Modulex Light Commercial Series
CHAPTER 9: Spare Parts Drawings and Lists
OMM-0158_A
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Cleaning the Heat Exchanger with Cleaning Solution
If mechanical cleaning has not removed all build-up, complete the instructions below to clean
the heat exchangers with a cleaning solution specifically designed for removing combustion by-
products from aluminum heat exchangers. The product approved by AERCO is
AXI-Therm
Boiler Combustion Side Cleaner
,
Part A
and
Part B
. The instructions below require 4 to 12
oz. (120 mL to 360 mL)
EACH
of Part A and Part B per 100,000 BTU/hr. of unit capacity.
C A U T I O N !
Use of neoprene gloves and protective goggles is recommended. Consult the Axiom Industries
web site (axiomind.com) for additional health and safety information.
1. Spray undiluted AXI-Therm Boiler Combustion Side Cleaner, Part A directly onto all the
heat ex
changer’s internal surfaces, continuing till they are completely wet. A heavy
application of the solution should reach most of the surfaces that cannot be seen.
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.
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.
