In a hot water heating boiler, what variable does the burner control sense?

In a hot water heating boiler, the burner control system primarily senses the boiler water temperature. This is crucial because the efficiency and safety of the heating system depend heavily on maintaining the appropriate water temperature. When the water temperature drops below a preset level, the burner control activates the burner to heat the water; conversely, when the desired temperature is achieved, the burner is turned off to save fuel and prevent overheating.

Monitoring the boiler water temperature allows for timely adjustments to ensure the system operates within safe and efficient parameters. This is essential for both energy conservation and preventing potential hazards associated with overheating, such as pressure build-up or system failure.

In contrast, while other variables like boiler pressure, water level, and fuel flow are important aspects of boiler operation, they are not the primary factors that the burner control actively senses to initiate or stop the burner function.