Page 1
06/11
*2P0611*
506763−01
*P506763-01*
2011 Lennox Industries Inc.
Dallas, Texas, USA
UPFLOW
HORIZONTAL LEFT
HORIZONTAL RIGHT
AIR FLOW
AIR FLOW
AIR FLOW
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 installer (or
equivalent), service agency or the gas supplier.
INSTALLATION
INSTRUCTIONS
SL280UHV
DAVE LENNOX SIGNATURE
®
COLLECTION GAS FURNACE
UPFLOW / HORIZONTAL AIR DISCHARGE
506763−01
06/2011
Supersedes 03/2011
THIS MANUAL MUST BE LEFT WITH THE
HOMEOWNER FOR FUTURE REFERENCE
This 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.
CAUTION
As with any mechanical equipment, personal injury
can result from contact with sharp sheet metal
edges. Be careful when you handle this equipment.
NOTICE
A thermostat is not included and must be ordered
separately.
The Lennox icomfort Touch
®
thermostat must be
used in communicating applications.
In non−communicating applications, the Lennox
ComfortSense
®
7000 thermostat may be used, as
well as other non−communicating thermostats.
In all cases, setup is critical to ensure proper sys-
tem operation.
Field wiring for both communicating and non−com-
municating applications is illustrated in diagrams,
which begin on Page 27.
Table of Contents
Unit Dimensions
2
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts Arrangement
3
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SL280UHV Gas Furnace
4
. . . . . . . . . . . . . . . . . . . . . . . . .
Shipping and Packing List
4
. . . . . . . . . . . . . . . . . . . . . . . .
Safety Information
4
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Use of Furnace as a Construction Heater
5
. . . . . . . . . . .
General
5
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Combustion, Dilution & Ventilation Air
6
. . . . . . . . . . . . . .
Setting Equipment
9
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filters
12
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Duct System
12
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Venting
13
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gas Piping
23
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrical
25
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Integrated Control Settings
36
. . . . . . . . . . . . . . . . . . . . . . .
Blower Performance Data
39
. . . . . . . . . . . . . . . . . . . . . . . .
Unit Start−Up
51
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gas Pressure Adjustment
52
. . . . . . . . . . . . . . . . . . . . . . . .
Proper Combustion
52
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
High Altitude
53
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Other Unit Adjustments
54
. . . . . . . . . . . . . . . . . . . . . . . . . .
Heating Sequence of Operation
54
. . . . . . . . . . . . . . . . . . .
Service
56
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Planned Service
59
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Repair Parts List
59
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Integrated Control Diagnostic Codes
60
. . . . . . . . . . . . . . .
Program Unit Capacity/Size Mode
67
. . . . . . . . . . . . . . . . .
Troubleshooting
68
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Litho U.S.A.
