Flame retention oil burners have what effect on flame temperature compared with conventional burners?

• A. They produce a cooler flame
• B. They produce a flame hotter by 300-500 F
• C. They produce the same temperature
• D. They do not produce flame

Answer: (B)

Flame retention oil burners are designed to hold and extend the flame in the combustion zone, which improves the mixing of atomized fuel with air and increases the residence time of fuel in the flame. This leads to more complete combustion and a higher energy release concentrated in the flame, so the peak flame temperature ends up higher than with a conventional burner. The hotter flame is typically around 300–500°F higher. If the flame were cooler or the same as a conventional burner, it would suggest poorer mixing or insufficient residence time, which isn’t the case with correctly functioning flame retention burners. They are designed to produce a stronger, hotter flame rather than a cooler or identical-temperature flame.