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Page 33 of 39
Issue 1132
Cleaning the Heat Exchanger and Burners
NOTE:
Use papers or protective covering in front of the
furnace during cleaning.
1. Turn off both electrical and gas power supplies to
furnace.
2. Remove flue pipe and top cap
(some applications top
cap can remain)
from the unit.
3. Label the wires from gas valve, rollout switches, primary
limit switch and make-up box then disconnect them.
4. Remove the screws that secure the combustion air
inducer/pressure switch assembly to the collector box.
Carefully remove the combustion air inducer to avoid
damaging blower gasket. If gasket is damaged, it must
be replaced to prevent leakage.
5. Remove the collector box located behind the combustion
air inducer. Be careful with the collector box gasket. If
the gasket is damaged, it must be replaced to prevent
leakage.
6. Disconnect gas supply piping. Remove the screw
securing the burner box cover and remove cover.
Remove the four screws securing the burner manifold
assembly to the vestibule panel and remove the
assembly from the unit.
7. Remove screws securing burner box and remove burner
box.
8.
NOX units only
- Remove screw securing NOX insert.
Remove NOX insert. See Figure 30.
Figure 29
BURNER, COMBUSTION AIR INDUCER ASSEMBLY & HEAT EXCHANGER REMOVAL