Closed Loop Water Treatment

In a perfect world, a closed system would truly be closed, requiring no treatment and operating without concern of uncontrolled corrosion. Of course, this perfect world does not exist as closed systems typically lose enough water and leak enough air to require adequate corrosion protection.

AQUAGUARD 102 closed loop water treatment for both circulating hot water heating and chilled water systems containing water or glycol. AQUAGUARD 102 is a molybdate based treatment formulated with a unique blend of corrosion inhibitors, dispersants and pH buffers to provide excellent corrosion control, disperse previously deposited corrosion products and solids and maintain sufficient pH to prevent acidic corrosion.


  • Extremely effective and long lasting inhibitor for closed systems.
  • Concentrated for cost effective dilutions.
  • Formulated with a proprietary blend of corrosion inhibitors designed to protect all metallic components in the system including yellow metal valves, pipes and fittings.
  • Compatible with all closed glycol and water systems.
  • Chromate free formulation for improved environmental performance.
  • Does not contribute to microbial growth unlike nitrite, phosphate and phosphonate treatments.


AQUAGUARD 102 is recommended for any closed circulating hot water heating or chilled loop systems. It is compatible with both water and glycol. AQUAGUARD 102 may be used wherever a high performing inorganic inhibitor is desired.

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