Patent ID: 7819090

Claim:
A heat exchange apparatus, particularly a fire tube condensing boiler, provided with a structure made of carbon steel and comprising an outer enclosure, which is adapted to delimit a portion of space for containing a fluid to be heated, which is fed cold by means of an intake coupling located proximate to the base and flows out hot through a discharge coupling located proximate to the top of the enclosure, said portion of space being crossed by flue gas conveyance tubes that are connected at a lower end of a furnace that accommodates a burner, further comprising a bell-shaped element, which is located proximate to the top of said portion of space and is open at the lower end and closed at the upper end, said bell-shaped element being provided with a thermostatic device which is adapted to allow the fluid contained therein to flow out when it reaches a preset temperature, said bell-shaped element enclosing said furnace that accommodates said burner.