Combustion Analyzer Residential/Commercial Fuel Type Natural Gas Propane Combustion Efficiency 0 to 99.9 Percent Oxygen Concentration 0 to 21 Percent Carbon Dioxide Concentration 0 to 20 Percent Carbon Monoxide Measurement Range 0 to 10 000 ppm Primary/Ambient Air Temp 32 Degrees to 112 Degrees F Stack Temp -40 Degrees to 950 Degrees F Pressure/Draft +/-0.4 in WC to +/-32 in WC Nitric Oxide Measurement Range 0 to 100 ppm Excess Air 0 to 250 Percent Display 6 Line Backlight