The efficiency of a boiler is determined largely by the heat lost to any excess air supplied and the loss in high temperature flue gases. This calculator determines this efficiency from the CO₂ content of the flue gas and the flue gas temperature. At the same time it also indicates the percentage of excess air being supplied.

NOTE: The Calculator is based on gross calorific values. Gives answers for coal, coke, Town gas, natural gas, fuel oils - residual and distillate.
Size: 5.3/4" diameter single sided, complete in plastic case.