Maintenance - Lennox SL280UHNV Series Unit Information

VI-MAINTENANCE
Annual Furnace Maintenance
At the beginning of each heating season, and to comply
with the Lennox Limited Warranty, your system should be
checked by a licensed professional technician (or equiva­
lent) as follows:
WARNING
Disconnect power before servicing unit.
CAUTION
Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and dan­
gerous operation. Verify proper operation after ser­
vicing.
1- Check wiring for loose connections, voltage at indoor
unit and amperage of indoor motor
2- Check the condition of the belt and shaft bearings if ap­
plicable.
3- Inspect all gas pipe and connections for leaks
4- Check the cleanliness of filters and change if necessary
(monthly).
IMPORTANT
If a high­efficiency filter is being installed as part of
this system to ensure better indoor air quality, the fil­
ter must be properly sized. High­efficiency filters
have a higher static pressure drop than standard­ef­
ficiency glass/foam filters. If the pressure drop is too
great, system capacity and performance may be re­
duced. The pressure drop may also cause the limit to
trip more frequently during the winter and the indoor
coil to freeze in the summer, resulting in an increase
in the number of service calls.
Before using any filter with this system, check the
specifications provided by the filter manufacturer
against the data given in the appropriate Lennox
Product Specifications bulletin. Additional informa­
tion is provided in Service and Application Note
ACC­00­2 (August 2000).
WARNING
The blower access panel must be securely in place
when the blower and burners are operating. Gas
fumes, which could contain carbon monoxide, can
be drawn into living space resulting in personal inju­
ry or death.
5- Check the condition and cleanliness of burners and
heat exchanger and clean if necessary.
6- Check the cleanliness of blower assembly and clean
the housing, blower wheel and blower motor if neces­
7- Inspect the combustion air inducer and clean if neces­
8- Evaluate the heat exchanger integrity by inspecting the
9- Ensure sufficient combustion air is available to the fur­
10 Inspect the furnace venting system to make sure it is in
.
.
11 Inspect the furnace return air duct connection to ensure
12 Check the condition of the furnace cabinet insulation
13 Perform a complete combustion analysis during the fur­
14 Verify operation of CO detectors and replace batteries
Perform a general system test. Turn on the furnace to
check operating functions such as the start-up and shut-off
operation.
Page 37
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sary The blower motors are prelubricated for extended
bearing life. No further lubrication is needed.
sary.
heat exchanger per the AHRI heat exchanger inspec­
tion procedure. This procedure can be viewed at
www.ahrinet.org
nace. Fresh air grilles and louvers (on the unit and in the
room where the furnace is installed) must be properly
sized, open and unobstructed to provide combustion
.
air
place, structurally sound, and without holes, corrosion,
or blockage. Vent system must be free and clear of ob­
structions and must slope upward away from the fur­
.
nace Vent system should be installed per the National
Fuel Gas Code
the duct is sealed to the furnace. Check for air leaks on
supply and return ducts and seal where necessary
and repair if necessary.
nace inspection to ensure proper combustion and oper­
ation. Consult Service Literature for proper combustion
values.
as required.
1 - Check the operation of the ignition system, inspect
and clean flame sensor. Check microamps before and
after. Check controls and safety devices (gas valve,
flame sensor, temperature limits). Consult Service
Manual for proper operating range. Thermal Limits
should be checked by restricting airflow and not dis­
connecting the indoor blower. For additional details,
please see Service and Application Note H­04­9.
2 - Verify that system total static pressure and airflow set­
tings are within specific operating parameters.
3 - Clock gas meter to ensure that the unit is operating at
the specified firing rate. Check the supply pressure
and the manifold pressure. On two-stage gas furnaces
check the manifold pressure on high fire and low fire. If
manifold pressure adjustment is necessary, consult
the Service Literature for unit specific information on
adjusting gas pressure. Not all gas valves are ad­
justable. Verify correct temperature rise.
.