Class 5 Boiler Practice Exam 2025 - Free Boiler Certification Practice Questions and Study Guide

Neglecting boiler water treatment leads to the formation of corrosion and scaling within the boiler system, which represents a significant risk. When boiler water is not treated, impurities such as oxygen, carbon dioxide, and minerals can accumulate. These contaminants can react with the metal surfaces of the boiler, leading to corrosion. As corrosion progresses, it can compromise the integrity of the boiler, resulting in leaks or even catastrophic failures.

Additionally, scaling occurs when minerals precipitate out of the water and deposit on the heat transfer surfaces. This layer of scale acts as an insulating barrier, reducing the efficiency of heat transfer and forcing the boiler to work harder to maintain the desired output. Therefore, untreated water not only impacts the boiler's reliability and performance but also significantly increases maintenance costs and can shorten the lifespan of the equipment.

In contrast, the other options suggest positive outcomes that are highly unlikely to occur without proper water treatment, as neglecting treatment typically leads to detrimental effects and increased operational risks.