What is the function of a sequential draft control on a rotary cup oil-fired boiler?

What is the function of a sequential draft control on a rotary cup oil-fired boiler?

• A. Maintain constant fuel flow
• B. Regulate combustion air
• C. Close the automatic damper after the burner cycle
• D. Open the damper during ignition

Answer: (C)

The function of a sequential draft control on a rotary cup oil-fired boiler is primarily to close the automatic damper after the burner cycle. This mechanism helps ensure that the system effectively contains combustion gases and maintains proper combustion efficiency when the burner is not in operation. By closing the damper after the ignition cycle is complete, the sequential draft control prevents air from entering the combustion chamber and reduces the chance of flame blowout or unstable combustion during shutdown periods. Each of the other options relates to different operational aspects of the boiler but does not specifically address the sequential function of the draft control. Maintaining constant fuel flow is crucial for operation but is not the primary focus of sequential draft control. Similarly, regulating combustion air is essential during the burning process, but that function tends to be managed by other components of the boiler system. Opening the damper during ignition occurs but is part of separate control mechanisms involved in initiating combustion. Thus, the sequential draft control specifically emphasizes the closure of the damper once the burner cycle is finished.

The function of a sequential draft control on a rotary cup oil-fired boiler is primarily to close the automatic damper after the burner cycle. This mechanism helps ensure that the system effectively contains combustion gases and maintains proper combustion efficiency when the burner is not in operation. By closing the damper after the ignition cycle is complete, the sequential draft control prevents air from entering the combustion chamber and reduces the chance of flame blowout or unstable combustion during shutdown periods.

Each of the other options relates to different operational aspects of the boiler but does not specifically address the sequential function of the draft control. Maintaining constant fuel flow is crucial for operation but is not the primary focus of sequential draft control. Similarly, regulating combustion air is essential during the burning process, but that function tends to be managed by other components of the boiler system. Opening the damper during ignition occurs but is part of separate control mechanisms involved in initiating combustion. Thus, the sequential draft control specifically emphasizes the closure of the damper once the burner cycle is finished.