Lennox G23Q2/3-75 User Manual

INSTALLATION INSTRUCTIONS
 2000 Lennox Industries Inc.
Dallas, Texas, USA

INSTALLATION
INSTRUCTIONS
G23(X) SERIES UNITS
GAS UNITS
503,884M
1/2000
Supersedes 5/99
Table of Contents
Unit Dimensions 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts Arrangement 3. . . . . . . . . . . . . . . . . . . . . . . . . . .
Requirements 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Combustion, Dilution, & Ventilation Air 5. . . . . . . . . .
Installation - Setting Equipment 7. . . . . . . . . . . . . . . .
Return Air Opening Guidelines 7. . . . . . . . . . . . . . . . .
Filters & Optional Filter Assembly 8. . . . . . . . . . . . . .
Duct System 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Venting 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gas Piping 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrical 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unit Start-Up 21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gas Pressure Adjustment 22. . . . . . . . . . . . . . . . . . . .
High Altitude Information 23. . . . . . . . . . . . . . . . . . . . .
Other Unit Adjustments 23. . . . . . . . . . . . . . . . . . . . . .
Service 24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Repair Parts List 26. . . . . . . . . . . . . . . . . . . . . . . . . . . .
SureLight Troubleshooting 27. . . . . . . . . . . . . . . . . . . .
Start-Up & Performance Check List 31. . . . . . . . . . . .
RETAIN THESE INSTRUCTIONS
FOR FUTURE REFERENCE
WHAT TO DO IF YOU SMELL GAS:
Do not store or use gasoline or other
flammable vapors and liquids in the vi
cinity of this or any other appliance.
Installation and service must be per
formed by a qualified installer, ser
vice agency or the gas supplier.
 Do not try to light any appliance.
 Do not touch any electrical switch; do not use
any phone in your building.
 Immediately call your gas supplier from a
neighbor's phone. Follow the gas supplier's
instructions.
 If you cannot reach your gas supplier, call the
fire department.
 Extinguish any open flames.
If the information in this manual is not
followed exactly, a fire or explosion
may result causing property damage,
personal injury, or death.
WARNING
Litho USA

Lennox G23Q2/3-75 Specifications

General

Input BTU	75, 000
AFUE	80%
Output BTU/h	60, 000
Fuel Type	Natural Gas
Blower Type	Multi-speed
Weight	150 lbs
Ignition Type	Hot Surface Ignition

Summary

Safety Information

What to Do If You Smell Gas

Emergency steps to take immediately if a gas leak is detected.

Installation Requirements

Fiberglass Wool Safety

General Installation Guidelines

Combustion Air Requirements

Essential information on providing adequate air for combustion and ventilation.

Confined Space Ventilation

Guidelines for air supply in confined installation spaces.

Air Supply for Confined Spaces

Duct System and Venting

Venting Requirements

General rules and classifications for venting G23(X) furnaces.

Masonry Chimney Venting

Venting Configurations

Venting Tables and Guidelines

Vent Capacity Tables (Type B Double-Wall)

Vent Capacity Tables (Single-Wall Connectors)

Common Venting Capacity Tables

Gas Piping Installation

Gas Piping Requirements

Installation instructions, pipe sizing, and support for gas piping.

Leak Check

Procedures for detecting and verifying gas piping for leaks.

Gas Piping Capacity and Electrical

Electrical Wiring

Instructions for field make-up box, wiring, and grounding connections.

SureLight Integrated Control Board

Wiring Diagrams

Schematic Wiring Diagram

Typical Field Wiring Diagram

Unit Start-Up Procedures

Safety Before Lighting

Critical safety precautions to follow before initiating furnace operation.

Gas Valve Operation

Instructions on how to operate the gas valve for start-up and shut-down.

Gas Pressure Adjustment

Gas Flow Check

Gas Pressure Settings

Procedures for checking and adjusting gas line and manifold pressures.

Altitude and Unit Adjustments

High Altitude Information

Troubleshooting and Service

Failure to Operate Checklist

Heat Exchanger and Burner Cleaning

Heat Exchanger Cleaning Details

SureLight Troubleshooting (Heating)

Heating Sequence of Operation

Flowchart detailing normal and abnormal heating operation sequences.

SureLight Troubleshooting (Heating Cont.)

Heating Sequence of Operation Contd.

Continuation of the heating sequence flowchart for detailed diagnostics.

SureLight Troubleshooting (Cooling)

Cooling Sequence of Operation

Flowchart detailing normal and abnormal cooling operation sequences.

SureLight Troubleshooting (Fan)

Continuous Fan Sequence of Operation

Flowchart illustrating the operation of the continuous fan mode.

Start-Up and Performance Checklist

Checklist Items

A list of critical checks for unit start-up and performance verification.