Steam Boiler Treatment

AQUAGUARD 420 is a concentrated multi-functional liquid steam boiler treatment designed to control corrosion, scale and sludge while maintaining alkalinity in the boiler.

AQUAGUARD 420 is a synergistic blend of corrosion and scale inhibitors, alkalinity boosters and dispersants. AQUAGUARD 420 is an excellent choice for systems with a high proportion of returned steam condensate and minimal requirements for additional feed water makeup.


  • All in one solution
  • Reduces downtime and maintenance by controlling scale and corrosion
  • Helps to maintain clean heat transfer surfaces, ensuring efficient boiler operation
  • Remains in the boiler and does not contain volatile materials that could cause steam contamination
  • Easy to use, test and control
  • Effective in hard or soft water areas


AQUAGUARD 420 is ideal for a variety of commercial, institutional and small industry systems. Where overhead or condensate/steam line corrosion control is required, AQUAGUARD 420 should be used in conjunction with one of our AQUAGUARD 200 series of products. AQUAGUARD 420 is not meant to be used in hot water boilers or any other type of heat exchange equipment other than steam boilers.

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