Lennox SL280UHNV User's Information Manual

USER’S INFORMATION

©2017 Lennox Industries Inc.

Dallas, Texas, USA

507650-01
10/2017

MANUAL

SL280UHNV
SERIES

WARNING

Improper installation, adjustment, alteration, service
or maintenance can cause property damage, personal
injury or loss of life. Installation and service must be
performed by a licensed professional HVAC installer or
equivalent, service agency, or the gas supplier.

WARNING

FIRE OR EXPLOSION HAZARD.

Failure to follow safety warnings exactly
could result in serious injury, death, or
property damage.

Do not store or use gasoline or other ammable

vapors and liquids in the vicinity of this or any
other appliance.

Installation and service must be performed

by a qualied installer, service agency or the

gas supplier.

WHAT TO DO IF YOU SMELL GAS:

• Do not try to light any appliance.

• Do not touch any electrical switch; do not

• use any phone in your building.

• Immediately call your gas supplier from a

• neighbor’s phone. Follow the gas supplier’s

• instructions.

• If you cannot reach your gas supplier, call

• the re department.

SL280UHNV Parts Identication

Combustion Air
Inducer

Gas Valve

Combustion Air Inducer
Pressure Switch

Heat Exchanger
Assembly

Blower Motor

FIGURE 1

NOTE - This manual is the property of the homeowner

and must be left with the equipment user.

Notice to Homeowner

This furnace is equipped with safety devices that protect
you and your property. If one or more of these devices is
activated, furnace operation will stop. If your home is left
unattended for an extended period of time, equipment op­eration must be checked periodically.

Ignition Control

If this is not possible, the water supply to the house should
be shut off and the pipes should be drained. This will pre­vent problems associated with a NO HEAT condition (fro­zen pipes, etc.)

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CAUTION

Before attempting to perform any service or maintenance,
turn the electrical power to unit OFF at the disconnect
switch.

Your furnace is a gas appliance. It is critical that the gas
supplied to the unit be completely burned to avoid the pro­duction of carbon monoxide gas. Complete combustion of
the gas requires, but is not limited to, correct gas pressure

and gas ow rate, adequate combustion air and proper

venting.

NOTICE

Any additions, changes, or conversions required in order
for the appliance to satisfactorily meet the application
needs must be made by a licensed professional installer

(or equivalent) using factory-specied and approved

parts.

Safety Instructions

1 - Keep the furnace area clear and free of combustible

material, gasoline, and other ammable vapors

and liquids. If it is installed in an insulated area, the
furnace must be kept free of insulating material.
Insulating material may be combustible.

2 - DO NOT obstruct air ow to unit. Unit must receive

an unobstructed ow of combustion and ventilating

air. DO NOT block or obstruct air openings on
the furnace or air openings to the area in which
the furnace is installed. Take care to maintain
established clearances surrounding the furnace.

3 - DO NOT store chlorine or uorine products near

unit or introduce these products into the combustion
air. These products can cause furnace corrosion.

4 - DO NOT draw return air from a room where this

furnace, or any other gas appliance (ie., a water
heater), is installed. When return air is drawn from

a room, a negative pressure is created in the room. If
a gas appliance is operating in a room with negative

pressure, the ue products can be pulled back down
the vent pipe and into the room. This reverse ow
of the ue gas may result in incomplete combustion

and the formation of carbon monoxide gas. This
toxic gas might then be distributed throughout the
house by the furnace duct system.

WARNING

The blower door must be securely in place when the
blower and burners are operating. Gas fumes, which
could contain carbon monoxide, can be drawn into the
living space resulting in personal injury or death.

WARNING

Asphyxiation Hazard
The exhaust vent for this furnace must be leak-free and

must be securely connected to the furnace ue collar at

all times.

For your safety and to fulll the terms of the limited

warranty, a licensed professional service technician (or
equivalent) must annually inspect this furnace and its
vent system.

Exposure to carbon monoxide gas can cause personal
injury and even death to all occupants, including pets.
Any item that is powered by, or gives off heat from, a
combustion process (including lawn mowers, automo-

biles, and replaces) has the potential to produce carbon

monoxide gas. Because of this, Lennox recommends
the use of a carbon monoxide detector in your home,
even if you do not own gas appliances. Reliable de-

tectors are available at reasonable retail prices. Contact
your Lennox dealer for more details about this invest­ment in your safety.

Your furnace is designed to meet standards set by nation­al agencies, and to operate safely when properly installed
and maintained. However, the unit’s performance can be
greatly impacted by the individual installation and the op­erating environment. It is your responsibility to ensure that
this appliance is maintained.

Proper maintenance is critical for your safety and the sat­isfactory operation m./of the product. Lennox strongly
recommends annual inspection and maintenance of this
appliance. Contact your Lennox dealer for an inspection
by a licensed professional service technician.

Start-Up & Operation

NOTE - When the furnace begins heating mode, the di­agnostic LED on the furnace control will display “H1” for
heating operation in 1st stage, or “H2” for heating opera­tion in 2nd stage. The LED can be seen through the view-

port on the lower access panel. See gure 2.

WARNING

If you do not follow these instructions exactly, a re or

explosion may result causing property damage, personal
injury or death.

BEFORE LIGHTING smell all around the appliance area

for gas. Be sure to smell next to the oor because some
gas is heavier than air and will settle on the oor.

The gas valve on the SL280UHV is equipped with a gas
control switch. Use only your hand to move the gas con­trol switch. Never use tools. If the switch will not move by
hand, do not try to repair it. Call a licensed professional
service technician (or equivalent). Force or attempted re-

pair may result in a re or explosion.

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