Variable stage direct field boiler

A boiler apparatus comprising:

• (a) a combustion chamber for receiving fuel and oxygen in sufficient quantitites to support combustion and for continuously receiving liquid water during combustion for conversion of same to steam, said combustion chamber including an output for exiting the atmospheric contents of said combustion chamber;
• (b) a plurality of combustion stages, each such stage including at least one burner located within said combustion chamber;
• (c) pressure sensing means operably connected to said output for sensing output pressure and to said combustion stages for controlling how many of said stages are operating at a given moment in response to output pressure;
• (d) a plurality of fuel valves, at least one each for each said combustion stage, such that the delivery of fuel to said burners may be selectively controlled by said pressure sensing means.
• (e) a plurality of water valves, at least one each for each said combustion stage, such that the delivery of liquid water to said combustion chamber for conversion to steam may be selectively controlled by said pressure sensing means;
• and
• (f) liquid-to-steam converter having pneumatic pathway formed therein, an input operably connected to said combustion chamber, and an output, such that atmospheric contents from said combustion chamber may be introduced into said converter and moved through said pneumatic pathway to thereby assist in converting any remaining liquid water particles to steam.