2024 Uniform Solar Energy Hydronic Code

The Uniform Solar Energy and Hydronic Code is a model code developed by IAPMO to govern the installation and inspection of solar, hydronic, and geothermal energy systems as a means of promoting the public’s health, safety and welfare. 

Key provisions of the 2024 USEHC and changes from the 2021 edition include:

• Hydronic Fluid Safety: New strict requirements for heat transfer fluid quality, freeze protection, and disposal.
• System Material Updates: New material standards, joining methods, minimum bend radii for PE/PEX piping, and provisions to prevent oxygen diffusion corrosion.
• Component Changes: Upgraded specifications for fluid expansion storage systems and hydronic expansion tanks.
• Safety & Support: Added hanger and support requirements for PE-RT and PEX systems, as well as protective barrier requirements for energy storage systems in garages.

About IAPMO

Short Bio of Authors: International Association of Plumbing and Mechanical Officials (IAPMO) was founded in 1926, IAPMO aims to advance improved sanitation methods and promote the welfare of builders, owners, and craftsmen. The organization focuses on developing uniform codes and standards to protect public health and safety in plumbing and mechanical systems. IAPMO’s mission includes fostering harmony among stakeholders and ensuring the effective application of plumbing regulations.

Other Works:

• 2012 Uniform Solar Energy Hydronic Code
• 2015 Uniform Solar Energy Hydronic Code
• 2018 Uniform Solar Energy Hydronic Code
• 2021 Uniform Solar Energy Hydronic Code
• 2021 Uniform Plumbing Code
• 2024 Uniform Plumbing Code