# 45466K003
Page 1
INSTALLATION INSTRUCTIONS
G1D91BU, G1D93BC, G1D93BU, CG90CB, & CG90UB
High Efficiency 90+ Condensing Gas Furnace
Manufactured By
A.A.C.
A Lennox International Company
421 Monroe Street
Bellevue, OH 44811
The installation of the furnace, wiring, warm air ducts, venting, etc. must conform to the requirements of the
National Fire Protection Association; the National Fuel Gas Code, ANSI Z223.1/NFPA No. 54 (latest edition)
and the National Electrical Code, ANSI/NFPA No. 70 (latest edition) in the United States; CSA B149.1
(latest edition) Natural Gas and Propane Installation Codes and the Canadian Electrical Code Part 1, CSA
22.1 (latest edition) in Canada; and any state or provincial laws, local ordinances (including plumbing or
wastewater codes), or local gas utility requirements. Local authorities having jurisdiction should be con-
sulted before installation is made. Such applicable regulations or requirements take precedence over the
general instructions in this manual.
IMPORTANT
Do not store combustible materials, including
gasoline and other flammable vapors and
liquids, near the furnace, vent pipe, or warm
air ducts. The homeowner should be cau-
tioned that the furnace area must not be
used as a broom closet or for any other
storage purposes. Such uses may result in
actions that could cause property damage,
personal injury, or death.
WARNING
This furnace is not approved for installation in
a mobile home. Do not install this furnace in a
mobile home. Installation in a mobile home
could result in actions that could cause prop-
erty damage, personal injury, or death.
WARNING
Improper installation, adjustment, alteration, service, or maintenance can cause
injury or property damage. Refer to this manual. For assistance or additional informa-
tion, consult a qualified installer, service agency, or the gas supplier.
WARNING
TABLE OF CONTENTS
SAFETY ................................................. 2
INSTALLATION....................................... 3
START-UP ............................................ 19
OPERATION ........................................ 20
MAINTENANCE ................................... 23
REPAIR PARTS .................................... 24
CONTROL SYSTEM DIAGNOSTICS .. 25
WIRING DIAGRAMS ............................ 26
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