AERCO Modulex EXT 1530 - 3060 - Manual (Page 34)

MODULEX EXT 1530, 1912, 2295, 2677, 3060 Boilers
Installation, Operation & Maintenance Manual
3.15 Water Treatment
The chemical/physical composition of the heating system’s water is fundamental for the boiler’s
correct operation and safety.
Among the problems caused by poor quality of feed water, the most frequent and the most
serious is the buildup of deposits on boiler thermal exchange surfaces.
Less frequent, but also serious, are deposits on the water circulating piping surfaces. Because
of the low thermal conductivity of mineralization desposits caused by improperly treated water,
the thermal exchange efficiency may be seriously reduced, and can result in very dangerous
localized overheating.
AERCO suggests treating and conditioning feed water for the heating circuit in the following
cases:
• When the hardness of the water is higher than 9 grains (15°f).
• For cold/hot water installations with large water content.
• Renewal of the water system due to uncontrolled leakages.
• Subsequent refilling of the system due to maintenance work on the installation.
• Presence of different metals in the water circuit.
Properly treated system and feed water will eliminate or substantially reduce the following
problems:
• lime scale deposit
• corrosion sludge
• deposits
• microbiological growths (molds, bacteria etc.)
An appropriate treatment of the supply water will prevent the above stated problems and will
maintain the correct operation and efficiency of the boiler over time.
In order to properly treat water for use in a hydronic boiler heating system, the following
physical/chemical characteristics must be addressed.
Water Hardness: If water hardness is over 6 to 9 grains, a water softener must be used.
Sediment: If sediment is present in the system, a sediment filter or other appropriate device,
must be used.
Water pH: If water has a pH above 8, or below 5, then the water must be treated to provide a
medium pH of between 5 and 8.
The system water to be judged for water characteristics should be taken from the return pipe of
the primary circuit downstream of the circulating pump.
3.16 Important Installation Warnings
3.16.1 Oxygen Levels in the System Water Warning
All necessary precautions must be taken for preventing the formation and localization of
oxygen in the system’s water. For this reason, ensure that the plastic piping used in
under-floor heating systems is impermeable to oxygen.
3.16.2 Antifreeze Compatibility Warning
If any anti-freeze solutions are used ensure that they are compatible with aluminum and
any other boiler components and materials.
Page 34 of 138 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 OMM-0095_0E
12/01/14 Phone: 800-526-0288 GF-139