The Worcester Bosch spare is for use in the gas assembly of the brand's 240, 280, CDi Series, i Junior Series, i Series, and 230 boiler ranges. The gas valve is employed in the distribution of gas. When gas is required in the burner, the printed circuit board sends a signal to the gas valve, which opens to allow gas to flow into the burner or the pilot assembly depending on the model of the appliance. It carries the widest range of spares.