Heat transfer structure

Claim 2

A heat exchange system comprising: a first solid heat exchanger having a plurality of tubes interconnected by a plurality of thermally conductive bodies; one end of each of said tubes being connected to a first plenum at the lower end of said heat exchanger and the other end of each of said tubes being connected to a second plenum at the upper end of said heat exchanger; the upper ends of said tubes being above the level of the liquid in the second plenum; means for directing a gas heated by, and comprising the products of, combustion through passageways between said bodies; means for supplying a fluid as a liquid to the lower ends of said tubes to absorb heat from said bodies and to at least partially vaporize in at least portions of said tubes; a second heat exchanger positioned in said second plenum with the major portion of said second heat exchanger being positioned above and adjacent the upper ends of said tubes; said fluid being directed upwardly against portions of said second heat exchanger for transferring heat thereto; and means for returning the condensate of said vapor to the lower ends of said tubes.

Claim 3

The heat exchange system in accordance with claim 1 wherein said tubes have their upper ends extending into said second plenum which comprises a vapor collection dome.

Claim 4

The heat exchange system in accordance with claim 2 wherein the major portion of said tubes extending into said plenum are surrounded by said liquid.

Claim 5

The heat exchange system in accordance with claim 3 wherein said means for returning said condensate to the lower ends of said tubes comprises a condensate return pipe connected between said second plenum below the level of said liquid and its lower end connected to said first plenum for supplying the lower ends of said tubes with said liquid.

Claim 6

The heat exchange system in accordance with claim 1 wherein the heat is supplied to said gas by means of a burner controlled by the pressure in said dome.

Claim 7

The heat exchange system in accordance with claim 5 wherein said burner control comprises a pressure responsive switch.

Claim 8

The heat exchange system in accordance with claim 6 wherein at least the major portion of said second heat exchanger is positioned above said liquid in said dome.

Claim 9

The heat exchange system in accordance with claim 7 wherein said second heat exchanger comprises a coil of tubing.

Claim 10

The heat exchange system in accordance with claim 8 wherein said second heat exchanger is supplied with water from a cold water inlet and supplies hot water to an outlet.

Claim 11

The heat exchange system in accordance with claim 1 wherein a third heat exchanger external to said upper plenum exchanges heat between the output of said second heat exchanger and the input of said second heat exchanger.

Claim 12

The heat exchange system in accordance with claim 10 wherein the heat is supplied to said gas by means of a burner controlled by the pressure in said upper plenum.

Claim 13

The heat exchange system in accordance with claim 11 wherein said burner is controlled by a pressure responsive switch.

Claim 14

The heat exchange system in accordance with claim 10 wherein at least the major portIon of said second heat exchanger is positioned above the level of said liquid in said upper plenum.

Claim 15

The heat exchange system in accordance with claim 10 wherein said second heat exchanger comprises a coil of tubing.

Claim 16

The heat exchange system in accordance with claim 14 wherein said second heat exchanger is positioned substantially entirely above said liquid in said upper plenum.

Claim 17

A heat exchange system comprising: a first solid heat exchanger having a plurality of vertical tubes interconnected by a plurality of thermally conductive bodies; means for directing a heated gas through passageways between said bodies; means for supplying a fluid as a liquid to the lower ends of said tubes to absorb heat from said bodies and to at least partially vaporize in at least portions of said tubes; a second heat exchanger positioned within a dome and adjacent the upper ends of said tubes with said fluid transferring heat thereto; means for returning the condensate of said vapor from said dome to the bottoms of said tubes; said gas being heated by means of a burner controlled by the pressure in said dome; said burner control comprising a pressure responsive switch; said second heat exchanger being positioned above said liquid in said dome and comprising a coil of tubing; said second heat exchanger being supplied with water from a cold water inlet and supplying hot water to an outlet; and a third heat exchanger external to said dome for exchanging heat from the output of said second heat exchanger to the input of said second heat exchanger.

Claim 18

A heat exchange system comprising: a first solid heat exchanger having a plurality of vertical tubes interconnected by a plurality of thermally conductive bodies; means for directing a heated gas through passageways between said bodies; means for supplying a fluid as a liquid to the lower ends of said tubes to absorb heat from said bodies and to at least partially vaporize in at least portions of said tubes; a second heat exchanger positioned within a dome and adjacent the upper ends of said tubes with said fluid transferring heat thereto; means for returning the condensate of said vapor from said dome to the bottoms of said tubes; said gas being heated by means of a burner controlled by the pressure in said dome; said burner control comprising a pressure responsive switch; said second heat exchanger being positioned above said liquid in said dome and comprising a coil of tubing; said second heat exchanger being supplied with water from a cold water inlet and supplying hot water to an outlet; and a third heat exchanger external to said dome for exchanging heat from the output of said second heat exchanger to the input of said second heat exchanger.