What is a key function of dielectric unions in plumbing?

Dielectric unions serve a crucial role in plumbing systems by preventing galvanic action, which is a type of corrosion that occurs when two dissimilar metals are in contact with each other in the presence of an electrolyte, such as water. This corrosion can lead to significant damage over time to the pipes and fittings, resulting in leaks and other plumbing issues.

The dielectric union acts as a barrier between these metals, typically using a non-conductive material to separate them. By doing so, it inhibits the electrical flow that causes galvanic corrosion, extending the lifespan of the plumbing system and maintaining its integrity.

The other options do not accurately reflect the primary function of dielectric unions. While they may relate to plumbing systems in a broader sense, they do not capture the specific purpose that dielectric unions serve.