What is the function of a combination fan limit control?

The function of a combination fan limit control is to manage the operation of the blower and protect the system from overheating. This device is crucial in heating systems, as it ensures that the blower operates at the correct times to effectively circulate heated air throughout the space. When the temperature rises above a predetermined limit, the fan limit control will shut off the burner, preventing potential damage from overheating and ensuring safe operation. This dual functionality helps maintain a consistent and safe temperature within the heating system.

Other options address functions that are not typically associated with the combination fan limit control. For example, controlling the heating element refers to a different part of the heating system, while determining water temperature is specific to water heating systems rather than air circulation. Additionally, maintaining system pressure relates more to gas supply systems or certain types of heating systems rather than the operations governed by a fan limit control. This clarity illustrates the importance and specificity of the combination fan limit control's role in a heating system's safety and efficiency.