Page 1
©
2017 Lennox Industries Inc.
ML180UHA
Service Literature
Corp. 1218-L4
Revised 05 /2017
ML180UHA series units are mid-efficiency gas furnaces
used for upflow or horizontal applications only, manufac
tured with Lennox Duralok Plus
t
heat exchangers formed
of aluminized steel. ML180UHA units are available in heat
ing capacities of 69.6 to 139.3 MJ/h and cooling applica
tions 10 to 17 kW. Refer to Engineering Handbook for prop
er sizing.
Units are factory equipped for use with natural gas. Kits are
available for conversion to LP/Propane operation.
ML180UHA model units are equipped with a hot surface
ignition system. All units use a redundant gas valve to as
sure safety shut-off as required.
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.
WARNING
This product contains a chemical known to the State
of California to cause cancer, birth defects, or other
reproductive harm.
TABLE OF CONTENTS
Specifications
Page 2
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Blower Data
Page 3
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts Identification
Page 5
. . . . . . . . . . . . . . . . . . . . . . . . .
I Unit Components
Page 6
. . . . . . . . . . . . . . . . . . . . . . . .
II Installation
Page 14
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
III Start Up
Page 14
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
IV Heating System Service Checks
Page 15
. . . . . . . . .
V Typical Operating Characteristics
Page 19
. . . . . . . . .
VI Maintenance
Page 20
. . . . . . . . . . . . . . . . . . . . . . . . . .
VII Wiring and Sequence of Operation
Page 22
. . . . . .
IMPORTANT
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 qualified installer, service agency
or the gas supplier.
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.
WARNING
Do not modify this appliance.