Page 1
2015 Lennox Industries Inc.
Dallas, Texas, USA
AIR FLOW
UPFLOW
AIR FLOW
AIR FLOW
HORIZONTAL RIGHT
HORIZONTAL LEFT
INSTALLATION
INSTRUCTIONS
ML180UH
MERIT
®
SERIES GAS FURNACE
UPFLOW / HORIZONTAL AIR DISCHARGE
507323-01
06/2015
Supersedes 507009-01
THIS MANUAL MUST BE LEFT WITH THE
HOMEOWNER FOR FUTURE REFERENCE
This is a safety alert symbol and should never be ignored.
When you see this symbol on labels or in manuals, be alert
to the potential for personal injury or death.
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, personal injury
can result from contact with sharp sheet metal
edges. Be careful when you handle this equipment.
Table of Contents
Unit Dimensions 2................................
ML180UH Gas Furnace 3..........................
Shipping and Packing List 3........................
Safety Information 3...............................
Use of Furnace as a Construction Heater 4...........
General 4........................................
Combustion, Dilution & Ventilation Air 5..............
Setting Equipment 8...............................
Filters 11..........................................
Duct System 12....................................
Venting 13........................................
Gas Piping 20.....................................
Electrical 22.......................................
Integrated Control 24...............................
Unit Start-Up 26...................................
Gas Pressure Adjustment 26........................
High Altitude 26....................................
Proper Combustion 26..............................
Other Unit Adjustments 28..........................
Twinning the ML180UH 29..........................
Service 30........................................
Repair Parts 32....................................
Litho U.S.A.
To Next Page
Need help?
General