Repeat Cleaning; Reassembly Of The Burner Modules - Watts AERCO EXT Installation, Operation & Maintenance Manual

Modulex EXT Commercial Series
CHAPTER 8: Maintenance Schedule
2. Let stand for 10 to 20 minutes to allow the product to react. WARNING: do not let this
solution sit for more than 20 minutes, as over-exposure could damage the heat
exchanger.
3. Use a plastic bristle brush to clean the elements that can be reached, and then rinse all
surfaces with clean water.
4. Next, spray undiluted AXI-Therm Boiler Combustion Side Cleaner, Part B directly onto
all heat exchanger surfaces, allow to stand for 10 to 20 minutes, and then rinse with plenty
of clean water. This step creates a thin oxide layer on the aluminum pins, which protects
them during operation. WARNING: do not let this solution sit for more than 20 minutes,
as over-exposure could damage the heat exchanger.
5. Collect and dispose of the used solution and rinse water according to local regulations –
DO NOT dispose of rinse water into the environment or local sewer system.

8.12.3 Repeat Cleaning

The procedure in the previous section will remove smaller deposits and loosen larger deposits.
If there are still large deposits, repeat the manual cleaning process in section 8.12.1. At this
point a stiff plastic bristle brush should remove a significant amount of buildup.
If large deposits still remain, repeat the chemical cleaning process in section 8.12.2. After
cleaning with AXI-Therm, deposits will be loosened. The expansion and contraction of the heat
exchanger during normal operation will continue to shed debris.

8.13 Reassembly Of the Burner Modules

Follow the instructions to reassemble the burner modules:
1. After the cleaning of the combustion chamber and/or the burners, inspect the condensate
drain pipe to determine if it is free of obstructions; wash water should drain freely from the
condensate drain pipe. Also make sure the condensate siphon is free of obstructions,
cleaning it if necessary.
2. Reposition the burners into their proper positions.
3. Position the new gaskets onto each burner module and ensure proper positioning. Make sure
all surfaces are smooth and free of debris.
W A R N I N G !
The burner gaskets MUST be replaced at every cleaning.
4. Proceed with reassembly, performing whichever disassembly operation was chosen (all or
individual method) in reverse order.
a) Lower burner assembly
b) Reinstall gas collector tubes to the gas manifold tube.
c) Reinstall nuts "A," "C" and "B" screws to secure burner assembly to boiler body.
NOTE: Tighten the burner bolts with a torque of 9.5 ft-lbs (13 Nm).
d) Reassemble rubber hoses to the air intake manifold, place manifold onto the blowers,
then reattach tension spring clip to left and right ends of manifold.
e) Proceed to section 8.14 for final procedures before returning boiler to service.
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