Boiler

Claim 1

IN A BOILER FOR PRODUCING HOT WATER OR STEAM, A HEATING STRUCTURE COMPRISING A COMBUSTION CHAMBER AND A HEAT EXCHANGER FORMED BY A PLURALITY OF INDEPENDENT INTEGRAL HEAT EXCHANGE UNITS EACH ADAPTED TO BE CONNECTED AT THEIR LOWER PORTIONS TO A COMMON SUPPLY MANIFOLD AND ADAPTED TO BE CONNECTED AT THEIR UPPER PORTIONS TO A COMMON RETURN MANIFOLD, A FIRST OF SAID UNITS INCLUDING A FRONT UPRIGHT WATER COMPARTMENT WITH A PAIR OF SPACED UPRIGHT SIDE WATER COMPARTMENTS EXTENDING REARWARDLY THEREFROM ALONG OPPOSITE SIDES OF THE BOILER, SAID FRONT COMPARTMENT AND SAID PAIR OF SIDE COMPARTMENTS DEFINING A GENERALLY U-SHAPED UNIT AS SEEN IN PLAN VIEW AND FORMING THE FRONT AND SIDE WALLS OF THE COMBUSTION CHAMBER, A SECOND OF SAID UNITS INCLUDING A MAIN UPRIGHT WATER COMPARTMENT EXTENDING TRANSVERSELY OF THE BOILER AND FORMING THE REAR SURFACE OF THE COMBUSTION CHAMBER, SAID SECOND UNIT INCLUDING A FIRST NEST OF UPRIGHT PLANAR WATER CONTAINER ELEMENTS PROJECTING FORWARDLY FROM THE UPPER PART OF SAID MAIN COMPARTMENT ABOVE THE COMBUSTION CHAMBER, SAID FIRST NEST FITTING INTO SAID FIRST U-SHAPED UNIT BETWEEN THE SIDE COMPARTMENTS AND PROVIDING UPWARDLY EXTENDING PASSAGES FOR THE HOT GASES BETWEEN SAID ELEMENTS, SAID SECOND UNIT ALSO INCLUDING A SECOND NEST OF UPRIGHT PLANAR WATER CONTAINER ELEMENTS PROJECTING REARWARDLY FROM SAID MAIN COMPARTMENT AND PROVIDING DOWNWARDLY EXTENDING PASSAGES FOR THE HOT GASES BETWEEN SAID LATTER ELEMENTS, MEANS CONVEYING HOT GASES FROM THE TOP OF SAID FIRST NEST TO THE TOP OF SAID SECOND NEST, AND A THIRD OF SAID UNITS INCLUDING AN UPRIGHT WATER COMPARTMENT EXTENDING TRANSVERSELY OF THE BOILER WITH A SECOND PAIR OF SPACED UPRIGHT SIDE WATER COMPARTMENTS EXTENDING FORWARDLY THEREFROM ALONG OPPOSITE SIDES OF THE BOILER AND DEFINING A GENERALLY U-SHAPED UNIT AS SEEN IN PLAN VIEW, SAID SECOND NEST FITTING INTO SAID THIRD U-SHAPED UNIT BETWEEN SAID SECOND PAIR OF SIDE COMPARTMENTS.