What is the reason for using metal pans under water heaters?

Using metal pans under water heaters is primarily intended to prevent property damage from leaks. Water heaters can develop leaks due to various issues such as corrosion, overheating, or faulty components. When a leak occurs, having a metal pan in place catches the escaping water, effectively containing it and directing it to a drainage system or a designated area to minimize damage to the surrounding structures, flooring, and belongings. This precautionary measure is essential in residential settings, as it helps maintain the integrity of the home and can prevent costly repairs and health hazards associated with water damage and mold growth.

The other potential functions of metal pans, such as enhancing aesthetics or providing insulation, are secondary or not primary reasons for their use. While they may collect condensation to some extent, the primary reason for their installation in residential plumbing is to safeguard against leaks and their subsequent consequences.