer voltages and control signals.

F3 Fuse Blown

Reasons for F3 fuse blowing: HV transformer short, HV capacitor failure, or monitor circuit fault.

F3 Fuse Blown, cont.

Troubleshooting F3 fuse blown due to monitor circuit faults and interlock switches.

Mag 1 or Mag 2 Not Working or Food Not Cooking Evenly

Troubleshooting for magnetron issues, checking amperage and transformer energization.

High Voltage and/or Filament Transformer(s) Faulty

Troubleshooting faulty transformers by measuring winding resistances.

The Oven Door

Removing/Reinstalling the Oven Door

Steps to remove and reinstall the oven door, including hinge screw locations.

Oven Door Parts

Lists and illustrates parts for the oven door assembly, including hinges, screws, and latches.

Adjusting the Oven Door

Procedure to adjust the oven door for proper alignment and seal, including safety warnings.

Preparing the Oven for Switch Adjustment

Steps to prepare the oven for switch adjustment, including disconnecting power and ensuring door adjustment.

Adjusting the Primary and Secondary Interlock Switches - Old Switch Setup

Instructions for adjusting old switch assembly, identifying by serial number format.

Adjusting the Primary Interlock Switch - New Switch Setup

Steps to adjust primary switch for new setup, using shims for toggle position.

Primary and Secondary Interlock Switch Adjustments and Parts

Lists parts and steps for adjusting primary and secondary interlock switches.

Adjusting the Monitor Switch - Old Setup

Instructions for adjusting the monitor switch on the right hinge assembly for old setups.

Monitor Safety Switch Parts

Lists parts for the monitor safety switch.

Adjusting the Primary Interlock Switch - New Switch Setup

Steps to adjust primary switch for new setup, checking toggle position and switch gap.

Adjusting the Secondary and Monitor Interlock Switches - New Switch Setup

Steps to adjust secondary and monitor switches for new setup, verifying switch gaps and sequence.

Secondary and Monitor Safety Switch Parts

Lists parts for secondary and monitor safety switches.

Oven Door Assembly

Overview of oven door assembly, referencing figures for mis-adjustments.

Oven Door Parts

Lists and illustrates parts for the oven door assembly.

Critical Adjustment Notes (Figure 35)

Notes on gasket orientation, insulation attachment, and door flatness after tightening.

Screw Torque Chart

Table specifying torque values for various screws used in the oven door assembly.

Interlock Switch Troubleshooting

Troubleshooting common interlock switch issues.

The Convection Circuit

Convection Circuit Components

Lists and describes components within the convection circuit.

Main Convection Heater

Open-coil style heater rated at 3300 watts at 208 VAC.

Convection Motor

Brushless AC switch reluctance type, top speed 7100 RPM.

Motor Controller (BMSC)

Proprietary controller for the convection motor, controlled by I/O board.

High Limit Thermostat

3-pole, manual reset thermostat that interrupts power to heater and IR element.

Convection Circuit/Blower Motor Parts

Lists parts for the convection circuit and blower motor assembly.

Convection Circuit Troubleshooting

Troubleshooting steps for convection circuit issues.

F8: Heat Low

Troubleshooting for oven not warming up, checking blower motor and high-limit thermostat.

F2: Cook Temperature Low

Troubleshooting for low cook temperature, checking door operation and high-limit thermostat.

F1: Blower Running Status Bad

Troubleshooting blower motor status, checking motor spin, windings, and controller voltage.

Motor Winding Resistances Table

Table of expected resistance values for blower motor windings.

IR Element and Catalytic Converter

Components

Describes the IR Element and Catalytic Converter components.

IR Element

Dual coil heater located at bottom of cavity, outputs 3000 watts at 208 VAC.

Catalytic Converter

VOC type catalyst behind cavity wall for cleaning airflow, sensitive to chemicals.

IR Element and Catalyst Removal

Steps for removing the IR element and catalytic converter.

Removing the IR Element

Steps to remove the IR element, including disconnecting wires and removing snap rings.

Removing and Installing the Catalytic Converter

Steps to remove and install the catalytic converter, accessing it after IR element removal.

Installing a New IR Element

Steps for installing a new IR element, including connecting wires and reinstalling hardware.

IR Element and Catalytic Converter Parts

Lists parts for IR element and catalytic converter assembly.

Schematics and Schematic Components

Schematic Parts

Lists all schematic parts, categorized by voltage and function.

Line Voltage Components

Lists components related to line voltage like capacitors, motors, diodes, EMI filters, fuses, and heaters.

Wire Harness Replacement P/Ns

Part numbers for replacement wire harnesses (Low Voltage, Line Voltage, Magnetron Wire).

1/0 Control Board Item Identification and Test Point Locations

Identifies items and test points on the I/O control board.

I/O Board Schematic

NGC (US) Schematic

Safety Interlocks

Illustrates safety interlock switches (Monitor, Primary, Secondary) and their connections.

NGC (UK) Schematic

Safety Interlocks - New Setup

Illustrates safety interlocks for new setup, including switch connections.

Safety Interlocks - Old Setup

Illustrates safety interlocks for old setup, including switch connections.

NGC (EW) Schematic

Safety Interlocks - New Setup

Illustrates safety interlocks for new setup, including switch connections.

Safety Interlocks - Old Setup

Illustrates safety interlocks for old setup, including switch connections.

NGC (ED) Schematic

Safety Interlocks - New Setup

Illustrates safety interlocks for new setup, including switch connections.

Safety Interlocks - Old Setup

Illustrates safety interlocks for old setup, including switch connections.

NGC (BRAZIL) Schematic

Safety Interlocks New Setup

Illustrates safety interlocks for new setup, including switch connections.

Safety Interlocks Old Setup

Illustrates safety interlocks for old setup, including switch connections.

Service Parts and Illustrations

Control System Panel Enclosure and Parts

Illustrates and lists parts for the control system panel enclosure, including covers, cables, and readers.

Microwave System Parts

Lists parts for the microwave system, including HV Transformers and Capacitors.

Wave Guide Cover/Wave Guide Removal and Replacement

Instructions for removing and replacing wave guide covers to prevent contamination.

Oven Door Removal and Parts

Lists and illustrates parts for the oven door assembly, including hinges, screws, and latches.

Primary and Secondary Interlocks Adjustment and Parts - Old Switch Setup

Lists parts and steps for adjusting primary and secondary interlock switches.

Door Switch Assembly and Parts - Old Switch Setup

Lists parts for the door switch assembly.

Monitor Switch Adjustment and Assembly - Old Switch Setup

Instructions for adjusting the monitor switch on the right hinge assembly for old setups.

Primary Interlock Adjustment and Parts - New Switch Setup

Steps to adjust primary switch for new setup, using shims for toggle position.

Secondary and Monitor Switch Adjustment and Assembly - New Switch Setup

Steps to adjust secondary and monitor switches for new setup, verifying switch gaps and sequence.

Secondary and Monitor Safety Switch Parts

Lists parts for secondary and monitor safety switches.

Oven Door Assembly

Overview of oven door assembly, referencing figures for mis-adjustments.

Oven Door Parts

Lists and illustrates parts for the oven door assembly.

Convection Circuit Block Diagram

Diagram showing the components and connections within the convection circuit.

Convection Circuit Assembly and Parts

Lists parts for the convection circuit and blower motor assembly.

IR Element and Catalytic Converter Parts and Assembly

Lists parts for IR element and catalytic converter assembly.

Covers and Miscellaneous Parts - Non-SBK Ovens

Lists and illustrates parts for the non-SBK oven covers and miscellaneous components.

Covers and Miscellaneous Parts - SBK Ovens

Lists and illustrates parts for the SBK oven covers and miscellaneous components.

Comprehensive Part List