Page 1
10/09
*2P1009*
505,255M
*P505255M*
E
2006 Lennox Industries Inc.
Dallas, Texas, USA
THIS MANUAL MUST BE LEFT WITH THE
HOMEOWNER FOR FUTURE REFERENCE
INSTALLATION
INSTRUCTIONS
G50DF(X) Series
GAS FURNACE
505,255M
10/2009
Supersedes 05/2009
Table of Contents
G50DF(X) Unit Dimensions
2
. . . . . . . . . . . . . . . . . . . . . . .
G50DF(X) Parts Arrangement
3
. . . . . . . . . . . . . . . . . . . . .
G50DF(X) Gas Furnace
4
. . . . . . . . . . . . . . . . . . . . . . . . . .
Shipping and Packing List
4
. . . . . . . . . . . . . . . . . . . . . . . .
Safety Information
4
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General
5
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Use of Furnace as a Construction Heater
5
. . . . . . . . . . .
Combustion, Dilution, & Ventilation Air
6
. . . . . . . . . . . . .
Downflow Installation
9
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Setting Equipment
10
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filters
11
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Duct System
11
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Venting
11
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gas Piping
19
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrical
20
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unit Start−Up
24
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gas Pressure Adjustment
25
. . . . . . . . . . . . . . . . . . . . . . .
High Altitude Information
26
. . . . . . . . . . . . . . . . . . . . . . . .
Other Unit Adjustments
26
. . . . . . . . . . . . . . . . . . . . . . . . . .
Blower Performance
27
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Service
28
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Repair Parts List
30
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Planned Service
30
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SureLight
®
Integrated Control Diagnostic Codes
31
. . . .
SureLight
®
Control Troubleshooting
32
. . . . . . . . . . . . . . .
G50DF(X) Start−Up & Performance Check List
35
. . . . . .
WHAT TO DO IF YOU SMELL GAS:
Do not store or use gasoline or other
flammable vapors and liquids in the
vicinity of this or any other ap-
pliance.
Installation and service must be
performed by a qualified installer,
service agency or the gas supplier.
D
Do not try to light any appliance.
D
Do not touch any electrical switch; do not
use any phone in your building.
D
Immediately call your gas supplier from a
neighbor’s phone. Follow the gas supplier’s
instructions.
D
If you cannot reach your gas supplier, call
the fire department.
FIRE OR EXPLOSION HAZARD.
Failure to follow safety warnings exact-
ly could result in serious injury, death,
or property damage.
WARNING
D
Leave the building immediately.
Litho U.S.A.
