Italian Boiler


This is a commercially available steam cleaner manufactured in Italy.  It has a 12 volt blower and burner.  The heat exchanger consists of two helically wound coils.  The whole thing is air jacketed with the fan blowing combustion air into the jacket which both cools the outer housing and pre-heats combustion air.  The pressure atomizing nozzle and sparker ignition is located at the far end of the unit with the combustion chamber in the center and flow of combustion gases up past one coil and down past the other one. 
  italian boiler

This type of flow does not make for efficient heat exchange and it appears that quite a bit of heat goes up the chimney.  That is because it is not a true counter-flow such as we have in most all mono-tube boilers.  However, it is compact, very easy to manufacture because a helical coil is always easier to wind than a pancake coil.  It contains its own fuel pump and nozzle, for kerosene, blower fan, and sparker igniter, thus making it a nice unit for making steam.  A water pump and some control system is needed.