Which component is activated to ignite the pilot gas valve in a natural draft gas fired boiler?

In a natural draft gas-fired boiler, the component that activates the pilot gas valve is critical for ensuring safe and effective operation. The load relay plays a key role in the ignition sequence, as it is responsible for controlling the electrical function of various components during the starting process. When the boiler control system determines that conditions are appropriate for ignition, the load relay provides the necessary voltage to open the pilot gas valve. This allows gas to flow to the pilot burner, where it can be ignited to initiate the combustion process.

The ignition transformer is important for generating the high voltage needed to create a spark or arc for igniting the gas, but it is not responsible for activating the gas valve itself. The flame detector is designed to monitor whether a flame is present after ignition has occurred, and the main gas valve controls the gas supply to the burner, but its operation is typically coordinated with the pilot gas valve as part of the larger ignition sequence. Therefore, understanding the role of the load relay clarifies its importance in activating the pilot gas valve in a natural draft gas-fired boiler.