What is the main function of a circulating pump in a boiler system?

The main function of a circulating pump in a boiler system is to circulate water or steam throughout the system. This ensures that the heated water or steam produced by the boiler is efficiently distributed to various parts of the heating system—such as radiators or heat exchangers—allowing for effective heat transfer. By continuously moving the water or steam, the circulating pump helps maintain consistent temperatures throughout the system and prevents stagnation, which can lead to inefficiencies or operational issues.

In contrast, the other options refer to different aspects of boiler operation. Regulating fuel supply focuses on ensuring the right amount of fuel is available for combustion, which is not the role of a circulating pump. Maintaining water levels is related to the control of the boiler’s water supply to prevent issues like boil dry or excessive water, which is managed by different mechanisms, often involving water level controls and sensors. Removing air from the system is a separate process known as venting or deaeration, which is important for system efficiency but does not pertain to the primary function of the circulating pump.