A hot-wall furnace of 40 ft(3) fired with sorbent-loaded coal-water fuels at 1 MMBtu/h was found to generate firing and efficiency (performance) curves in functional agreement with the equations developed in furnace analysis. (In the FPS system, M = 1000 and MM = 1 000 000. It is based on the Latin prefix, M, as abbreviation for mille.) The present study includes a theoretical correction for the dependence of the firing parameters on excess air due to water in the fuel, and this correction is shown to be supported by test against the experimental results. The complete results show the variation with output of : thermal input (firing curve), thermal (operational) efficiency, heat utilization factor,specific gas enthalpy, and wall loss. The furnace analysis firing constants were obtained from the experimental results for the variation with output of the heat utilization factor, and crosschecked against the data for the-variation of specific gas enthalpy with output. With corrections to the excess air values for water in the fuel, the intrinsic efficiency and maximum output values obtained are then shown to fall and rise linearly with, respectively, effective excess air and equivalence ratio, in support of prediction. The values of the firing parameters were used to calculate the firing and efficiency curves at 0%, 15%, 30%, and 45% excess air,with acceptable agreement between the predictions for these conditions and the experimental results for data within bands defined by the four excess air levels. With a data base of about 7000 measurements, these experiments have permitted better evaluation and test of the excess-air function in the furnace analysis equations, including the correction for the effective excess air addition required to account for water in the fuel mixture.