7. Remove top partition.
8. Place field-fabricated cardboard on metal tray beneath collector box to prevent debris form entering blower compartment..
9. Remove flue collector box from secondary heat exchanger tube flnge. This exposes inside surfaces of secondary tubes of heat exchanger..
10. Clean secondary tubes and flue pipe with a stiff brush and vacuum cleaner..
11. Remove louvered door.
12. Disconnect limit control wires.
13. Disconnect oil line and remove oil burner from furnace.
14. Remove observation door and collar on observation tube..
15. Remove intermediate panel. Care must be taken not to bend or damage limit control..
CAUTION: Never use incendiary type cleaners (smoke sticks) for cleaning!
WARNING: For all heat exchanger plates that have been removed, the gaskets MUST be replaced. Failure to replace
gaskets could lead to heat exchanger leakage, sooting, and a hazardous condition which could lead to bodily harm.
16. Loosen to hand tightness the 3 nuts labeled “A” in Fig. 4. Remove screws labeled “B” in Fig. 4. Slide combustion chamber forward out
of heat exchanger. Be careful not to bump combustion chamber as it becomes brittle after having been fired..
17. Use a stiff brush and vacuum cleaner to clean inside of primary drum..
18. Before reassembly, heat exchanger and combustion chamber should be inspected to determine if replacement is required. After cleaning,
place combustion chamber back into primary drum and secure with “B” screws. Ensure that cover plate gasket is in place before tightening
screws. Care must be taken not to damage combustion chamber. The “B” screws should be tightened to 35–45 lb.in..
19. Tighten “A” nuts to 30 lb.-in. of torque (firm, but not overly tight).
20. Replace intermediate panel, observation tube collar, observation door, limit wiring, and oil burner.
21. Replace collector box on secondary tube flange, ensuring proper placement of gasket. Tighten screws to 35–45 lb.in. of torque.
22. Replace top partition, inside collar on flue pipe, top rear panel, outside flue collar, and blower door.
23. Reconnect flue pipe and oil line(s).
Fig. 3–Reinstalling Cleanout Port Covers
A96311
FLUE BOX
PARTITION
PANEL
CLEANOUT
PORT COVER
WING
CLAMP
NUT
CLEANOUT
COVER
GASKET
CLEANOUT
COVER
CLAMP
BRACKET
INSULATION
Fig. 4–Removing Combustion Chamber
A96398
A
B
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