Lennox EL180UH090E60C User Manual

Page 1
© 2013 Lennox Industries Inc.
EL180UHE(X)
Service Literature
Corp. 1302-L1
Revised 06-2013
EL180UHE(X) series units are mid-efficiency gas furnaces
used for upflow or horizontal applications only, manufac
tured with Lennox Duralokt heat exchangers formed of
aluminized steel. EL180UHE(X) units are available in heat
ing capacities of 44,000 to 132,000 Btuh and cooling ap
plications 2 to 5 tons. Refer to Engineering Handbook for
proper sizing.
Units are factory equipped for use with natural gas. Kits are
available for conversion to LP/Propane operation.
EL180UHE(X) model units are equipped with a hot surface
ignition system. The EL180UHE(X) unit meets the Califor
nia Nitrogen Oxides (NO
x
) Standards and California Sea
sonal Efficiency requirements. All units use a redundant
gas valve to assure safety shut-off as required by C.S.A.
All specifications in this manual are subject to change. Pro
cedures outlined in this manual are presented as a recom
mendation only and do not supersede or replace local or
state codes. In the absence of local or state codes, the
guidelines and procedures outlined in this manual (except
where noted) are recommended only and do not constitute
code.
TABLE OF CONTENTS
Specifications Page 2.............................
Blower Data Page 4..............................
Parts Identification Page 6.........................
I Unit Components Page 7........................
II Installation Page 20.............................
III Start Up Page 20..............................
IV Heating System Service Checks Page 20.........
V Typical Operating Characteristics Page 25.........
VI Maintenance Page 25..........................
VII Wiring and Sequence of Operation Page 28......
WARNING
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, person
al injury or loss of life. Installation and service must
be performed by a licensed professional HVAC in
staller (or equivalent), service agency or the gas sup
plier.
WARNING
Electric shock hazard. Can cause injury
or death. Before attempting to perform
any service or maintenance, turn the
electrical power to unit OFF at discon
nect switch(es). Unit may have multiple
power supplies.
WARNING
Sharp edges.
Be careful when servicing unit to avoid sharp edges
which may result in personal injury.

Lennox EL180UH090E60C Specifications

General

Model	EL180UH090E60C
Heating Capacity	90, 000 BTU
Efficiency Rating	80% AFUE
Fuel Type	Natural Gas
Stages	Single-Stage
Voltage	120V
Type	Gas Furnace
Blower Motor Type	Multi-Speed
BTU Output	90, 000 BTU/h

Summary

EL180UHE(X) Unit Overview and Safety

General Safety Warnings

Highlights critical warnings regarding installation, electrical hazards, and sharp edges.

Unit Specifications

Heating, Blower, and Electrical Specs

Details AFUE, Btuh, temp rise, gas pressure, blower specs, voltage, and overcurrent protection.

Installation Clearances

Specifies minimum clearances for upflow and horizontal installations by vent type and position.

Optional Accessories and Altitude Derate

High Altitude Derate Pressure Settings

Provides manifold and line pressure settings required for various altitudes and gas types.

Key Unit Components and Safety

Integrated Control (A92) and Precautions

Troubleshooting with LED Diagnostic Codes

Diagnostic Codes and Furnace Status

Lists LED flash codes and their corresponding diagnostic meanings for furnace operational status.

Heating System Component Functions

Flame Signal Measurement Procedure

Measuring Flame Signal with a Digital Meter

Ignitor Resistance and Voltage Testing

Ignitor Circuit Resistance Check

Provides two methods for checking ignitor resistance to verify circuit integrity.

Ignitor Voltage Supply Test

Details testing the 120VAC voltage supplied to the ignitor during its 20-second warm-up period.

Combustion Air Inducer Pressure Switch

Pressure Switch Functionality and Setpoints

Pressure Switch Troubleshooting and Testing

Blower Motor Service and Replacement

Blower Motor Electrical Checks

Motor Module Replacement and Testing

Motor Module Removal and Resistance Tests

Motor Module Installation and Drip Loop

Unit Installation, Start-Up, and Safety

Heating Start-Up and Shutdown Procedures

Guides through safe furnace start-up, emergency shutdown, and extended period shutdown protocols.

Heating System Service Checks and Gas Safety

Covers CSA certification, gas piping requirements, leak testing, and safety precautions.

Gas System Testing and Combustion Analysis

Gas Piping Leak Detection and Pressure Testing

Details leak detection methods, pressure testing, and gas flow measurement procedures.

Manifold Pressure and Combustion Quality Checks

Explains how to measure manifold pressure and analyze combustion for CO2 and CO levels.

Altitude Adjustments for Pressure and Kits

Electrical Ground and Voltage Verification

Line Neutral to 'C' Terminal Voltage Check

Line Hot to Line Neutral Voltage Check

Routine Furnace Maintenance Procedures

Preliminary Checks and Filter Service

Heat Exchanger and Burner Cleaning

Provides detailed steps for cleaning the heat exchanger, burners, and related components.

Component Removal and Reassembly

Wiring Diagram and Heating Sequence

Heating Sequence of Operation Explained

Details the step-by-step operational sequence of the furnace during a heating call.

Heating Sequence Troubleshooting - Part 1

Initial Heating Sequence Fault Diagnosis

Guides on diagnosing common heating issues using LED codes and initial checks.

Power, Ground, Polarity, and Voltage Checks

Details troubleshooting for power supply, grounding, polarity, and voltage issues affecting operation.

Heating Sequence Troubleshooting - Part 2

Ignition and Flame Sensing Faults

Addresses troubleshooting for ignitor, flame stabilization, and flame sensing issues.

Limit and Pressure Switch Fault Diagnosis

Details diagnosis for limit, rollout, and pressure switch faults, including watchguard modes.

Cooling Sequence Troubleshooting Guide

Cooling Sequence Fault Diagnosis

Outlines troubleshooting for cooling sequence failures, including LED codes and abnormal conditions.

Cooling Operation Checks and Rollout Switch

Covers checks for ground, polarity, voltage, and rollout switch status during cooling.

Continuous Fan Sequence Troubleshooting