Lennox EL297UH070XV36B User Manual

Page 1
UNIT INFORMATIONUNIT INFORMATION
Service Literature
©2016 Lennox Industries, Inc.
WARNING
Improper installation, adjustment, alteration,
service or maintenance can cause property damage,
personal injury or loss of life. Installation and service
must be performed by a licensed professional HVAC
installer (or equivalent), service agency or the gas
supplier.
CAUTION
As with any mechanical equipment, contact with
sharp sheet metal edges can result in personal
injury. Take care while handling this equipment and
wear gloves and protective clothing.
EL297UHV(X) series units are 90% e󰀩ciency gas furnac-
es used for upow or horizontal applications only, man-
ufactured with Lennox Duralok heat exchangers formed
of aluminized steel. EL297UHV(X) units are available in
heating capacities of 44,000 to 132,000 Btuh and cooling
applications up to 5 tons. Refer to Product Specications
Manual for proper sizing.
Units are factory equipped for use with natural gas. Kits
are available for conversion to LPG operation. EL297UH-
V(X) model units are equipped with the icomfort
®
enabled
SureLight
®
two-stage variable speed integrated control.
EL297UHV(X) unit meets the California Nitrogen Oxides
(NOx) Standards and California Seasonal E󰀩ciency re-
quirements. All units use a redundant gas valve to assure
safety shut-o󰀨 as required by C.S.A.
All specications in this manual are subject to change.
Procedures outlined in this manual are presented as a
recommendation only and do not supersede or replace lo-
cal or state codes. In the absence of local or state codes,
the guidelines and procedures outlined in this manual (ex-
cept where noted) are recommendations only and do not
constitute code.
TABLE OF CONTENTS
Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 2
Blower CFM Data . . . . . . . . . . . . . . . . . . . . . . . . . Page 5
I Unit Components . . . . . . . . . . . . . . . . . . . . . . . Page 26
II Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 57
III Start Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 79
IV Heating System Service Checks . . . . . . . . . Page 80
V Typical Operating Characteristics . . . . . . . . . Page 83
VI Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . Page 83
VII Wiring and Sequence of Operation . . . . . . Page 86
Program Unit Capacity Size Mode . . . . . . . Page 110
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . Page 111
EL297UHV(X)
100088
Communicating-ENABLED EL297UHV SERIES UNITS

Lennox EL297UH070XV36B Specifications

General

Model	EL297UH070XV36B
Efficiency Rating	97% AFUE
Heating Capacity	70, 000 BTU
Blower Type	Variable Speed
Fuel Type	Natural Gas
Vent Type	Direct Vent
Warranty	10-Year Limited Warranty on covered components, Lifetime Heat Exchanger Warranty
Ignition Type	Hot Surface Ignition
Type	Gas
Stages	Two-Stage

Summary

I- UNIT COMPONENTS

Control Box Components

Details on transformer, door interlock, circuit breaker, and integrated control within the control box.

Integrated Control (A92)

Information on the SureLight® two-stage, variable speed integrated control system.

Ignition Control Diagnostic Modes

Integrated Control DIP Switch Settings

B- Indoor Blower Motor

Blower Drive Operation and Troubleshooting

Details on blower drive, LED codes, motor components, and troubleshooting tests.

C- Heating Components

Ignitor and Flame Sensor

Information on the SureLight® ignitor and flame sensor, including checks.

II-PLACEMENT AND INSTALLATION

Condensate Piping

Instructions for installing and priming the condensate trap and drain lines.

III-START-UP

Heating Start-Up Procedures

IV-HEATING SYSTEM SERVICE CHECKS

Gas Piping and Testing

Proper Combustion and High Altitude

VII- Wiring and Sequence of Operation

Wiring Diagrams

Electrical diagrams illustrating furnace components and connections for various models.

Electronic Ignition and Heating Sequences

Details on electronic ignition and heating sequences for single/two-stage thermostats.

IX- Program Unit Capacity Size Modes

X- Troubleshooting

Heating Sequence of Operation Troubleshooting

Flowcharts and procedures to diagnose heating operation issues.

Cooling Sequence of Operation Troubleshooting

Flowchart and guidance for diagnosing cooling operation problems.