What ingredient should never be used to clean brass LPG fittings?

Using ammonia to clean brass LPG fittings is problematic because it can cause severe corrosion. Brass is an alloy primarily made of copper and zinc, and ammonia reacts with zinc, leading to dezincification, which significantly weakens the material. This process is particularly concerning for fittings, as structural integrity is critical for safety in gas systems.

The use of ammonia can create a risk of leaks or catastrophic failures when applied to LPG fittings, making it crucial to avoid this substance in maintenance practices. In contrast, other cleaning agents like soap, vinegar, and water can be safely used, as they do not react negatively with the materials in brass fittings.