Boiler Combustion Air Tune Up
The term “Make up air or “Excess air” is used to describe the extra air delivered to the burner as a margin of safety, ensuring that there is always more than enough oxygen (oxygen makes up 21% of air) to allow complete combustion of the fuel.
Controlling the amount of excess air is important to make certain that all of the fuel is burned. Combustion efficiency depends on mixing the right amount of air with the right amount of fuel. Boiler logs are used to spot trends that indicate reduced efficiencies or boiler failure. If vent stack temperatures are steadily increasing, efficiency has decreased. The rule-of-thumb is that the vent stack temperature should be +/-150 degrees higher than the steam or water temperature.
- Analyze oxygen and carbon dioxide at given stack temperatures to determine combustion efficiency.
- Make burner adjustments to air and fuel mixture to maintain efficient burn.