Abstract: An improved swimming pool/spa water heating system whereby a portion of the water flow into the main heater unit (3), is preheated, thereby decreasing the time of operation of the main heater unit (3), to raise the pool water temperature to the desired temperature. The system improvement includes an arrangement wherein pool water is drawn from the pool by the water pump (22), and a portion of the water is diverted through a supplementary heater unit (27), which is located in the combustion exhaust stream of the main heating unit (3). The diverted water is thus preheated in the supplementary heater unit (27), by the residual heat in the main heater unit exhaust and is then directed back into the water system, at a point prior to the inlet of the main heater unit (3), and mixes with the remaining water in the system, thereby increasing the temperature of water into the main heater unit (3).

Abstract: An improved Cyclone furnace particularly suitable for retrofit applications to an existing boiler incorporates a Cyclone furnace and an integrated de-slagging chamber as a single manufactured piece. The Cyclone furnace and the de-slagging chamber are provided with a water cooling circuit which is separate from a water cooling circuit of the existing boiler to which it may be coupled, permitting the improved Cyclone furnace to be easily retrofitted to existing boilers or furnaces, even those not originally designed for Cyclone firing.

Abstract: A waste heat boiler for cooling a hot process stream includes a plurality of heat exchanging tubes within a cylindrical shell, an outlet chamber for withdrawing the cooled process stream, an insulated by-pass tube having an outlet end in the outlet chamber, and an injection nozzle in the outlet chamber for control of flow of the hot process stream through the by-bass tube by injection of a fluid into the by-pass tube outlet end.

Abstract: A thermal protective barrier is provided for space heating units in the form of a relatively thin panel having an interior volume filled with a non-combustible liquid (water and/or antifreeze mix, etc.). Two of the embodiments are flat and are adapted to be placed beneath and about the sides of a stove or other heating unit, with a third embodiment having a toroidal cross section and being adapted for installation about the flue of such a stove or heater. Additional structure may be installed within the panels to provide additional support, as required. The panels may be removably installed between the stove and adjacent walls and the underlying floor, or may be permanently installed integrally with the building structure. The panels may also include decorative coverings for exposed surfaces, if desired. The panels may be independent of other water or fluid systems, or may be interconnected with a water heater or hot water heating system, if desired.

Abstract: Heat recovery apparatus for extracting heat from a hot flue gas stream especially useful on a marine vessel. The apparatus includes a housing having opposite outer end walls, opposite outer side walls, a top wall and a bottom wall with a heat exchanger extending between the end walls spaced downwardly below the top wall, above the bottom wall and inwardly of the outer side walls. An inlet chamber is formed in the housing having an inlet opening in one of the end walls above the heat exchanger for receiving the hot flue gas stream and the inlet chamber includes a downwardly sloping wall for directing the incoming hot flue gas stream to flow downwardly through the heat exchanger toward the bottom wall. A pair of inner side walls are provided on opposite sides of the heat exchanger spaced inwardly of the outer side walls for directing the hot flue gas stream downwardly through the heat exchanger to a low level above the bottom wall.

Abstract: A heat recovery system for a boiler has a tank separator connectable to a boiler and receiving a liquid from the boiler as well as separating the liquid into a blow down liquid and a flush vapor, a heat exchanger having an upstream portion and a downstream portion and receiving a make up water to be heated, the tank separator being connected with the upstream portion of the heat exchanger so as to apply hot blow down water into the upstream portion of the heat exchanger therefore to heat the make up water in the upstream portion of the heat exchanger by heat given out by the blow down water, the heat exchanger further having a downstream portion connected with the upstream portion so that the make up water heated by the heat given out by the blow down water further flows into the downstream portion of the heat exchanger, the tank separator being connected with the downstream portion of the heat exchanger so as to supply the flush steam into the downstream portion of the heat exchanger and further heat the mak

Abstract: A pool heating and circulating system incorporates an internal combustion engine that drives a pump for developing a flow of water. The internal combustion engine has associated therewith an exhaust pipe which is connected to a heat exchanger. An outlet of the pump is also connected to the heat exchanger such that the water extracts the heat generated by operation of the internal combustion engine. The water flowing out of the heat exchanger is then delivered to a filter and a return line. A heat insulating shield is provided about the exhaust pipe to shield the exhaust pipe from excess exposure to cool air. A bypass line can be provided between the outlet of the pump and the heat exchanger so that water can bypass the heat exchanger and flow directly to the return line and filter when it is determined that the pool water temperature is at a desirable temperature. A valve is actually positioned in the bypass line to vary the flow through the heat exchanger.

Abstract: A device for increasing efficiency of a power plant operated by burning fossil fuel has a boiler for heating a process medium. An inlet line is connected to the boiler for feeding a first process gas in the form of combustion air into the boiler. An outlet line is connected to the boiler removing a second process gas in the form of flue gas from the steam generator. A heat exchanger for heating the combustion air by regaining some of the heat contained in the flue gas is provided. At least one device for preheating the combustion air is connected upstream of the heat exchanger. The device for preheating the combustion air preheats the combustion air with heat energy contained in the process medium which is at a low pressure level. At least one device for transferring a portion of the heat energy, introduced into the combustion air by preheating, from at least one of the process gases to the process medium at a high pressure level is provided.

Abstract: Waste heat boiler comprising within a cylindrical shell a plurality of heat exchanging tubes having an inlet end and outlet end;attached to the shell, means for introducing water on shellside of the tubes;means for introducing a hot process stream into the inlet end of the tubes and passing the gas stream through the tubes in indirect heat exchange with the water on the shellside of the tubes to produce water/steam and to cool the introduced process stream;means for withdrawing produced water/steam, and means for withdrawing the cooled gas stream;wherein the tubes are arranged in at least two tube bundles each of which is provided with means for adjusting flow distribution and flow rate of the hot gas stream between the tube bundles to control the production of steam and the cooling of the process stream.

Abstract: A heat recovery apparatus for increasing the efficiency of a furnace having a cold air return, a burner, a hot air outlet, and a hot air exhaust. The heat recovery apparatus comprising a finned coiled heat exchanger located in the exhaust and having a water inlet and a water outlet. The water outlet connected via a silicone tube to a second water inlet on a core heat exchanger located in the cold air return. The core heat exchanger having a water outlet connected via second silicone tube to a water reservoir tank. The water reservoir tank containing water and a pump submerged within the water. The pump having a third water inlet and a third water outlet. The third water outlet being connected via a third silicone tube to the water inlet of the coiled heat exchanger. The heat recovery apparatus increasing the efficiency of a non-high efficiency furnace.

Abstract: An apparatus for recovering heat, and a flue gas recovery and/or recirculation and/or induced draft apparatus for boilers. The apparatus for recovering heat may be used in combination with the flue gas recovery and/or recirculation and/or induced draft apparatus for boilers. The flue gas recovery and/or recirculation and/or induced draft apparatus receives combustion gases from the apparatus for recovering heat and recirculates a portion of the combustion gases to a burner of a boiler and transmits the remaining portion of the combustion gases through a flue that communicates with the atmosphere.

Abstract: A heating system comprises an oven located above a solid fuel stove, a chimney for receiving combustion gases from the solid fuel stove, and a heat exchanger in the chimney for transferring heat from the combustion gases to a flow of water. A heat exchange passage adjacent a water tank receives combustion gases from the stove and transfers heat from the combustion gases to water in the water tank. A damper is adjustable for controlling the flow of the combustion gases to the chimney and to the heat exchange passage.

Abstract: A single-drum recovery boiler comprising a superheater (2), boiler bank elements (3a) forming a boiler bank, and elements (3b) forming an economizer. In the recovery boiler, a plurality of boiler bank elements (3a) and economizer elements (3b) are disposed alternately so that a boiler bank--economizer unit (3) is achieved where the ratio between the boiler bank elements and the economizer elements is optimized in relation to the operating conditions of the boiler.

Abstract: A water tube boiler comprises a furnace having a burner and a vertical flue gas stack located to one side of the furnace. A convection tube assembly is arranged in the stack for the recovery of heat from flue gases passing through the flue gas stack. With the object of facilitating any repair work needing to be performed on the convection tube assembly, the tube assembly comprises by a plurality of parallel rows of vertical convection tubes which are provided externally with surface enlarging elements e.g. in the form of pins, along part of the height of each tube. The tubes in each row are joined together to form a coherent flat unit with the aid of a respective upper, horizontal header to which all convection tubes in the row are connected at their upper ends, and a respective lower horizontal manifold to which the bottom ends of the tubes in the row are connected.

Abstract: An apparatus for separating and recovering effluent gases from a furnace includes a pressure vessel for containing the gases. This vessel has a fluid input for receiving the gases and a fluid output for selectively removing the gases when they are separated. A condenser is provided to transform and maintain the lowest vapor pressure gas as a liquid so that it accumulates as a liquid at the bottom of the vessel. The remaining non-condensed effluent gases accumulate in strata above the liquid. Apparatus is provided to selectively remove the liquid and at least one of the remaining non-condensed gases from the vessel through the fluid output. Also set forth is a method for recovering effluent gases from a furnace including the steps of adding the gases to a pressure vessel, altering the density of the gases so that the lowest vapor pressure gas condenses into a liquid and the non-condensed gases stratify above the liquid. Then the liquid is removed from vessel and optionally expanded to cool the vessel.

Abstract: An efficient compact modulating or fixed firing rate hydronic heater is provided. A slotted single piece baffle encloses the heat exchange surface which is a wound finned tube, and improves gas flow contact with the heat exchange surface, thereby increasing the efficiency of heat transfer.

Abstract: A waste energy hot water heater which extracts heat energy through heat exchange with flue gas from a primary heating device is disclosed. The water heater has an easily removable, compact, and simple heat exchanger and a flue gas bypass system to avoid overheating the heat exchanger.

Abstract: A heating apparatus including a burner and a heat exchanger wherein the burner supplies a primary fluid and exhaust gas to the heat exchanger. Secondary fluid supplied to the heat exchanger is first heated within the heat exchanger by the primary fluid and then is further heated within the heat exchanger by the exhaust gas.

Abstract: A heat feeding apparatus employable for an internal combustion engine having a supercharger attached thereto, the apparatus including a compressed air bypass passage opening/closing valve disposed midway of a compressed air bypass passage by way of which the outlet of a blower is communicated with the inlet of a turbine in the supercharger and combustion means installed in an inlet region of the turbine, wherein opening or closing of the compressed air bypass passage opening/closing valve and combustion in the combustion means are initiated in dependence on the temperature of a specific kind of medium for which heat exchanging is effected in a heat exchanger, whereby a heat involved in the exhaust gas is transmitted to the heat exchanger in dependence on the demand required by the medium.

Abstract: An emissionless furnace boiler and effluent gas recovery system includes a pressure vessel having a fluid input and fluid output. The system is capable of maintaining an entropy characteristic equal to at least the condensing pressure of the lowest entropy gas of the gases constituting a processed effluent gas discharge. There is also provided a hollow, annular jacket having a surface in thermal communication with the pressure vessel, the jacket having an axis in substantial alignment with the gravity vector and the jacket including a fluid input and fluid output. The system also includes a fluid path beginning internally of said pressure vessel, passing through the vessel, through the fluid output means, continuing externally of the vessel, and extending between the vessel and the input of the jacket. Within the fluid path, but prior to the input of the jacket, there is provided an expansion valve for selectively changing the volume of fluid flowing from the vessel prior to its entry into the jacket.

Abstract: An engine preheating device for heating internal combustion engines prior to operation utilizes a propane torch and conventional propane supply tank. A hollow cylindrical housing is supported in upright orientation by a plurality of circumferentially spaced support legs. A helical heat exchanger coil is disposed in coaxial relation within the housing. An inlet conduit is coupled to a bottom end of the coil and an outlet conduit is coupled to an upper end of the coil. Quick connect couplings secure the inlet and outlet conduits to a water jacket of an internal combustion engine. An arcuate tubular elbow has a first end mounted in coaxial relation within the bottom end of the housing. A propane torch head is inserted within the elbow and is connected by a conduit to a propane supply tank. A flame diffuser is suspended within the coil by a tube connected to a top cover.

Abstract: This gas-powered apparatus comprises a substantially cylindrical combustion chamber having an inlet for the combustion air connected to the outside and an upper outlet connected to a burned gas flue. A tank is arranged around the combustion chamber and defines therewith an interspace, so that the water in the tank can be heated substantially by radiation. The interspace is downwardly connected to a duct having an opening for a fan sucking air from the enclosed space through the interspace and returning it to the enclosed space.

Abstract: A cyclone separator formed by a plurality of parallel tubes. A portion of the tubes form a cylinder, a portion are bent radially inwardly to form a roof and a portion are bent to form a hopper. Water is passed through tubes to cool the separator.

Abstract: A supplementary hot water heating system which transfers to a hot water tank heat from exhaust gas in the furnace stack which would otherwise be wasted. When the water in the supplementary heater core is heated to a desired temperature, normally closed valves, one connecting the heater core to the cold waterline and the other connecting the bottom of the hot water tank to a drain, are simultaneously opened and remain opened until the supplementary heater core is again filled with cold water from the cold water line.

Abstract: An improved gas-fired heater for supplying heat to a space, such as a vehicle cab, and simultaneously, heat to the engine block for running the vehicle. A heat exchanger simultaneously heats a coolant which supplies heat to the engine block, and air to the vehicle cab.

Abstract: An apparatus and method for conditioning air is disclosed. The invention captures condensation from an evaporator coil and pumps the chilled condensation through a coil to precool the air before the air flows over the evaporator coil. During a heating cycle, the invention captures waste heat from the furnace with a radiator system which includes through the coil to warm the air as it flows through the air handling unit.

Abstract: This disclosure relates to a heating system for a building having a chimney, which heating system incorporates a heat collecting recovery unit including a recovery exchanger set atop the chimney, an underground reservoir, a circulating pump, and an exchanger disposed to reject heat to the conditioned space within the building, to serve in combination to heat the building with energy which had theretofore been wasted, so that the energy consumption rate required for heating can be reduced.

Abstract: The present invention relates to a method for recovering heat and separating substances from a flue gas streaming through a heat exchange apparatus comprising a casing with heat exchange elements inserted thereinto, a medium being provided for absorbing heat from the flue gas. According to the invention the medium that shall absorb heat from the flue gas is conducted through the heat exchange elements, the heat exchange elements and the connections to the casing for flue gas being so placed that the flue gas streams perpendicularly to the heat exchange elements, the flue gas being given a flow velocity cross the heat exchange elements of not more than 3 m/sec. Soot in the flue gas is collected on the heat exchange elements and adsorbs and/or dissolves gaseous substances such as sulphur dioxide. The invention also relates to an apparatus for carrying out the method.

Abstract: A condensate drain system for a furnace incorporates a collector and blower housing assembly mounted above a secondary condensing heat exchanger with condensate ports between the blower housing and the collector housing positioned to assure flow of all condensate from the exhaust flue and the blower housing to the collector housing. A pipe extends downwardly from the collector housing to the condenser outlet manifold so that all condensate ultimately flows to the condenser outlet manifold and can be discharged to a drain by a single tube.

Abstract: Apparatus utilizing waste heat from a furnace or the like to heat water for any desired purpose or to supplement a conventional heating system. In its illustrative embodiment, the invention provides a heat recovery device adapted to be interposed as a unit in a flue duct to absorb heat from the hot gases and products of combustion escaping through the flue duct, connections being provided for a positive, controlled flow of a heat absorbing liquid through the device. The device includes an inner flue section, a liquid flow coil around the flue section and an outer sleeve relatively insulated from heated components and joining the parts into a device capable of being stored, handled and installed as a unit.

Abstract: A compact and maintenance-free means and method of regenerating the sensible heat from flue gases of fossil fuel furnaces by heat exchange through two circular layers of rock beds rotating under two semi-circular mantles with the first mantle applying hot flue gases to the beds and the second withdrawing preheated ambient air needed for combustion by said furnaces. When used for power plant flue gas treatment, layers of acid-resistant pipes containing boiler feedwater are sandwiched between the two rock bed layers to usefully recover the heat units arising from moisture condensation. The enormous water of condensation collects flyash and sulphur dioxide thus removing these pollutants from the stack gases. The heavy rock beds rotate slowly beneath the fixed mantles in a circular, pan-shaped, steel vessel floating on and cooled by a circular pond of water. Friction of rotation is minimal and gas leakage principally prevented by liquid seals. When flue gas temperature rises, as above 600 degrees F.

Abstract: An improved method and apparatus for heating fluids wherein separate gas streams of natural gas and air are compressed to a preselected pressure, passed to an injection and mixing zone for thorough mixing including expansion of one gas and compression of the other, passed to a combustion chamber for burning with the combustion products being further contracted and passed to a heat exchanger conduit where such combustion products are progressively further contracted as they are brought into heat exchange with the fluid to be heated.

Abstract: A calorific value boiler device for supplying heat to at least one user of heat contained in a heat medium via a first supply line and at least one return line. The device includes a boiler having a blower equipped burner with flue gases discharged in a specific direction and at least two heat exchangers arranged in series to receive the flue gases sequentially in that direction. Also provided is a stratified thermal storage unit for delivering medium to the user via a first supply line. A first line is for transferring heat medium from the first heat exchanger in the series to the top layer of the storage unit. A second line is for transferring heat medium from the bottom layer of the storage unit to the last heat exchanger in the series. A third line is for transferring heat medium from the middle of the storage unit to the first heat exchanger and having a flow cross section at least twice that of the second line.

Abstract: An improved method and apparatus for recovery of waste heat of the type having a first heat exchanger which transfers heat to a working fluid and a second heat exchanger which transfers heat from the working fluid is disclosed. The improvement comprises the provision of at least one storage tank for the working fluid having a volume calculated by the flow rate of the working fluid multiplied by a time difference between the time in which the combusiton chamber has its peak fuel requirement and a next subsequent time at which a maximum amount of waste heat is available to the combustion chamber. This minimum capacity can be obtained by the provision of one tank or several tanks having a combined storage capacity which meets or exceeds the calculated volume. Preferably the storage tank, or combination of storage tanks, is positioned between the heat exchangers so as to receive heated working fluid from the first heat exchanger and provide heated working fluid to the second heat exchanger.

Abstract: Normally wasted heat from the pilot burner and flue of a fuel fired hot water heater is used to preheat the water supplied to the main tank. An auxilliary storage tank receives incoming cold water. Water from the storage tank circulates through a conduit loop which extends in a spiral pattern through the flue and also through a special heat exchanger which concentrates heat generated by the pilot burner. The water that is preheated in the conduit loop is returned to the storage tank for storage until required by the main tank, at which time the preheated water is delivered to the main tank through a transfer conduit. Alternative embodiments are arranged to effect automatic flushing of the conduit loop when hot water is withdrawn from the main tank.

Abstract: Space heating and cooling and potable water heating are provided by a single appliance. The housing appliance is divided into four sections: a lower water storage section, a middle hardware section, an upper internal air handling section and a side external air handling section which may protrude through a building wall. A heating medium from a single burner heat exchanger may be directed to either a liquid to air heat exchanger for space heating or to a hot water storage tank for heating potable water. The storage tank contains a heat exchanger for heat transfer from the heating medium to the potable water. A single thermostatic flow control maintains a constant temperature of heating medium directed to either the liquid to air heat exchanger or the storage tank to provide condensation of products of combustion during the space heating mode of operation and part of the water heating mode of operation and yet preclude overheating of the heating medium.

Abstract: A high efficiency forced draft water and space heater maintains a desired air to fuel ratio and efficiency in combustion regardless of changes in air inlet pressure. The heater uses a venturi type proportioner and associated fuel regulator to provide an air and fuel mixture of constant ratio which is drawn from the proportioner by a blower and introduced into a closed combustion chamber for efficient burning and heating of a surrounding body of water.

Abstract: An apparatus for heating water, especially a hot-water boiler. The apparatus has a combustion chamber and two or more heat exchangers that are disposed one above the other. The heat exchanger disposed in the bottom of the apparatus is associated with a condensation chamber. In order to be able to operate this heat exchanger without water, and to be able to raise the efficiency of the apparatus as a whole, the heat exchanger of the condensation chamber is provided with a fresh air inlet and a fresh air outlet. Air is conveyed through this heat exchanger, whereupon it is heated up. This warmed air is supplied to the burner of the apparatus.

Abstract: A system wherein the contaminated cuttings are fed into the system for eventual incineration. The principal apparatus of the system comprises a plurality, preferrably three, of horizontally disposed cylindrical drying chambers mounted onto a skid for receiving contaminated cuttings into each separate chamber. There is provided on the first end of the chambers a receiving bin or hopper, wherein the cuttings are received from the shakers or the like into the bin, and dropped into an opening in the first end of the three chambers. Each chamber is provided with a seperate variable motor controlled auger disposed substantially throughout the length of the chamber wherein rotation of the auger would move the cuttings along the length of the interior of the chamber. The second end of each chamber is provided with a lower exit chute for removal of the cuttings from the chamber as the auger has moved into position.

Abstract: An industrial oven, including the combination of a steam generating tank having a water inlet and a steam outlet; walls depending from said tank for defining a combustion chamber therebelow; a preheater associated with one of the said walls exteriorially of said combustion chamber and having a water inlet therein and a water outlet thereof; said preheater water outlet communicating with said tank water inlet; means for generating heat energy within said combustion chamber so as to preheat water within said preheater and generate steam from water within said tank; and means for controlling the introduction of water into said preheater and into said tank so as to minimize the drop of steam pressure in said tank during introduction of water into said tank.

Abstract: An apparatus for preheating an engine is disclosed. The apparatus comprises a liquid fuel burning heater, a coolant pump for circulating engine coolant through the heater, a fuel pump for delivering fuel to the heater, a blower for delivering air to the heater, and a control module for maximizing the output of the heater. The heater comprises a liquid fuel burner and a two stage heat exchanger--the first stage for transferring heat produced by the burner to clean air supplied by the blower, and the second stage for transferring heat from the clean air to the engine coolant. The heater also produces a clean hot air discharge for heating an engine compartment, battery compartment or operator's compartment.

Abstract: A preheater for a conventional gas-fired water heater having an outer container, an inner reservoir, water conduits in fluid communication with the reservoir and openings in the outer container allowing the through passage of hot exhaust flue gas from a conventional hot water tank to have an increased residence time with respect to the reservoir for efficient heat transfer of the hot flue gases. The heated water is fed from the preheater to the hot water tank on demand. The preheater is placed atop the hot water tank to receive the hot flue gases therefrom.

Abstract: This invention relates to a method and apparatus for controlling the burn of coal, or fuel to produce the desired output of heat ranging from under 10,000 BTU per hour to over 150,000 BTU per hour, and the collection of said heat. It depends on the sizing of the grate, firebox and combustion area to produce the desired burn, the vertical exhaust pipes and soot and ash traps for self-cleaning and storing waste, the automatic controls for self-maintenance, the air washing system for cleaning the exhaust air of pollutants, the water heating coils and tanks for storing the produced heat, the chimney insulated compartments with gravel for accelerating heat absorption, and its own chimney that makes it a self-contained unit that can be located for use inside or outside of most any selected existing house or building.

Abstract: Normally wasted heat from the pilot burner and flue of a fuel fired hot water heater is used to preheat the water supplied to the main tank. An auxilliary storage tank receives incoming cold water. Water from the storage tank circulates through a conduit loop which extends in a spiral pattern through the flue and also through a special heat exchanger which concentrates heat generated by the pilot burner. The water that is preheated in the conduit loop is returned to the storage tank for storage until required by the main tank, at which time the preheated water is delivered to the main tank through a transfer conduit. Alternative embodiments are arranged to effect automatic flushing of the conduit loop when hot water is withdrawn from the main tank.

Abstract: A water heater and distiller apparatus is provided in which condensing steam is the distilling portion of the apparatus giving up its latent heat to water which is being heated in the water heating portion of the apparatus. In a preferred embodiment, products of combustion which are used to boil water in the distiller boiler, are later passed in heat exchange relation with the water heating tank in the water heating portion of apparatus. It is believed that the present apparatus is both energy efficient and uncomplicated as compared to the prior art.

Abstract: A method of purifying flue gases from refuse incineration by cooling and of recovering heat energy as well as an arrangement for performing the method. According to the method the flue gases are cooled in three stages, with the most beneficial structural material with regard to the temperature range, process conditions, and economy being selected in each cooling stage among the materials glass, plastic or alloyed steel. The sizes of the various cooling surfaces are determined such, that the temperatures of the flue gases immediately before the last cooling stage lie closely above the water dew point. The arrangement disclosed by the invention comprises a first cooling member, a second cooling member connected thereto, and a third cooling member connected to the latter and having its outlet connected to a droplet separator which is followed by a flue gas fan which in turn is connected to a chimney.

Abstract: A hot-water-furnace supplemental heater (60) replaces a manifold (48) used with a normal hot-water-furnace (10) having multiple furnace heating tubes (22). The supplemental water heater has a housing with a false bottom (66) and a supplemental tube (67) extending between a false bottom opening and a top-wall opening of the housing. A sidewall (62) of the housing and the false bottom form a manifold cavity (72) which collects combustion materials exiting from top ends (52) of the furnace heating tubes and directs them into the supplemental heating tube for heating water in a supplemental water heater cavity (68) defined by the sidewall, the false bottom, a top wall (64) and the supplemental heating tube. In a system, the supplemental water heater is placed in series with a furnace water heater to preheat water passing into the furnace water heater.

Abstract: A compact continuous flow energy efficient gas fired water heater/boiler for use in residential, commercial and industrial buildings wherein cold water enters the heater and flows downward through an outer annulus and then rises up through an inner annulus around a central gas flue, and wherein combustion gas flows upward through the central flue and then downward through a set of heat-conductive tubes and finally upwardly through the middle annulus to the exit. Air flow blower provides draft. The burner is capable of burning gas at widely varying rates of gas flow and is regulated by a gas modulator valve approximately proportional to the rate of hot water usage and the force for the gas modulator is generated by an orifice type differential pressure generator in the inlet water pipe.

Abstract: A hot water heater for trailers or mobile homes and the like, wherein increased heat capacity is provided due to exposure to combustion gases over large heating surfaces and including the use of heating fans whereby the heated water is conducted to radiators with the maximum heating temperature. The arrangement also provides for an additional supply of hot air in the area to be heated thereby eliminating the cold zone in the center of the room.

Abstract: In a water heating system, vapor in the products of combustion gases is condensed in a secondary heat exchanger positioned in a housing with the primary heat exchanger and combustion chamber. The two heat exchangers are coaxial coils with the secondary coil positioned below the primary. Gases flow radially through the primary coil and then axially through the secondary coil at an increased velocity. The gases are then used to pre-heat a gas/air mixture in a third heat exchanger within the secondary heat exchanger. The pre-heated gas/air mixture is burned in a burner within the primary heat exchanger and the gas products are drawn through the exchangers by a blower. A water storage tank is designed to enhance stratification of hot water over cooler water. The cooler water is used to condense vapor in the secondary heat exchanger.