Which condition represents a significant risk during boiler operation?

Overheated tubes due to low water levels represent a significant risk during boiler operation primarily because this condition can lead to catastrophic failure of the boiler. When water levels drop significantly, the tubes that are designed to be cooled by the water can become exposed to the high temperatures of the burning fuel. Without the water to absorb and conduct heat away, the tubes can overheat rapidly, potentially leading to weakening or rupture of the metal. This overheating can cause structural damage and, in severe cases, result in boiler explosions or system failures, placing personnel and equipment at risk.

Maintaining proper water levels within a boiler is critical for safe operation. Adequate water levels also ensure effective heat exchange, prevent damage to the boiler components, and sustain the overall efficiency and reliability of the system. Thus, monitoring and managing water levels is a fundamental practice in boiler operation and safety protocols.