🔍 Key Concepts
• Straight mechanical atomization requires proper fuel pressure at the burner – think about how that pressure is built up in this system.
• Look at how fuel flows from the pumps and heaters toward the boiler front; notice which labeled valves (A, B, C, D, E, F, G, H, J) are on recirculating/bypass lines versus those on supply lines to burners.
• Consider which valve position must change just before light‑off so that fuel stops recirculating and is directed to the burner tips.
đź’ Think About
• Trace the fuel path from the settling tank through the pumps and heaters to the boiler burner front; where does the fuel go before light‑off, and where must it go during light‑off?
• Which of the labeled valves, if left open, would prevent sufficient pressure at the burner because it allows fuel to continue to bypass or recirculate?
• Among A, B, C, D, E, F, G, H, J, which one is closest to the boiler burner front and clearly associated with a return/recirculation line rather than the main supply line?
âś… Before You Answer
• Verify which line is the return/recirculation line leading away from the burner front back toward the system or tank.
• Confirm which labeled valve, when closed, forces fuel to go to the burners instead of returning/recirculating.
• Make sure the valve you select is not one that would shut off all fuel supply to the boiler but instead one that specifically stops bypass flow just prior to ignition.