What does a color other than blue in a flame typically indicate?

A flame that exhibits a color other than blue typically indicates incomplete combustion. In a gas appliance, a blue flame is associated with proper combustion, indicating that the fuel is burning efficiently and completely with a balanced air-to-fuel ratio. When the flame turns yellow, orange, or has a noticeably different color, it signifies that there is insufficient oxygen for complete combustion, which can lead to the production of carbon monoxide and other harmful byproducts. Recognizing this visual cue is vital for ensuring safety and efficiency in gas systems, as incomplete combustion not only compromises the performance of the appliance but also poses health risks due to potential carbon monoxide emissions.