The paper presents a set of tests with a setup using steam supply into ejector instead of compressed air. Experi-ments measured the gas analysis data - volumetric concentrations O-2, CO, CO2, C (n) H (m) , NO (x) , H-2 at different propor-tions of air and steam. The data are compared with calculations for thermodynamic equilibrium compositions for the reacting mixture D<inverted exclamation>+De(2)D+air performed by "Terra" computer code including the case of air excess (alpha ae<currency> 1). The cal-culations were also compared with available data on gasification output at a high content of ballasting gas. It was demonstrated that in these operation modes, the steam was an inert dilution agent, which did not exclude the outcome of coal gas production with high ratios corresponding to different modes of gasification.