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VI-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:
NOTE -
Burner inspection and service is not recommended
for annual furnace maintenance.
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
Fire Hazard. Use of aluminum wire with this
product may result in a fire, causing property dam
age, severe injury or death. Use copper wire only
with this product.
CAUTION
Failure to use properly sized wiring and circuit
breaker may result in property damage. Size wiring
and circuit breaker(s) per Product Specifications
bulletin (EHB) and unit rating plate.
1- Check wiring for loose connections, voltage at indoor
unit and amperage of indoor motor
.
2- Inspect all gas pipe and connections for leaks
.
3- Check the cleanliness of filters and change if necessary
(monthly).
4- Check the cleanliness of blower assembly and clean
the housing, blower wheel and blower motor if neces
sary
.
5- Inspect the combustion air inducer and clean if neces
sary.
TABLE 13
Furnace
Cabinet Width
Filter Size
Side Return
Bottom Return
A - 14-1/2”
16 X 25 X 1 (1)
14 X 25 X 1 (1)
B - 17-1/2”
16 X 25 X 1 (1)
16 X 25 X 1 (1)
C - 21”
16 X 25 X 1 (1)
20 X 25 X 1 (1)
6- Evaluate the heat exchanger integrity by inspecting the
heat exchanger per the AHRI heat exchanger inspec
tion procedure. This procedure can be viewed at
www.ahrinet.org. See “Induced-draft Furnace Heat Ex
changer Inspection Procedure”.
7- Ensure sufficient combustion air is available to the fur
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
.
8- 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 ob
structions and must slope upward away from the fur
nace
.
Vent system should be installed per the National
Fuel Gas Code
9- 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
.
10- Check the condition of the furnace cabinet insulation
and repair if necessary.
11- Perform a complete combustion analysis during the fur
nace inspection to ensure proper combustion and oper
ation. Consult Service Literature for proper combustion
values.
12- Verify operation of smoke detectors and 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 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.
Not all gas valves are ad
justable
.
Verify correct temperature rise.
