Written by IAPMO 10:01 am Code News, IAPMO News

IAPMO Publishes Standard for Quality of Heat Transfer Fluids Used in Hydronics Systems

The International Association of Plumbing and Mechanical Officials (IAPMO®) has published IAPMO/ANSI H1001.1 (Standard for Quality of Heat Transfer Fluids Used in Hydronics Systems) as an American National Standard.

IAPMO/ANSI H1001.1 provides minimum requirements for maintaining quality of liquid aqueous-based heat transfer fluids over the life of the system and optimizing the life of system components in both residential and non-residential closed hydronic heating and cooling applications. This standard is designed to be inclusive of hybrid renewable energy systems as a means of promoting more sustainable methods of energy consumption.

IAPMO/ANSI H1001.1 addresses both chemical and non-chemical treatment methods with focus on the importance of water treatment and corrosion prevention. Such provisions are accompanied by recommended hydronic water quality parameters for the following conditions:

  • Systems with chemical additives
  • High purity water systems
  • Hybrid hydronic and ground source heat pump systems

Additionally, this comprehensive document provides guidance for water treatment programs, appropriate cleaning and flushing methods, chemical handling and injection, and recommended system configurations supplemented with schematics.

“Back in 2019, while attending the annual AHR conference held in Orlando, the late great Les Nelson, who was the director of the Radiant Professionals Alliance, asked me what the RPA could do to help the hydronic industry,” said Mark Eatherton, service manager for Advanced Hydronics, Inc. and chairman of the Hydronics Standards Committee. “I told him that we were in dire need of a uniform hydronic systems water quality standard. The IAPMO/ANSI standard will advance the hydronics industry and can be adopted by all facets of the industry, from manufacturers to installers and end users, as well as jurisdictions across the country. This standard will ensure the life expectancy of these critical systems and provide many years of trouble-free operation.”

Founded in 1926, IAPMO seeks to be a worldwide leader in the plumbing and mechanical industry through the protection of health and safety. IAPMO develops industry standards with a focus on plumbing products, solar heating systems and components, mechanical products (including heating, ventilation, cooling and refrigeration system products) and products used in the recreational vehicle and manufactured housing industries.

For more than 30 years, IAPMO has developed plumbing product standards as American National Standards, initially as the secretariat for the ANSI Z124 Technical Committee in 1984, and since 2005 independently under its own American National Standards Institute (ANSI) accredited standards development procedures.

A copy of IAPMO/ANSI H1001.1 can be purchased through the IAPMO Online Store. For questions, please contact Taylor Costea, at (909) 218-8126 or taylor.costea@iapmo.org.


IAPMO develops and publishes the Uniform Plumbing Code®,the most widely recognized code of practice used by the plumbing industry worldwide; Uniform Mechanical Code®; Uniform Swimming Pool, Spa and Hot Tub Code®; and Uniform Solar Energy, Hydronics and Geothermal Code — the only plumbing, mechanical, solar energy and swimming pool codes designated by ANSI as American National Standards — and the Water Efficiency Standard (WE-Stand)™. IAPMO works with government, contractors, labor force, and manufacturers to produce product standards, technical manuals, personnel certification/educational programs and additional resources in order to meet the ever-evolving demands of the industry in protecting public health and safety.

Last modified: December 30, 2022