Service - Lennox EL180UHN Installation Instructions Manual

Service

WARNING
ELECTRICAL SHOCK, FIRE,
OR EXPLOSION HAZARD.
Failure to follow safety warnings exactly could result in
dangerous operation, serious injury, death or property
damage.
Improper servicing could result in dangerous operation,
serious injury, death, or property damage.
Before servicing, disconnect all electrical power to
furnace.
When servicing controls, label all wires prior to
disconnecting. Take care to reconnect wires correctly.
Verify proper operation after servicing.
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.
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:
NOTE - Burner inspection and service is not recommend-
ed for annual furnace maintenance.
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
necessary.
5- Inspect the combustion air inducer and clean if
necessary.
6- 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. See "Induced-draft Furnace Heat
Exchanger Inspection Procedure".
7- Ensure sufficient 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.
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 obstructions and must slope upward away
from the furnace . 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
furnace inspection to ensure proper combustion
and operation. 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 disconnecting the indoor blower. For additional
details, please see Service and Application Note
H049.
2 - Verify that system total static pressure and airflow
settings 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. If manifold
pressure adjustment is necessary, consult the
Service Literature for unit specific information
on adjusting gas pressure. Not all gas valves are
adjustable. Verify correct temperature rise.
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