Lennox ML193UH110XE60C

Page 1
© 2019 Lennox Industries Inc.
Litho U.S.A.
Corp. 1905
ML193UHE
Service Literature
ML193UHE SERIES UNITS
ML193UHE series units are high-efficiency gas fur
naces manufactured with Lennox DuralokPlust alumi
nized steel clamshell-type heat exchangers, with a stainless
steel condensing coil. ML193UHE units are available in
heating input capacities of 30,000 to 110,000 Btuh (8.8 to
32.2 kW) and cooling applications from 2 through 5 tons (7.0
through 17.6 kW). Refer to Engineering Handbook for proper
sizing.
Units are factory equipped for use with natural gas. A kit is
available for conversion to LPG operation. All ML193UHE
units are equipped with a hot surface ignition system. The
gas valve is redundant to assure safety shut-off as re
quired by C.S.A.
The heat exchanger, burners and manifold assembly can be
removed for inspection and service. The maintenance section
gives a detailed description on how this is done.
The ML193UHE can be “twinned” with a second unit. See
twinning kit 16W72 for information for two units to operate
as one, in a shared duct system controlled by a single ther
mostat.
All specifications are subject to change. Procedures outlined
in this manual are presented as a recommendation only
and do not supersede or replace local or state codes.
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.
Table of Contents
Specifications 2.................................
Optional Accessories 4..........................
Blower Performance Data 5......................
I-Unit Components 7............................
II Placement and Installation 20....................
III-Start-Up 39...................................
IV-Heating System Service Checks 40..............
V-Typical Operating Conditions 44.................
VI-Maintenance 45...............................
VII-Sequence of Operation and Flow Charts 48......
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.

Lennox ML193UH110XE60C Specifications

General

Model	ML193UH110XE60C
Type	Gas Furnace
Efficiency Rating	93% AFUE
Heating Capacity	110, 000 BTU
Stages	Single-stage
Fuel Type	Natural Gas
Configuration	Upflow/Horizontal
BTU Input	110, 000 BTU
Blower Motor Type	ECM
Vent Type	Direct Vent
Warranty	Limited Lifetime Heat Exchanger Warranty, 5-Year Limited Parts Warranty

Summary

ML193 UHE SERIES UNITS

Safety Warnings

Warns about electric shock, improper installation, and handling hazards.

SPECIFICATIONS

Heating Performance

Details heating input, output, and temperature rise for different models.

BLOWER DATA

ML193 UH030 XE36 B Performance

Presents air volume and wattage data for the 030 model at various static pressures.

ML193 UH045 XE36 B Performance

Presents air volume and wattage data for the 045 model at various static pressures.

ML193 UH070 XE36 B Performance

Presents air volume and wattage data for the 070 model at various static pressures.

ML193 UH090 XE36 C Performance

Presents air volume and wattage data for the 090 model at various static pressures.

BLOWER DATA (Continued)

ML193 UH090 XE48 C Performance

Presents air volume and wattage data for the 090 model at various static pressures.

ML193 UH110 XE48 C Performance

Presents air volume and wattage data for the 110 model at various static pressures.

ML193 UH110 XE60 C Performance

Presents air volume and wattage data for the 110 model at various static pressures.

ML193 UHE PARTS IDENTIFICATION

Control Box Identification

Identifies the electrical control center housing various components.

Heat Exchanger Identification

Identifies the primary heat exchanger component.

I-UNIT COMPONENTS

Electrostatic Discharge (ESD) Precautions

Provides essential precautions to prevent damage from electrostatic discharge.

Control Box Components

Integrated Ignition Control (A92)

Explains the hot surface ignition system and its integrated control.

ELECTRONIC IGNITION SYSTEM

Electronic Ignition Sequence

B-HEATING COMPONENTS

Flame Rollout Switches

Details the function and operation of flame rollout safety switches.

Primary Limit Control

Explains the primary limit control and its role in sensing excess heat.

GAS VALVE AND FLAME SENSOR

Flame Sensor Function

AIR HANDLING COMPONENTS

Combustion Air Inducer and Header Box

Combustion Air Pressure Switch

Explains the function of the pressure switch in monitoring combustion airflow.

II-PLACEMENT AND INSTALLATION

Pipe and Fittings Specifications

JOINT CEMENTING PROCEDURE

PVC Glue Fume Hazard

Warns about the danger of explosion from PVC glue fumes during system checks.

GENERAL GUIDELINES FOR VENT TERMINATIONS

Vent Termination Clearances

VENT TERMINATION CLEARANCES FOR NON-DIRECT VENT INSTALLATIONS

VENT TERMINATION CLEARANCES FOR DIRECT VENT INSTALLATIONS

III-START-UP

Preliminary and Seasonal Checks

Heating Start-Up Procedure

Details the initial heating start-up procedure, including gas safety and ignition.

Failure To Operate Checklist

IV-HEATING SYSTEM SERVICE CHECKS

Gas Supply Pressure Measurement

Explains how to measure and check gas supply and manifold pressures.

E-PROPER COMBUSTION

Combustion Analysis Procedure

G- PROPER GROUND AND VOLTAGE

Grounding and Voltage Verification

Details procedures for checking furnace grounding and voltage to the integrated control.

VI-MAINTENANCE

CLEANING HEAT EXCHANGER

VII-WIRING DIAGRAM AND SEQUENCE OF OPERATION

Furnace Wiring Diagram

Provides a detailed wiring diagram of the furnace control system.

Heating Sequence of Operation

Explains the step-by-step process for the furnace's heating cycle.

TROUBLESHOOTING: HEATING SEQUENCE OF OPERATION

Normal Heating Mode Operations

Outlines the normal operational flow for heating.

Abnormal Heating Mode - Initial Checks

Describes abnormal conditions detected during initial checks like polarity and voltage.

Abnormal Heating Mode - Safety Switch Issues

TROUBLESHOOTING: HEATING SEQUENCE OF OPERATION (CONTINUED)

Ignitor and Flame Sensing Issues

Limit and Pressure Switch Faults

TROUBLESHOOTING: COOLING SEQUENCE OF OPERATION

Normal Cooling Mode Operations

Outlines the normal operational flow for cooling.

Abnormal Cooling Mode Faults