True or False: The presence of white smoke coming from a gas-fired burner indicates that the fuel-oil mixture is too lean.

The presence of white smoke from a gas-fired burner typically indicates that there is an issue with combustion, specifically that the fuel mixture may not be ideal for efficient burning. In the context of a gas-fired burner, white smoke can suggest that the fuel-air mixture is too lean, which means there is an insufficient amount of fuel relative to the air for combustion. This lean mixture can cause incomplete combustion, leading to the formation of water vapor and unburned hydrocarbons, which manifest as white smoke.

In a balanced combustion scenario, the correct ratio of fuel to air allows for complete combustion, producing minimal visible smoke and efficient energy output. When the mixture is too lean, however, it hinders the combustion process, resulting in higher levels of unburned fuel and byproducts, including the white smoke that is noticeable during operation.

This understanding is also tied to combustion efficiency and the proper functioning of the burner. Recognizing the implications of visible emissions like white smoke is critical for diagnosing issues with gas-fired heating appliances and ensuring they operate safely and efficiently.