The purpose of combustion analysis is to help HVAC technicians ensure fuel-fired heating appliances are running safely and efficiently. Long gone are the days of checking efficiency by the color and shape of the flame. Combustion analyzers measure and calculate a range of variables such as flue temperature, draft pressure, and the byproducts of combustion like oxygen (O2), carbon dioxide (CO2) and carbon monoxide (CO). To tap into the full power of your combustion analyzer, here are a few tips and best practices to keep in mind this heating season.