What specific hazard does a low-pressure switch prevent in a boiler?

A low-pressure switch in a boiler plays a critical role in maintaining safe operating conditions. It is specifically designed to prevent explosions that could occur due to low pressure conditions. When the pressure in the boiler drops below a certain threshold, the low-pressure switch will activate to shut down the burner or boiler operation to eliminate the risk of an explosive environment. This is crucial because boilers operate under high pressure, and any significant drop in pressure can lead to a lack of proper operation, which, if unchecked, could lead to dangerous situations.

In contrast, overheating of the boiler pertains to a different aspect of boiler operation and is typically managed by high-temperature switches or pressure relief valves. Likewise, excessive water levels are monitored through high-water level switches and float switches to ensure that the boiler operates within safe water level parameters. Loss of energy efficiency, while important for operational cost management, is not directly related to the safety functions provided by the low-pressure switch. Thus, the primary focus of the low-pressure switch is to address the hazards related to low pressure and prevent potential catastrophic failures such as explosions.