What additional protection does crosslinked polyethylene tubing (PEX) require if used in a radiant panel heating system?

Crosslinked polyethylene tubing (PEX) is widely used in radiant heating systems due to its flexibility, resistance to scale and chlorine, lower shipping costs, and ease of installation. However, one of its notable vulnerabilities is to oxygen migration. In radiant heating applications, oxygen from the surrounding environment can penetrate the PEX tubing, potentially leading to corrosion of metal components in the heating system.

To mitigate this issue, PEX tubing requires an additional protective layer. A protective coating specifically designed to minimize oxygen migration effectively creates a barrier. This coating helps ensure the longevity and reliability of the heating system by preventing the ingress of oxygen that could lead to rust and system failures over time.

In contrast, the other options—such as a steel casing, fiberglass insulation, or plastic covering—do not directly address the oxygen permeability issue that PEX faces in radiant heating systems. While these components may serve various purposes, such as structural support or thermal insulation, they do not provide the necessary protection against oxygen diffusion that is essential for maintaining system integrity.