What can cause incomplete combustion in a boiler?

Incomplete combustion in a boiler typically occurs when there is not enough air supplied for the combustion process. For fuel to burn efficiently, oxygen is essential. If the amount of air is insufficient, it leads to a situation where the fuel does not fully react, resulting in incomplete combustion. This can produce undesirable byproducts, such as carbon monoxide, and can affect the overall efficiency of the boiler.

While excessive fuel supply can contribute to inefficient combustion, it is the lack of adequate air that primarily leads to incomplete combustion. High pressure and high temperature generally favor the combustion process; therefore, they are less likely to cause incomplete combustion as they typically assist in improving fuel burning efficiency.