Home Inspection State Practice Exam

The flame from a properly adjusted oil burner should be what color?

1. Red

2. Blue

3. Yellow

4. White

The correct answer is: White

The flame from a properly adjusted oil burner should be blue. A blue flame indicates that the oil is burning efficiently with complete combustion, which produces minimal soot and maximizes heat output. This color is a sign of optimal fuel-to-air mixture and indicates proper functioning of the burner. In contrast, a yellow flame often signifies incomplete combustion or the presence of impurities in the fuel, which can lead to soot buildup and reduced efficiency. A red flame may indicate a burning issue or inefficiency as well, typically related to the presence of heat and lower combustion efficiency. A white flame is not typically associated with oil burners but can be found in other types of combustion processes, such as gas burners under certain conditions. Therefore, the most accurate color signaling a properly adjusted oil burner is blue.