WET USA Inc. (World Environmental Technologies)...Water and Wastewater Treatment for your facility.
Servicing the Water & Wastewater Industry since 1992

Product Bulletin
Closed Loop Treatment

Printable Version
Material Safety Data Sheet


WET-4305 Series is a multifunctional liquid closed system treatment.  It is a liquid blend of corrosion inhibitors, scale inhibitors, polymeric dispersants, copper corrosion inhibitors and a pH buffer to prevent scaling and corrosion from occurring in the closed system.  It functions as a protective film-forming corrosion inhibitor utilizing nitrite, borate, azole.  It helps keep systems clean free from corrosive attack and harmful insulating deposits, thereby maintaining design heat transfer efficiency and longer equipment life.

  • The “D” version includes a special dye for early detection of problems such as leaks and acidity.
  • The “E” version is formulated with Erythorbate to reduce ferric iron to ferrous iron.
  • The “S” version does not contribute hydroxide to the final water, where high pH is not acceptable.

• Protects most metals, including sweated copper lines, in chilled and hot water systems from corrosive attack
• Minimizes heat-absorbing sludge and mineral scale deposits in system
• Remains effective at temperatures of 300?F and above
• Compatible with glycol-based antifreezes
• Helps extend equipment life
• Reduces maintenance time and costs
• Superior corrosion inhibition due to synergy between nitrites and molybdate
• Does not affect non-metallic materials in cooling systems

WET-4305 Series is a scale & corrosion inhibitor designed for HVAC closed loop systems. It is also used in systems that contain antifreeze (either automotive or HVAC grade), to provide additional protection against corrosion. Most antifreeze formulations, especially the automotive grades, do not contain sufficient buffer and corrosion inhibitor for HVAC applications. The addition of WET-4305 Series will increase the buffer and inhibitor levels to provide a greater protection against corrosion.

1.0 fl. oz. per gal yields 250 ppm nitrite as NO2 . To assure a clean system that is free of both corrosion and scale deposits, the following dosages are recommended.

  • Chilled Water Systems: 1.5 fl. oz./gal
  • Hot Water Systems: 3.0 fl. oz./gal

Note: Dirty or contaminated systems should be drained, flushed, and chemically cleaned before treatment to get maximum results. A side Stream filter is highly recommended to ensure proper removal of loosened particles. A biocide program may also be necessary to remove any microbio contamination. Consult your WET representative for cleaning, filtration, and/or biocide recommendations.

WET-4305 Series is non-corrosive to ordinary metals used in feeding devices. Feed WET-4105 Series to system with any type of by-pass feeder or proportional pump.

For information concerning typical properties, health hazard, flammability, reactivity, handling & storage, please consult the MSDS.

Available in 55, 30, 15, 5 gal drums, bulk shipments, and returnable 200 and 400 gallon tote containers.

Our technical staff is available to assist in the application of WET’s products. You may request assistance through your sales representative or by contacting WET, Inc. at (877) 938-4621.

Improper application of this product will result in insufficient protection and/or potential damage to the system being treated. Please follow the recommendations of your WET representative.

The information and statements herein are believed to be reliable, but are not to be construed as warranty or representation for which we assume legal responsibility.

For Medical and Transportation Emergencies involving WET products call (24-hour response): (800)535-5053


Revision Date: November 2007

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