Metallic pipe supports must not promote galvanization.

• A. True
• B. False
• C. Sometimes
• D. Not allowed

Answer: (A)

The main idea is galvanic corrosion and the need to electrically isolate different metals in a damp HVAC environment. When two dissimilar metals are in direct contact and there is an electrolyte (like condensate or humidity), a galvanic cell forms: one metal becomes the anode and corrodes faster, while the other is protected. Metallic pipe supports that touch the pipe can create this unwanted galvanic action, accelerating corrosion on one of the metals. To prevent that, you use insulating spacers, non-metallic supports, or coatings so the pipe and the support don’t form a conductive pair. Because the goal is to avoid promoting galvanic action, the statement that metallic pipe supports must not promote galvanization aligns with good practice. If metals are compatible or properly isolated, galvanic corrosion is minimized.