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E - BURNERS
Inspect the burners and burner flame at the beginning of
each heating season. If necessary, clean the burners as
indicated below:
1 - Turn off the electrical and gas supply to the furnace.
2 - Remove the burner box top.
3 - Remove the burner retaining bracket.
4 - Remove the burners.
5 - Clean the inside of each burner with a bottle brush as
shown in figure 26.
Cleaning Burners
BOTTLE
BRUSH
BURNER
FIGURE 26
6 - Replace the burners and the burner retaining brackĆ
et. Make sure the burners are properly seated in the
slots of the tray. The burner and manifold orifice must
be aligned.
7 - Check the electrode gap using appropriately sized
twist drills or feeler gauges. The gap should be beĆ
tween 2.79 and 3.56 mm (0.110 and 0.140 inches).
8 - Reinstall the burner box top.
CAUTION
Some soaps used for leak detection are corrosive
to certain metals. Carefully rinse piping thoroughly
after leak test has been completed. Do not use
matches, candles, flame or other sources of igniĆ
tion to check for gas leaks.
9 - Restore electrical power and gas supply to the furĆ
nace. Follow lighting instructions on the front of the
unit. Check the appearance of the burner flame, burnĆ
er pressure, gas flow, and temperature rise. If necesĆ
sary, make adjustments. See the other unit adjustĆ
ments section.
HEAT EXCHANGER
Periodically inspect the heat exchanger tubes and flue box
for corrosion. If necessary, clean as indicated below:
1 - Turn off the electrical and gas supply to furnace.
2 - Disconnect wiring to combustion air blower.
3 - Remove the screws securing the flue box to the furĆ
nace. Clean the flue box with a wire brush (brassĆbristle
brush recommended), and rags or a shop vacuum
cleaner.
4 - Disconnect the gas supply piping and the ignitor and
sensor wires. Remove the burner assembly from the
furnace.
5 - Since the heat exchanger tubes are crimped in severĆ
al locations, a thorough cleaning of the entire length of
each tube is not possible. However, remove any soot
deposits which are accessible with a wire brush (brassĆ
bristle brush recommended), and rags or a shop vacuĆ
um cleaner.
6 - Reinstall the flue box using a new gasket.
7 - Reconnect combustion air blower wiring.
8 - Reinstall the burner box, ignitor and sensor wires
and the gas supply piping.
9 - Carefully check all piping connections (factory and field)
for gas leaks. Use a leak detecting solution or other preĆ
ferred means.
IMPORTANT
Some soaps used for leak detection are corrosive to
certain metals. Carefully rinse piping thoroughly afĆ
ter leak test has been completed. Do not use
matches, candles, flame or other sources of ignition
to check for gas leaks.
10 Restore electrical power and gas supply. Follow
lighting instructions on front of unit. Check burner
flame and adjust if necessary.
