Table of Contents
Advertisement
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.
IMPORTANT
Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and
dangerous operation. Verify proper operation after
servicing.
IMPORTANT
The inner blower access panel and vent pipe 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.
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 filters and change if necessary
(monthly).
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-
sary . The blower motors are prelubricated for extended
bearing life. No further lubrication is needed.
7- Inspect the combustion air inducer and clean if neces-
sary.
8- 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.
9- 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 prop-
erly sized, open and unobstructed to provide combus-
tion air.
10- Inspect the furnace venting system to make sure it is
in place, structurally sound, and without holes, corro-
sion, 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 Na-
tional Fuel Gas Code
11- Inspect the furnace return air duct connection to en-
sure the duct is sealed to the furnace. Check for air
leaks on supply and return ducts and seal where nec-
essary.
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 com-
bustion 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 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 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 ad-
justing gas pressure. Not all gas valves are adjustable.
Verify correct temperature rise.
Page 26
Advertisement
Table of Contents
