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C-Burners (Gas Units)
Periodically examine burner flames for proper
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- Remove burner compartment access panel.
3- Remove screws securing burner assembly to burner
support and remove assembly. See figure 34. Clean
as necessary.
4- Locate the ignitor under the left burners. Check
ignitor spark gap with appropriately sized twist drills
or feeler gauges. See figure 35.
BURNER BOX AS
SEMBLY
240KBTUH SHOWN
FIGURE 34
GAS
MANIFOLD
GAS
VALV
E
BURNER ASSEMBLY
SECURED WITH
MULTIPLE SCREWS
FIGURE 35
IGNITOR
SPARK GAP
SHOULD BE 1/8”
(3mm)
5- Check the alignment of the ignitor and the sensor as
shown in figure 36 and table 28.
6- Replace burners and screws securing burner.
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.
TABLE 28
Dimension
Unit
Btuh Input
Length - in. (mm)
Ignitor
Sensor
A
130K
7-3/4 (197)
11 (279)
B
180K
5 (127)
5-1/2 (140)
C
240K
2-1/4 (57)
2-3/4 (70)
D-Combustion Air Inducer (Gas Units)
A combustion air proving switch checks combustion air
inducer operation before allowing power to the gas
controller. Gas controller will not operate if inducer is
obstructed.
WARNING
Danger of explosion. Can cause injury
or death. Do not overtighten main
burner mounting screws. Snug tighten
only.
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 schedule. With power supply
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 pressure switch air tubing from
combustion air inducer port.
3- Remove and retain screws securing combustion air
inducer to flue box. Remove vent connector. See
figure 37.
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.
5- Return combustion air inducer motor and vent
connector to original location and secure with
retained screws. It is recommended that the
combustion air inducer gasket be replaced during
reassembly.
6- Clean combustion air inlet louvers on heat access
panel using a small brush.
