Lennox ML296UH045XV36B - User Manual

Page 1
© 2019 Lennox Industries Inc.
Corp. 1903-L1
ML296UHV(X)
Service Literature
ML296UHV(X) SERIES UNITS
ML296UHV(X) series units are 90% efficiency gas fur
naces used for upflow or horizontal applications only,
manufactured with Lennox Duralokt heat exchangers
formed of aluminized steel. ML296UHV(X) units are avail
able in heating capacities of 44,000 to 132,000 Btuh and
cooling applications up 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 LPG operation. ML296UHV(X)
unit meets the California Nitrogen Oxides (NO
x
) Standards
and California Seasonal Efficiency requirements. All units
use a redundant gas valve to assure safety shut-off as re
quired 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 recommendations only and do not consti
tute code.
TABLE OF CONTENTS
Specifications Page 2.............................
Blower Data Page 3..............................
I Unit Components Page 9........................
II Installation Page 21.............................
III Start Up Page 43..............................
IV Heating System Service Checks Page 44.........
V Typical Operating Characteristics Page 47.........
VI Maintenance Page 47..........................
VII Wiring and Sequence of Operation Page 50......
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.
CAUTION
As with any mechanical equipment, contact with
sharp sheet metal edges can result in personal in
jury. Take care while handling this equipment and
wear gloves and protective clothing.

Summary

SPECIFICATIONS

I- UNIT COMPONENTS

3. Integrated Control (A92)

Information on the two-stage, variable speed integrated control with diagnostics.

C- Heating Components

7. Combustion Air Inducer (B6) and Cold End Header Box

Describes the two-stage inducer, its operation, and the cold end header box.

8. Combustion Air Inducer Pressure Switch (S18)

Explains the dual pressure switch for proving inducer operation and safety.

4. Flame Rollout Switches (S47)

Explains the function and location of flame rollout safety switches.

6. Primary Limit Control (S10)

Details the primary limit control's function and automatic reset.

II-PLACEMENT AND INSTALLATION

Venting Practices

General Guidelines for Vent Terminations

Covers vent termination requirements, clearances, and material considerations.

VENT TERMINATION CLEARANCES FOR NON-DIRECT VENT INSTALLATIONS IN THE US AND CANADA

VENT TERMINATION CLEARANCES FOR DIRECT VENT INSTALLATIONS IN THE US AND CANADA

Details of Exhaust Piping Terminations for Direct Vent Installations

Details of Exhaust Piping Terminations for Non-Direct Vent Applications

Condensate Piping

CONDENSATE TRAP AND PLUG LOCATIONS

Shows locations for condensate trap and plug connections on the unit.

III-START-UP

B- Heating Start-Up

Procedure for initiating heating operation, including gas valve and burner ignition.

Failure To Operate

Troubleshooting steps for common issues when the unit fails to operate.

IV-HEATING SYSTEM SERVICE CHECKS

B- Gas Piping

Guidance on gas piping requirements, connectors, and pressure drop.

G- Proper Combustion

Checking combustion quality using CO2 levels and ensuring correct gas flow.

C- Testing Gas Piping

E- Check Manifold Pressure

Steps to measure and verify manifold gas pressure for proper combustion.

I- Proper Ground and Voltage

VI- MAINTENANCE

Cleaning Heat Exchanger

VII- Wiring and Sequence of Operation

Cooling

Single Stage Cooling

Two-Stage Cooling

Lennox ML296UH045XV36B Specifications

General

Brand	Lennox
Model	ML296UH045XV36B
Category	Furnace
Language	English