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©
2021 Lennox Industries Inc.
Corp. 1601-L8
SL280UHNV
Service Literature
Revised 02/2021
COMMUNICATING-ENABLED SL280UHNV SERIES UNITS
SL280UHNV series units are 80% efficiency gas furnaces
used for upflow or horizontal applications only, manufac
tured with Lennox Duralok
t
heat exchangers formed of
aluminized steel. SL280UHNV units are available in heat
ing capacities of 40,000 to 100,000 Btuh and cooling ap
plications up to 5 tons. Refer to Engineering Handbook for
proper sizing.
SL280UHNV model units are equipped with a communicat
ing enabled SureLight
®
two-stage variable speed integrated
control. SL280UHNV unit meets the California Nitrogen Ox
ides (NO
x
) Standards and California Seasonal Efficiency re
quirements. All units use a redundant gas valve to assure
safety shut-off as required by C.S.A.
All specifications in this manual are subject to change. Pro
cedures outlined in this manual are presented as a recom
mendation only and do not supersede or replace local or
state codes. In the absence of local or state codes, the
guidelines and procedures outlined in this manual (except
where noted) are recommendations only and do not consti
tute code.
TABLE OF CONTENTS
I Unit Components
4
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Blower Data
16
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
II Installation
30
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
III Start Up
31
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
IV Heating System Service Checks
31
. . . . . . . . . . . . . .
V Typical Operating Characteristics
36
. . . . . . . . . . . . . .
VI Maintenance
37
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VII Wiring and Sequence of Operation
40
. . . . . . . . . . .
VIII Field Wiring and Jumper Settings
44
. . . . . . . . . . . .
IX Program Unit Capacity Size Mode
48
. . . . . . . . . . . .
X Troubleshooting
49
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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, contact with
sharp sheet metal edges can result in personal in
jury. Take care while handling this equipment and
wear gloves and protective clothing.
