Lennox LCH036 Installation Instructions Manual page 142

Blower shaft bearings are prelubricated. For extended
bearing life, relubricate at least once every two years with
a lithium base grease, such as Alvania 3 (Shell Oil),
Chevron BRB2 (Standard Oil) or Regal AFB2 (Texas Oil).
Use a hand grease gun for relubrication. Add only enough
grease to purge through the bearings so that a bead of
grease appears at the seal lip contacts.
C-Burners (Gas Units)
Periodically examine
appearance during the heating season. Before each
heating season examine the burners for any deposits or
blockage which may have occurred.
Clean burners as follows:
1- Turn off both electrical power and gas supply to unit.
2- Open burner compartment access panel.
3- Remove two screws securing burners to burner
support and lift the burners from the orifices. See
figure 39. Clean as necessary.
BURNER BOX ASSEMBLY
GAS VALVE
BURNERS
GAS MANIFOLD
FIGURE 39
4- Locate the ignitor under the left burners. Check
ignitor spark gap with appropriately sized twist drills
or feeler gauges. See figure 40.
5- Check the alignment of the ignitor and the sensor as
shown in figure 41 and table 18.
6- Replace burners and screws securing burner.
WARNING
Danger of explosion. Can cause injury or
death. Do not overtighten main burner
mounting screws. Snug tighten only.
burner flames for
FLAME
SENSOR
proper
Dimension
A
B
C
7- Replace access panel.
8- Restore electrical power and gas supply. Follow
lighting instructions attached to unit and use
inspection port in access panel to check flame.
D-Combustion Air Inducer (Gas Units)
A combustion air blower proving switch checks
combustion air inducer operation before allowing power
to the gas controller. Gas controller will not operate if
inducer is obstructed.
Under normal operating conditions, the combustion air
inducer wheel should be checked and cleaned prior to the
heating season. However, it should be examined
periodically during the heating season to establish an
ideal cleaning
disconnected, the condition of the inducer wheel can be
determined by looking through the vent opening.
Clean combustion air inducer as follows:
1- Shut off power supply and gas to unit.
2- Disconnect
combustion air inducer port.
3- Remove and retain screws securing combustion air
inducer to flue box. Remove and retain two screws from
bracket supporting vent connector. See figure 42.
4- Clean inducer wheel blades with a small brush and
wipe off any dust from housing. Clean accumulated
dust from front of flue box cover.
Page 42
IGNITOR
SPARK GAP
SHOULD BE
1/8" (3mm)
FIGURE 40
TABLE 18
Length - in. (mm)
Unit
Btuh Input
Ignitor
260K 7-3/4 (197)
360K 5 (127)
480K 2-1/4 (57)
schedule. With
pressure switch
Sensor
11 (279)
5-1/2 (140)
2-3/4 (70)
power supply
air tubing from