🔍 Key Concepts

• Proper air-fuel ratio in boiler combustion • Effects of excess air versus insufficient air on flame stability • How fuel pressure and temperature affect atomization and smooth burning

💭 Think About

• Think about what makes a flame burn smoothly and steadily versus what would make it surge, rumble, or "breathe" in and out. • Which condition would lead to intermittent or uneven combustion in the furnace rather than a clean, continuous burn? • How do low fuel pressure or temperature affect droplet size and ignition, and how does that compare with the effect of too much or too little air?

✅ Before You Answer

• Compare symptoms of poor atomization (low fuel pressure/temperature) with symptoms of poor air control (too much or too little air). • Decide whether pulsation is more likely from a flame that is starved of oxygen or one that is well-supplied with oxygen but not burning uniformly. • Eliminate any options that would more likely cause a weak, smoky flame rather than a strongly pulsating one.