Abstract: A clamshell heat exchanger (10) is provided for use in a heating apparatus including a burner for producing hot combustion gas. The heat exchanger (10) defines a multi-pass flow passage (11) for the combustion gas and includes a first plate member (30) and a second plate member (32). The first plate member (30) has a first series of parallel ridges (36) and valleys (38a-b), with at least one of the valleys (38a) being deeper than other of the valleys (38b). The second plate member (32) faces the first plate member (30) and includes a second series of ridges (36) and valleys (38a-b) that are parallel to the first series of ridges (36) and valleys (38a-b), with at least one of the valleys (38a) of the second series being deeper than other of the valleys (38b) of the second series. A first pass (14, 16) of the multi-pass flow passage (11) is defined by a number N1 of the ridges (36) and valleys (38a-b) of the first and second series.

Abstract: A heat exchange device for harnessing heat from an exhaust vent is provided including a furnace having a main inlet for receiving cooled air suctioned from a living area, a heating mechanism for heating the cooled air suctioned from the living area, a main outlet for delivering air to the living area which is heated by the heating mechanism, and an exhaust vent coupled to the furnace for expelling air associated with the generation of heat by the heat mechanism with such expelled air not being fit for channeling to the living air via the outlet. Next provided is a housing which divides the exhaust vent into a lower portion and an upper portion. The housing has an auxiliary inlet in communication with the living area for receiving the cooled air therefrom and an auxiliary outlet in communication with the living area for expelling air thereto. Lastly, a heat transfer mechanism includes a pipe formed in the shape of a helix.

Abstract: A secondary heat exchanger suitable for use in a condensing furnace which is in the form of a bank of a plurality of metal tubes which are positioned in a plurality of stacked rows. The tubes are interconnected to form a continuous fluid flow path and have a uniform adherent corrosion resistant polymeric internal surface. The tubes further contain a longitudinal seam which is formed by crimping the edges of the tube together to provide for the compression of two polymer surfaces together thereby forming a seal capable of maintaining its integrity at conventional design pressures.

Abstract: A heater for heating a stream of air has a burner assembly to heat the stream as it flows along a flow path and a primary heat assembly positioned in the flow path and coupled to the burner assembly for conducting gaseous combustion products. The primary heat exchange assembly has an array of U-shaped heat exchange tubes for conducting hot combustion products generated by the burner assembly to an array of second U-shaped heat exchange tubes for combustion products discharged from the first heat exchange tubes, the second tube having a smaller diameter than the first and being positioned in the space defined by the array of first U-shaped heat exchange tubes. Combustion products leaving the primary heat exchange assembly are passed through a secondary heat exchange assembly before being exhausted.

Abstract: A heat exchanger manifold (44) is provided which includes a plurality of manifold inlet openings (58) including sealant means such as grommet means (62) which receive the tube outlets (40c) of the condensing section (34) of a heat exchanger (28). The heat exchanger manifold (44) is made of a corrosion-resistant material such as a polymer such as one sold under the trademark LEXAN.TM. and the grommets (62) are preferably made of a resilient, corrosionresistant polymer such as rubber, e.g., a nitrile rubber. The condensing tubes (38a, 38b, 38c) are slanted to facilitate drainage of the condensate into the heat exchanger manifold (44) and a flue gas outlet (64) and a condensate drain (49) are provided to discharge, respectively, flue gas and condensate from the heat exchanger manifold (44). The condensing tubes (38a, 38b, 38c) are connected to the primary heating section (30) of the heat exchanger (28) through swaged joints (37).

Abstract: An unvented patio fireplace comprises a fireplace housing that has a front panel configured like an in room fireplace, and which fireplace housing is mounted onto a pedestal and base support for movement along a surface. The base support includes wheels and casters as desired for providing mobility. The base also supports a self contained fuel supply for supplying gas to a burner in the fireplace housing. Burner controls include an oxygen depletion sensor so that the unit can be unvented, and tilt sensors that will sense when the fireplace is tilted a selected amount to shut off the gas supply.

Abstract: A heat exchanger for use as a condensing heat exchanger in a gas-fired hot air furnace has a ceramic pipe forming an initial portion of a fluid flow path through the heat exchanger. The ceramic pipe receives the combustion gases from a primary heat exchanger and reduces the temperature of the combustion gases to below a certain temperature. A polymer-based structure is connected to the ceramic pipe and forms the remaining portion of the fluid flow path through the heat exchanger. The geometry and orientation of the ceramic pipe is selected so that the certain temperature of the combustion gases exiting the ceramic pipe is less than the softening temperature of the polymer-based structure. The resultant heat exchanger combines the high temperature and corrosion resistance of ceramic materials with the low cost and high corrosion resistance of polymer materials.

Abstract: A compact, non-polluting, extremely energy-efficient, through-the-wall vented forced hot air heater, which humidifies and cleans said hot air without any additional equipment or water supply, comprises a rotating cylindrical heat and moisture transport/storage element which has many substantially identical axially parallel flow passages and very large transfer surface per mass, a means for controllably transferring the heat and the moisture from the combustion products to said rotating element and then to said hot air stream counter-currently, and a means for preventing formation of air pollutants.

Abstract: A multi oil furnace is disclosed wherein the external cabinet shell houses a central burner chamber, an upper bank of conduits and a lower bank of conduits. Headers operably coupling the burner chamber, the upper and lower banks of conduits and a discharge opening define a flow path for the combustion gases created by the ignition of the used oil within the burner chamber. A ventilation chamber positioned between forward and rearward headers allows the passage of ambient ventilation air around the conduits and the burner chamber to effect a transfer of heat from the exhaust gases to the ventilation air while maintaining isolation therebetween.

Abstract: Air heater comprising a gas burner and heat exchange means including at least one heat-exchange wall which separates a first passage for flow of air to be heated from a second passage for flow of the flue gases produced by the burner, the air to be heated being made to flow by blower means through the first passage, the hot flue gases flowing in counter current through the second passage, wherein the burner is of the radiation type, and the heat-exchange wall comprises a convective-exchange part and an absorption part for absorbing the radiation from the burner, the flue gases heating the air by convection mainly in the region of the convective-exchange part, the radiation from the burner being mainly emitted towards the absorption part, the air flowing over this absorption part after it has flowed over the convective-exchange part.

Abstract: A connecting structure of a blast furnace hot stove of the type in which a heat accumulation chamber dome and a combustion chamber dome are directly connected to each other through a dome connecting pipe which does not have any expansion joint. The ratio (RD/TD) of the diameter (RD) of the dome connecting pipe to the diameter (TD) of the heat accumulation chamber dome approximately meets the condition wherein 0.24.ltoreq.(RD/TD).ltoreq.0.60, while the ratio (RD/ND) of the diameter (RD) of the dome connecting pipe to the diameter (ND) of the combustion chamber dome approximately meets the condition wherein 0.44.ltoreq.(RD/ND).ltoreq.0.80. The connecting structure may have a reinforcement ring provided on straight barrel portions immediately under the heat accumulation chamber dome and the combustion chamber dome, and a connecting beam may be fixed at one end to one of the reinforcement rings and engage at its other end with the other of the reinforcement rings for limited sliding motion.

Abstract: A furnace apparatus which includes a plurality of water walls. Each includes a plurality of tubes and the water walls collectively enclose a combustion chamber. The apparatus includes a plurality of windboxes, each of the windboxes is disposed intermediate adjacent water walls. A pulverizer and ducting to direct the flow of pulverized coal to the windboxes is also a part of the apparatus in accordance with the invention as is a bisector regenerative air heater having a rotor a housing having a generally cylindrical cavity in which a drum shaped rotor having heat transfer surfaces thereon is mounted for rotation on a shaft. The heater includes ducting for directing flue gas and forced draft air respectively into first and second angular sectors of the cavity which at any one instant will flow over respective angular sectors of the rotor. The rotor is heated during the travel of any portion thereof in the first angular sector and is cooled in the second angular sector.

Abstract: A forced air furnace has its blower mounted on a blower shelf beneath the heat exchanger, by screws that enter aligned clearance holes in the blower mounting flanges and blower shelf and which engage gripper holes in a bottom lip of the vertical cell panel that serves as the proximal wall of the furnace heat exchanger cell. This provides vertical support for the blower and absorbs stresses from up-and-down motion.

Abstract: The present invention involves a gas furnace having a condensate trap formed in the transition box between the secondary heat exchanger and the exhaust blower. The gas furnace includes gas burners which burn fuel within the passageways of the heat exchanger are induced through its internal passageways by an exhaust blower. The transition box connects the heat exchangers with the exhaust blower and provides a location for condensate to collect for discharge through the integral condensate trap assembly. Also, the exhaust blower housing has drainage ports to convey condensate from the blower and vent back to the condensate trap.

Abstract: A single forced air furnace (10) may be installed in any of an upflow, downflow, or horizontal airflow orientation, with discharge of flue gases either opposite to or concurrent with the primary airflow path. The combination of design features which provides this versatility includes the following features: an inducer assembly (24) for withdrawing flue gas from the furnace heat exchanger (20), which inducer assembly (24) may be positioned to direct the discharge of flue gas in a selected one of a plurality of directions; an optional internal flue duct (64) for directing the flue gas through the furnace vestibule chamber then through the furnace housing (12); and the fact that the furnace housing (12) is dimensioned and configured so that the furnace may be supported on any one of four different sides (O, I, S.sub.1, S.sub.2) of the furnace housing (12).

Abstract: A furnace includes at least one heat exchanger with first and second plate members secured together to define passageways that form serpentine flow paths between an inlet passageway and an outlet passageway. The inlet passageway receives hot products of combustion from a burner which extends into it. A blower induces the flow of the combustion products through the heat exchanger. A second blower induces the flow of air over the surfaces of the exchanger.

Abstract: An inducer (40) for causing a flow of combustion air into and gases of combustion through and out of a furnace (10) of the condensing type. The inducer is intended for use, without modification of its design or size, in a series of furnaces of the same basic design but having different heating capacities and therefore different requirements for flow through the induction flow path. The furnace design is such that a given furnace is capable of operation so as to provide a flow of air to be heated that is either up, down or horizontal with only minor field modification on installation. The inducer has two discharges (43), only one of which is used in a given installation. The other discharge is blocked with a plug (61) of special configuration that can vary the output of the inducer to ensure optimum flow of combustion air into and gases of combustion through and out of the furnace.

Abstract: Poor heat exchange in a heat exchanger between a flue gas passing through the heat exchanger and air being forced through the heat exchanger can be improved in a heat exchanger and combustor (30) for exchanging heat between a forced air stream and a flue gas generated by a plurality of spaced, parallel burners (44) with a construction including spaced, upper and lower headers (32, 34), a plurality of tubes (50), one for each burner (44) extending in parallel between and mounted to the headers (32, 34). Each tube 50 has a first section (56) of enlarged cross section adapted to serve as a combustor for fuel to generate the flue gas and a narrowed, second section (70) for exchanging heat between the flue gas and the forced air stream. Each second section includes generally flat, parallel spaced walls (58, 60) with each of the walls (58, 60) having dimples (74) therein which are directed toward the other of the walls (58, 60) into substantially contacting or almost contacting relationship therewith.

Abstract: A bracket for a hot surface ignitor is provided with a central opening having downwardly directed supporting arms and upwardly directed L-shaped retention arms such that the ignitor can be lockingly engaged with the bracket without creating crack-inducing stresses in the ceramic base of the ignitor. The bracket is further provided with upwardly directed resilient detents that allow the bracket to be securely snapped into the burner box of a gas furnace. The bracket thus positions the hot surface portion of the ignitor within the burner box while positioning the ceramic base and electric supply wires exterior to the box.

Abstract: An afterburner positionable adjacent the discharge end of a combustion chamber of a fuel-burning heater utilizes a ring portion and a nose cone portion which are constructed as a unit out of a single piece of material. The ring portion accommodates the attachment of the afterburner adjacent the discharge end of the combustion chamber, and the nose cone portion has a skirt including peripheral edge portions which are spaced from and overlap the inner edge portions of the ring portion so that the direction of movement of the flow of products of combustion through the combustion chamber is altered before the combustion products exit the chamber. The afterburner is formed from a single piece of sheet steel in steps involving a first press operation, a lancing operation, and then a second press operation.

Abstract: An improved heating system is disclosed for providing heated air to a heated space, preferably using a gaseous fuel as the energy source. The system preferably includes an air heating sub-system, a compact combustion chamber, a separate cold air supply sub-system for conveying cold air from the heated space to the air heating sub-system, a combustion chamber heat exchanger in fluid communication with the cold air supply sub-system for transferring heat thereto, and a separate air circulating sub-system for withdrawing cold circulating air from the heated space. A mixing chamber is provided for mixing heated air from the air heating sub-system with the cold circulating air to provide heated air to the space. The system also preferably includes separate sub-systems for supplying pressurized combustion air and pressurized gaseous fuel to the air heating sub-system and for forcibly conveying exhaust gases therefrom without the need for a draft-type chimney or stack.

Abstract: A heating and air conditioning unit has a fan compartment containing a hammock-type filter. The hammock-type filter rests upon feet elevated above the bottom of the fan compartment so that air may flow into the fan through either the bottom panel of the hammock filter or either of the side panels. The front and back of channels of the bottom pannel are telescoped so that they can be expanded and always be longer than the width of the fan. Sponge rubber is provided at the front and back so that if a larger compartment is used that air leakage at the front and back is prevented by the sponge or foam rubber. The top edges of the side panels rest against the sides of the fan compartment. Foam rubber along these edges prevents noise caused by vibration as well as preventing air leakage.

Abstract: Means and method to reconstruct the terminal end of the fluid line adjacent the pump of an oil furnace to provide a coupling that may be opened to receive the delivery end of a pressure fluid gun to substantially eliminate oil seepage and the necessity of twice closing and reopening the normally open valve adjacent the reservoir.

Abstract: The improved inshot burner cluster apparatus of the present invention functions to provide combustion of a gaseous fuel and air mixture which is injected through an aperture in the inlet plate into the combustion compartment of a heat exchanger, and includes a burner cluster which may have a selected multiplicity of burners formed from an interjoined upper half shell and a lower half shell. The modular, and essentially clam-shell, form of construction allows for ease of forming the burner elements by embossing the sheet metal half shells, for example using a progressive type of punch press die which can thereafter cut-off any number of burners to form a burner cluster.

Abstract: The present invention relates to a unitary heat exchanger for an air conditioner which is capable of minimizing the size, weight, and the power consumption thereof, and improving the thermal efficiency. The unitary heat exchanger comprises an air intake member for introducing the room air, and a combustion furnace for firing a fuel with the air introduced through the air intake member to generate a hot combustion gas. A heat exchanger is disposed in line with the furnace for passing the hot combustion gas from the combustion furnace therethrough and heating fresh room air supplied by a blower. An air exhaust member discharges the hot combustion gas from the heat exchange means.

Abstract: Basically the present invention in it's most simple form or embodiment is directed to a controlled labyrinth heat exchanging oil nozzle assembly for use as a flame producing nozzle within an oil burning heating system, particularly adapted to burning of waste oil. The nozzle assembly comprises a block, the temperature of which is controlled or controllable and in which there is at least one cylindrical bore (preferably two bores are provided) into which director plugs are specially inserted. The block, the bore or bores and the flow director plug or plugs are designed to provide a fuel flow passage which undulates upward and downward thereby increases the dwell time or the time during which fuel is within the block and also creating substantial surface area through which heat is transferred or transferable from the block when it is heated to the fuel flowing in such an undulating manner therethrough.

Abstract: A direct contact condensing heat-exchanger is provided with a water heat transfer medium in which combustion product gases are dispersed in finely divided bubble form against a relatively low hydrostatic pressure differential for efficient sensible heat and latent heat recovery purposes. In one actual application, a warm-air furnace system having a burner that produces combustion product gases as a heat source is provided with the novel direct contact condensing heat-exchanger as a seondary heat-exchanger that advantageously recovers both sensible heat and latent heat from the combustion product gases.

Abstract: The present invention is an enhanced tubular heat exchanger for a furnace. The tubes of the heat exchanger include an enhanced portion which has a smaller cross-sectional area than the flue portion, in the form of an elliptically shaped tube. The enhanced portion further includes turbulators to promote the heat exchange from the heated flue gases. Circulation of air around the exterior of the tubes is also facilitated because the enhanced portion is disposed at a small angle relative to the flue portion. A plurality of tubes are disposed within the heat exchanger so that the circulation air first flows over the enhanced portions then over and around the generally cylindrical portions. This lowers the initial pressure drop in the circulation air flow and thereby facilitates the circulation of and heat transfer to the air being heated.

Abstract: A fuel burning furnace includes a number of energy efficient features. The furnace includes a heat exchanger in which combustion air is preheated by hot discharge gases. Diverters are provided in the heat exchanger to continually urge hot combustion gases toward the interior portions of the heat exchanger to improve its heat transfer characteristics. The furnace incorporates a number of features to determine malfunction and indicate inefficient operation. A humidification control system for the humidification or dehumidification of circulated air also is provided. The furnace also includes a blower motor system which compensates for loss of tension in driving belts and makes correction for blower speed in response to temperature variations.

Abstract: A hot-air furnace has a long-flame burner for combusting gas or liquid fuel with a combustion chamber connected to the burner and having its length (l) and width (w.sub.1) in relationship of w.sub.1 <l. A heat exchanger is located above the combustion chamber and has internally a gas flow guide plate which guides combustion gas flow discharged from the combustion chamber to the heat exchanger. The heat exchanger has a width (w.sub.2) and length (l) in the relationship of w.sub.2 <l. An exhaust port for exhausting the combustion gas flow is located at the front or rear of, right or left-hand side of or on the top side above said heat exchanger. A casing has a drum integrally connecting the combustion chamber and the heat exchanger, an air flow guide and directing plate which covers the drum, a radiant heat absorber plate outside the combustion chamber, and a blower above or below the drum.

Abstract: A serpentine passage for a gas furnace clam shell-type heat exchanger comprising a serpentine passage having an inlet and an outlet where the serpentine passage, from the outlet toward the inlet, is shaped as a leaning, cursive w with the trailing end curling downwardly and underlining the w.

Abstract: In a firing plant which is operated with fossil fuels, the exhaust gases (A) from the combustion space (22) are cooled in a heat exchanger (X). A part of these cooled exhaust gases (A') are mixed with fresh air (L) and are conducted by means of a fan (D) in the direction of the burner (Z). This exhaust gas/fresh air mixture forms the combustion air (15) for the burner (Z). Before the introduction of this combustion air (15) into the burner (Z), it is again heated in the heat exchanger (X'). The combustion air (15) preheated in this way ensures complete evaporation of a liquid fuel (12) and acts against the high flame temperature peaks in the combustion space (22) immediately after the burner (Z), which are responsible for the formation of NO.sub.x. The burner (Z) can be operated with liquid and/or gaseous fuel.

Abstract: A burner control for a condensing furnace having a flame proving circuit that incorporates the flame at the burner to be closed and that opens upon absence of a flame to cause a gas valve to close and block the flow of gas to the burner. A short circuit shunting the flame proving circuit includes a probe that projects into the outlet manifold of the condensing furnace. If liquid level in the outlet manifold reaches the probe, a short circuit is closed between the probe and a ground on the manifold. The control to the valve is energized to close the valve in the same manner as if the flame had extinguished at the burner. Upon closing the gas valve, the burner is extinguished.

Abstract: A carbon desorption heater (10) for use in a system for removing volatile organic contaminants from a carbon filter is disclosed as having a housing (30) in which a recirculating heating circuit (36) is provided with a recirculation blower (44) that moves the air past a burner (50) for flow through a first flow path (60) of a heat exchanger (58) with a portion of the recirculated air exhausted during each cycle of flow through an exhaust stack outlet (52). A delivery blower (64) within the housing (30) moves air through a second flow path (62) of the heat exchanger (58) for heating prior to delivery to a supply outlet (34). The heater includes a plurality of modules (90) that are sufficiently small so as to be shippable and subsequently securable to each other at the factory site where the heater is to be used.

Abstract: A heating and ventilation unit has a ceramic heat wheel rotatable within a housing between first and second plenums through which fresh and stale air, respectively, are forced to pass in a hot air ventilation system. The heat wheel is made of cordierite material such as is used in catalytic conversion systems for automobiles. It is formed with non-communicating and axially-extending parallel pores having a pore density of 62 pores per sq. cm. As it rotates the heat wheel transfers to the fresh air both the heat generated by a gas burner in the second plenum, and also low grate heat contained in the stale air. The burner is housed within a combustion housing by means of which the combustion gases are confined to a generally D-shaped area of the heat wheel.

Abstract: In a gas furnace designed for operation with natural gas, the use of propane as a fuel is facilitated by increasing the inducer speed by a factor which is obtained by comparing the higher inducer speed necessary to bring down the heat exchanger temperature to an acceptable level, with the original lower inducer speed that had caused the temperature to exceed the allowed limit. Provision is made for electronically applying the multiplying factor by simply operating a gas selector switch.

Abstract: A pulse combustion fired space heater is disclosed. The heater has an exterior cabinet enclosing an interior housing having a pulse combustion burner mounted therein. The burner includes a plurality of generally flat elements which cooperate with the interior housing to provide a tortuous path for air circulated through the chamber during heat transfer. The circulating air pressurizes the interior housing to enhance uniformity of heat transfer and suppress structural vibrations.

Abstract: A filter support base for use with an upflow forced air furnace is disclosed. A rectangular base defining a return air plenum is adapted for floor mounting support of the furnace and includes a pass-through opening in communication with the intake opening of the furnace plenum. A filter base provides a rectangular enclosure that is secured intervening between the base and the supported furnace. Within the filter box there are elongated channel members extending about the internal perimeter in planar alignment with a filter access opening for support of a received filter element in the return air stream. A cover, hinge supported above the opening, is displaceable for covering the opening during normal furnace operation and for exposing the opening when filter access is desired.

Abstract: The elbow between the discharge end of the draft inducer and a horizontal vent pipe is provided with a well structure on the lower side of its discharge end such that condensate forming in the vent pipe is prevented from passing through the elbow into the draft inducer housing. The well structure, in addition to restraining the flow of the condensate, provides for the draining off thereof, and presents a minimal restriction to the flow of flue gases flowing to the elbow. Provision is also made for maintaining a tight seal between a rectangularly shaped inlet lip of the elbow and a rectangularly shaped discharge end of the inducer housing by making the inlet lip of varying thicknesses, with the lip being thinnest at its corners and thickest at its side midpoints.

Abstract: The present invention pertains to a condensate trap for a condensing furnace comprising a housing having an inlet adapted to be connected to a condensing heat exchanger, an outlet for flue gas and an outlet for condensate. The housing has a chamber therein, a valve seat defining an opening from the chamber, a float valve in the chamber adapted to close the opening, and a drain orifice in the outlet for condensate forming a dam to prevent negative pressure from undesirably dislodging the float valve from the opening. The drain orifice is constructed and arranged to retain condensate at a level higher than that of the bottom of the valve seat.

Abstract: A filter support base for use with an upflow forced air furnace is disclosed. A rectangular base defining a return air plenum is adapted for floor mounting support of the furnace and includes a pass-through opening in communication with the intake opening of the furnace plenum. A filter base provides a rectangular enclosure that is secured intervening between the base and the supported furnace. Within the filter box there are elongated channel members extending about the internal perimeter in planar alignment with a filter access opening for support of a received filter element in the return air stream. A cover, hinge supported above the opening, is displaceable for covering the opening during normal furnace operation and for exposing the opening when filter access is desired.

Abstract: A warm air furnace system comprising a closed casing having an air inlet and an air outlet duct, a fan to draw air from the air inlet toward the air outlet duct, a water tank mounted into the warm air furnace casing, a radiator anchored to the warm air furnace casing in proximate register with its air inlet and connected to the water tank by a water intake line and by a water outlet line. A heating element is immersed in the water tank, to heat up to a first threshold temperature the water. A pump recirculates the water from the tank to the radiator and back. A water vapor by-pass tube interconnects the water tank to the air outlet duct, so as to humidify the air warmed by the radiator.

Abstract: This invention provides improved gas-fired heater means for supplying heat to a space, such as a room, house, building, vehicle, or the like.

Abstract: The heat exchanger of a gravity flow wall furnace defines a tortuous, mostly vertical path for the combustion gases to improve heat transfer to the room. The gases are directed upwardly in a combustion chamber and then split into two portions and conducted through two radiators having paths which extend downwardly adjacent to but spaced from the chamber and then upwardly again leading to a flue. The chamber and the radiators are oriented edgewise with respect to the wall so that all can fit within the space between a pair of studdings in a conventional stud wall.

Abstract: A compact, high efficiency condensing furnace includes a combustion chamber and a pair of radiators. The temperature of the combustion gases is reduced in one of the radiators to the point at which combustion products condense, thereby extracting the latent heat of vaporization from these combustion products. Each of the radiators has an inlet and an outlet and a baffle between the inlet and outlet to prevent combustion gases from passing directly from the inlet to the outlet. Additional turbulence-providing baffles can be provided within the radiators if desired. A combustion air inlet pipe extends through a recess in the bottom of each radiator to the combustion chamber, and a gas burner tube extends generally concentrically within the combustion air inlet pipe to provide a gas flame within the combustion chamber. A flame spreader plate directs the flame toward the bottom of the combustion chamber.

Abstract: A draft-assisting chamber is positioned between the combustion chamber and the flue pipe of a heating appliance so as to capture combustion gases in a quantity sufficient to initiate gas flow through the flue pipe. By use of the chamber, gas flow is initiated in the flue pipe during conditions that would otherwise delay such initialization.

Abstract: A heat exchanger unit having opposed pan shaped sections with perimeter flanges which are folded one over the other to secure the sections together. The section having the inner flange is formed with a displaced flange portion or bead all along the perimeter flange portions, which bead is elastically displaced by the folded over flange to form a substantially leakproof joint.

Abstract: A method and a system for providing thermal power to an electrical power plant wherein substantially whole trees are supplied as fuel without being processed into small woodchips or chunks. The substantially whole trees stored in the drying building to lower their moisture content, and thereafter are transported to a charge pit located adjacent to a combustion chamber. The substantially whole trees are fed into the combustion chamber by a ram feeder and burned therein. The heat created by the combustion is absorbed by a boiler section and in the form of steam it is supplied to a conventional electrical power generator.

Abstract: A safety device for monitoring the condition of the condensate outlet conduit in a high efficiency furnace is provided which comprises a float member positioned in a condensate trap arranged to float on the condensate and to rise in response to a rising level of condensate in the trap to block the gas vent inlet. A pressure sensing device is utilized to sense the back pressure in the vent and when the float blocks the vent inlet, the back pressure increased and the sensing device will then operate to terminate operation of the furnace.

Abstract: A forced hot air furnace having a continuously wet recuperative heat exchanger. The recuperative heat exchanger is positioned in the hot air chamber at an upward incline from the firebox to the outside flue. Inclined positioning enables heat exchanger condensate to drain counter to combustion products. Condensate is collected in a reservoir located in the firebox. Combustion products flow over the reservoir thereby becoming elevated in dew point before entering the heat exchanger. Consequently, the amount of condensation formed in the heat exchanger is substantially increased over conventional heat exchangers. Condensate will form along the entire length of the heat exchanger resulting in all wet operation. In another embodiment, continuously wet operation is achieved without a water reservoir. In still another embodiment, the continuously wet recuperative heat exchanger is coupled to the output of a non-recuperative heat exchanger.