O2 or CO2 measurements are used to calculate what?

O2 or CO2 measurements are primarily used to calculate excess air in combustion processes. When fuel is burned, it requires a certain amount of oxygen to combust efficiently. However, in practice, more air than the stoichiometric requirement is often supplied to ensure complete combustion and to avoid the formation of pollutants.

By measuring the oxygen or carbon dioxide in the flue gases, technicians can determine how much excess air is being used. This information is critical, as too much excess air can lead to reduced combustion efficiency and increased energy costs, while too little can result in incomplete combustion, leading to harmful emissions and inefficiency.

Excess air is essential for achieving optimal combustion since it ensures that the fuel is fully burned, thereby reducing the production of carbon monoxide and other pollutants. Hence, the measurements of O2 and CO2 directly relate to the severity of excess air in a combustion system, allowing for adjustments to improve performance and efficiency.