Vi-Maintenance - Lennox SL280UHNV Series Manual

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
dangerous operation. Verify proper operation after
servicing.
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 applicable.
3 - Inspect all gas pipe and connections for leaks.
4 - Check the cleanliness of fi lters and change if
necessary (monthly).
IMPORTANT
If a higheffi ciency fi lter is being installed as part of this
system to ensure better indoor air quality, the fi lter must
be properly sized. Higheffi ciency fi lters have a higher
static pressure drop than standardeffi ciency glass/foam
fi lters. If the pressure drop is too great, system capacity
and performance may be reduced. 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 fi lter with this system, check the
specifi cations provided by the fi lter manufacturer
against the data given in the appropriate Lennox
Product Specifi cations bulletin. Additional information 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 injury 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 necessary. The blower motors are prelubricated
for extended bearing life. No further lubrication is
needed.
7 - Inspect the combustion air inducer and clean if
necessary.
8 - Evaluate the heat exchanger integrity by inspecting
the heat exchanger per the AHRI heat exchanger
inspection procedure. This procedure can be
viewed at www.ahrinet.org
9 - Ensure suffi cient combustion air is available to the
furnace. 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.
10 - Inspect the furnace venting system to make sure
it is in place, structurally sound, and without holes,
corrosion, or blockage. Vent system must be free
and clear of obstructions and must slope upward
away from the furnace. Vent system should be
installed per the National Fuel Gas Code
11 - Inspect the furnace return air duct connection to
ensure the duct is sealed to the furnace. Check for
air leaks on supply and return ducts and seal where
necessary.
12 - Check the condition of the furnace cabinet insulation
and repair if necessary.
13 - Perform a complete combustion analysis during the
furnace inspection to ensure proper combustion
and operation. Consult Service Literature for proper
combustion values.
14 - Verify operation of CO detectors and replace
batteries as required.
Perform a general system test. Turn on the furnace to
check operating functions such as the start-up and shut-
off operation.
1 - Check the operation of the ignition system, inspect
and clean fl ame sensor. Check microamps before
and after. Check controls and safety devices (gas
valve, fl ame sensor, temperature limits). Consult
Service Manual for proper operating range. Thermal
Limits should be checked by restricting airfl ow and
not disconnecting the indoor blower. For additional
details, please see Service and Application Note
H049.
2 - Verify that system total static pressure and airfl ow
settings are within specifi c operating parameters.
3 - Clock gas meter to ensure that the unit is operating
at the specifi ed fi ring rate. Check the supply
pressure and the manifold pressure. On two-stage
gas furnaces check the manifold pressure on high
fi re and low fi re. If manifold pressure adjustment is
necessary, consult the Service Literature for unit
specifi c information on adjusting gas pressure.
Not all gas valves are adjustable. Verify correct
temperature rise.
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