A new and improved incinerator steam generation system subjecting to combustion debris such as municipal waste, utilizing the heat derived therefrom to produce steam for steam boiler, electrical generating facilities, heating facility for industrial or commercial plants, and so forth. This is provided with a series of boilers and controls, both manually adjustable and also automatic, whereby the possibility of fire dangers are minimized, created temperature ranges of boiler gases are constrained to desirable limits, dump stack facilities are automatically controlled as to particular effectiveness for differing types of operating conditions, and where safety features are incorporated to shut down gas flow through the boiler during periods of boiler-water deficiency, excess steam generation relative to demand, and other conditions. Within the furnace area proper the pressure conditions are predetermined and are controlled during operation for desired efficiency, vapor removal, and materials' combustion. Thus, air-entrained particulates are minimized, and combustible gases as produced at the grate areas of the furnace are driven off for later, secondary combustion. Temperature control of resulting gases is maintained.