Joints between different metallic piping materials in hydronic systems shall be made with what fittings?

Joints between different metallic piping materials in hydronic systems shall be made with what fittings?

• A. Standard Threaded Fittings
• B. PVC Unions
• C. Compression Fittings
• D. Approved Dielectric Fittings And Brass Converter Fittings

Answer: (D)

The joints between different metallic piping materials in hydronic systems must use fittings that prevent galvanic corrosion by electrically isolating the metals. Dielectric fittings do this with a non-conductive barrier between the two metal sections, stopping the electrical path that drives corrosion. Brass converter fittings also provide a safe transition between dissimilar metals, reducing galvanic action while allowing a reliable connection. Using standard threaded fittings simply joins metals without isolation, which can allow galvanic corrosion. PVC unions aren’t suitable for metallic hydronic piping connections in typical hot-water or steam service due to temperature/pressure limits and compatibility issues. Compression fittings don’t inherently isolate dissimilar metals and thus don’t reliably prevent galvanic corrosion.

The joints between different metallic piping materials in hydronic systems must use fittings that prevent galvanic corrosion by electrically isolating the metals. Dielectric fittings do this with a non-conductive barrier between the two metal sections, stopping the electrical path that drives corrosion. Brass converter fittings also provide a safe transition between dissimilar metals, reducing galvanic action while allowing a reliable connection.

Using standard threaded fittings simply joins metals without isolation, which can allow galvanic corrosion. PVC unions aren’t suitable for metallic hydronic piping connections in typical hot-water or steam service due to temperature/pressure limits and compatibility issues. Compression fittings don’t inherently isolate dissimilar metals and thus don’t reliably prevent galvanic corrosion.