Abstract: A horizontal combined air intake and combustion gas vent terminal assembly is provided having improved wind pressure response and anti-recirculation characteristics. The terminal has a vent conduit disposed inside an air intake conduit. A scoop assembly is provided at the intake conduit inlet to increase the intake air pressure at the inlet. The vent conduit is nozzle-like to throttle combustion gases, thereby accelerating the gases and permitting the terminal to project the gases away from the intake conduit terminal. Vent conduit is disposed asymmetrically with intake conduit to further discourage mixing of intake air and combustion gases. The terminal may also be provided with a static pressure measuring means to provide an intrinsic safety shut down system within the terminal in case of blockage of the intake or vent by snow, ice or other debris.

Abstract: A horizontal combined air intake and combustion gas vent terminal assembly is provided having improved wind pressure response and anti-recirculation characteristics. The terminal has a vent conduit disposed inside an air intake conduit. A scoop assembly is provided at the intake conduit inlet to increase the intake air pressure at the inlet. The vent conduit is nozzle-like to throttle combustion gases, thereby accelerating the gases and permitting the terminal to project the gases away from the intake conduit terminal. Vent conduit is disposed asymmetrically with intake conduit to further discourage mixing of intake air and combustion gases. The terminal may also be provided with a static pressure measuring means to provide an intrinsic safety shut down system within the terminal in case of blockage of the intake or vent by snow, ice or other debris.

Abstract: A fireplace downdraft regulator having a first end and a second end, such regulator extending across the top of a fireplace opening, such regulator having an aerodynamic draft header portion having a front face and a height and length, such draft header portion extending downwardly and rearwardly from the fireplace top at approximately 45 degrees to a vertical to form a corner angle and then extending upwards at approximately 90 degrees to the aerodynamic draft header portion to form a deflector portion with the deflector portion angled upwards into the chimney such that the inside portion of the regulator deflects downdrafts back upwards within the chimney and the aerodynamic draft header portion aids in drawing air from the room, which air travels down its front face and around the corner angle and back up the outside face of the deflector portion to help increase the updraft of air within the chimney.

Abstract: A vent damper is provided for limiting the flow of ambient air through the central core of a hot water heater having a combustion chamber, the central core forming an exhaust port leading to an exhaust duct for evacuation of exhaust gases from the combustion chamber. The vent damper includes an annular base having an upwardly facing opening forming a passageway therethrough for passage of the exhaust gases from the exhaust port to the exhaust duct. A poppet is pivotally supported above the annular base means to pivot between a closed position closing the passageway and a open position opening the passageway. The poppet is configured such that the exhaust gases generated in the combustion chamber and passing out of the exhaust port cause the poppet to pivot into the open position such that the gases may flow through the passageway.

Abstract: An integral vent damper/hood apparatus for regulating draft in a flue of a hot water heater includes a damper support having a hemispherical dome, a congruent cylindrical portion with a plurality of openings therein for passage of flue gas therethrough, and a bottom support. A coaxial faceted guide is disposed between the hemispherical dome and the bottom support with a flue gas floatable damper disposed between the hemispherical dome and the bottom support and moveable along the coaxial faceted guide in response to flue gas exiting the hot water heater flue. The damper includes a coaxial circular aperture therein for enabling the movement of the damper along the faceted guide with contact occurring only at intersections of the guide facets. A hood is provided for conducting flue gas passing through said damper support into an exhaust flue along with a fixture for coaxially attaching the hood and damper support to the hot water heater flue.

Abstract: A fireplace, comprising an inner jacket and an outer jacket defining an air circulation path therebetween, is provided with a smoke chamber convection wall and a baffle convection wall oriented so as to efficiently transfer heat from the fire box to the air circulation path. A damper plate and a back draft blocking wall are positioned in the fireplace so as to effectively block back drafts in both the open and closed damper positions. The fireplace also includes exterior controls whereby the damper plate and an outside air vent can be controlled in a safe manner. A clean out shaft and a draft control are also provided to facilitate safe operation of the fireplace.

Abstract: A gas-fired, simulated log fireplace insert incorporating an automatic flue damper for controlling the operational state of a chimney vent (open/closed) in response to gas combustion, an externally mounted carbon monoxide detector for terminating or inhibiting gas combustion in response to an unsafe level of detected carbon monoxide and a temperature actuated switch, disposed within the firebox area of the fireplace proximate the flue, for terminating gas combustion in response to excessive fireplace temperatures caused by a malfunctioning damper.

Abstract: A simulated solid fuel effect gas fire comprising two elongate simulated solid fuel elements in the form of logs, with a partially aerated gas burner arranged in front of and below each log with respect to the front of the fire. Thus, in use, the flames from the burners engage a lower front portion of the logs, the flames then passing around the front of the logs. By this arrangement the lower front regions of the logs are heated to glow as radiants and the flames subsequently lick around the front of the logs as yellow flames, in accord with the visual effect of a real fire, complete combustion having been attained in the ambient atmosphere in front of the logs to thus form the yellow flames. By the provision of nodules by virtue of a bark pattern on the upper front portion of the logs, the flames heat the nodules to red heat and enhance both the radiant heat derived from the fire and the visual effect of the fire.

Abstract: A wall furnace is disclosed in which a secondary heat exchanger is provided to maximize the heat transfer efficiency of the furnace. The secondary heat exchanger faces the room to be heated but is aligned directly behind the primary heat exchanger. The length of the secondary heat exchanger is shortened as compared to the combined length of the combustion chamber and primary heat exchanger so as to reduce inefficiencies due to reheating of the combustion gases and to promote air flow and heat transfer around the secondary heat exchanger. Thus, this configuration provides for two essentially separate circulation circuits for heat transfer and maximum furnace efficiency. Separate heated air deflectors are also provided for each of these circuits. A side venting draft hood is also disclosed.

Abstract: A novel draft hood for mounting on top of a gas conversion unit to form an adaptor and coupler between the gas conversion unit and a chimney includes a box structure having a guide flange and a plurality of positioning flanges thereon. A down draft diverter is installed inside of the box structure juxtaposed the exhaust outlet in the top of the draft hood. A novel spring alignment means including control rod are inserted through the top of the draft hood and employed as a positioning and aligning device maneuverable from the inside of the combustion chamber of the gas conversion unit and employed to apply a spring force to the draft hood which couples it to the gas conversion unit.

Abstract: A fireplace has a manifold positioned between a combustion chamber and a flue. The manifold has a pair of inlets to supply dilution air to the flue, one extending from a front face of the fireplace, and the other from a rearward location. A baffle extends across the outlet of the manifold to prevent direct communication between the combustion chamber and flue. The inlet at the front face enables the flow of dilution air to be checked with the fireplace installed without having to accomodate the full flow of dilution air. The baffle prevents downdrafts from adversely affecting the combustion in the combustion chamber.

Abstract: A vent damper for limiting the flow of ambient air in a hot water heater including a main burner, a pilot light burner and a central core for evacuation of exhaust gases from the main burner and pilot light burner. The vent damper comprises an inner shell having legs that extend downwardly and attach to a central baffle which directs the flow stream of exhaust gases passing through the exhaust port, a closure element slidably engaged about the inner shell which is movable between an open position and a closed position, a deflector attached to the upper end of the inner shell for deflecting downdrafts and limiting the upward travel of the seal ring, and an outer shell attached to the deflector that houses the aforementioned components.

Abstract: A wind-resistant heating appliance has a housing with air inlet openings for sustaining combustion generating flue products inside that housing which also has an outlet for flue products. The heating appliance has a top structure above that outlet and the housing. A top wall of that top structure is penetrated with exhaust openings for flue products along opposite edges of that top structure. The outlet between the housing and the top structure is provided with a transverse outlet channel inside the top structure and has opposite ends open at the exhaust openings adjacent the opposite edges of the top structure. That transverse outlet channel is solidly enclosed along its top, sides and bottom between the opposite ends, except for the outlet between the housing and the top structure. The exhaustion of flue products in various wind conditions is further aided by increasing the speed of flue products passing through the outlet from the housing to the transverse outlet channel.

Abstract: A side wall termination unit for a gas boiler which terminates side by side vent and air supply pipes extending through a building side wall. The pipes extend through inside and outside plates on the internal and external wall surfaces. A one piece termination cap is mounted on the outside plate and includes a sleeve which holds the vent pipe in alignment with a vent opening in the cap. The intake end of the air supply pipe is butted against stops to keep it exposed. Extending around the sleeve and stops is a wall formed by spaced apart fingers which present between them air intake openings for allowing outside air to enter the intake pipe. A peripheral flange on the termination cap is spaced outwardly from the building wall to provide an air intake slot.

Abstract: A reverse flow prevention device for combustion apparatuses control operated by electrical power, and which is provided with a combustion gas discharge tube for discharging the combustion process by-product. The reverse flow device comprising a reverse flow gas collecting tube installed within the combustion gas discharge tube for collecting reverse flow gas. The reverse flow device also comprises a detection means, with a function of detecting a reverse flow gas and turning OFF the combustion apparatus when the pressure of the reverse flow gas acting on the detection means is above a certain level.

Abstract: An outdoor heating appliance includes a top structure having a top surface, a stationary airfoil, and exhaust openings for flue products. The operation of the heating appliance is rendered wind resistant by generating with the stationary airfoil, in a region above the top surface and in repsonse to wind, an air pressure lower than an air pressure of that wind, and by locating the exhaust openings in that region, whereby the flue products are exhausted from the outdoor heating appliance by the wind. An inlet opening may be provided below the top surface at the airfoil for receiving part of the wind, in order to sustain combustion and generate inside the heating appliance positive pressure toward the exhaust openings by guiding air from the received part of the wind through a channel to a burner in the heating appliance.

Abstract: An improved vent damper for oil or natural gas-fired hot water heaters includes a damper assembly incorporated into the exhaust duct above a hot water heater, and contains a lightweight, floating poppet closure slidably mounted on a reduced-diameter exhaust pipe. When the hot water heater's main burner is operating, hot exhaust gasses lift the floating poppet closure, and the gasses escape through the gap thereby created around its base. These exhaust gasses are then vented to the outside air via an exhaust duct. When the main burner is turned off again, the floating poppet closure falls back again to its original (closed) position, thereby blocking the exhaust duct and preventing cool room air from circulating through the heater and its central core. Pilot light exhaust gasses are able to continuously escape through the reduced-diameter exhaust pipe even when the floating poppet closure is in the closed position.

Abstract: A device for detecting the diversion of gas furnace or gas hot water heater exhaust into a dwelling due to chimney backdrafting detects a sustained rise in the temperature of the gases passing through the draft-diverter orifice. A significant rise in temperature indicates that the above condition has occurred. This temperature rise is recorded only after the condition has persisted for a sufficiently long period of time, thereby avoiding the recording of temporary backdrafting conditions which are not required to be recorded. The device consists of a high temperature resistant plastic strip or other material with similar conductivity and specific heat qualities with a temperature sensitive color-change material mounted on the surface of the plastic strip at one end of the strip. This strip is attached to the furnace or gas hot water heater in a preferred location with the color-change material facing away from the normal flow of backdrafting exhaust gases.

Abstract: A terminal unit for a balanced flue has an air inlet duct (10) and an outlet duct (20) projecting beyond the mouth of inlet duct. An elliptical plate (30) encloses a region around the outlet duct to inhibit combustion products for entering the inlet duct. Alternatively a circular plate (60) could be used.

Abstract: A vent system for a gas fired swimming pool heater is disclosed in which replacement of three components is all that is required to change the heater vent to one for use with outdoor installed heaters to one for use with indoor installed heaters. The parts replacement is sufficiently simple to enable unskilled purchasers of the system to effect the changeover.

Abstract: A flue control device for slowing the rate at which heated exhaust gases rise through an exhaust stack comprises a cylindrical housing enclosed by end caps, with an offset inlet and outlet being positioned in opposite end caps. The interior of the housing defines a baffle chamber, and a baffle mechanism is positioned in the baffle chamber between the inlet and outlet. The baffle mechanism comprises two overlapping plates, each plate having a prominent flange extending in an upstream direction relative to the flow of gases through the baffle chamber. The flanges interrupt and slow the swirling circular flow of gases as they pass through the baffle chamber. The baffle and housing are of a size such that the cross-sectional area of the restricted portion of the housing adjacent the baffle is at least as large as the cross-sectional area of the exhaust stack.

Abstract: A vent assembly adapted for venting into the atmosphere hot burner exhaust gases from the flue exhaust port of a heating appliance within an enclosure, such assembly including an exhaust duct and a relief duct. The exhaust duct is connected at one end to said flue exhaust port and is opened at its other end to the ambient atmosphere outside of the enclosure. A selectively responsive closure device, such as a thermally controlled damper, is disposed within the exhaust duct. The relief duct is connected to the exhaust duct at a point along the flow of exhaust gases upstream of the closure device and has a relief aperture disposed at a height between that of the exhaust port and that of the burner.

Abstract: Improved flue structure for domestic heating equipment such as a gas fired hot water heater. In conventional gas fired water heaters, the heater is directly connected to a chimney or the like by a single flue pipe and this results in a wasteful loss of heat and inefficient use of fuel. The invention provides a multiple, interconnected flue pipe arrangement whereby a substantial portion of the heat produced by the gas burner is trapped in the flue structure keeping it in the system longer and thereby materially cutting down on the heat loss. In one embodiment of the invention, a flue pipe from the heater is connected to the upper end of a second flue pipe that is closed at its top and a third flue pipe, concentrically mounted in the second flue pipe, conducts the heater flue gases to the chimney. Due to the arrangement of these pipes as will be described in detail hereinafter, heat is trapped at the upper end of the second flue pipe resulting in a substantial increase in efficiency.

Abstract: A flow control device is provided for use with a fan to prevent pressure excursions in a furnace or any other hardware equipment to which the fan is connected. The control device is connected in parallel relation with respect to the fan so that a recirculating flow path is formed between an outlet of the fan and an inlet thereof. This recirculating flow path controls the pressure differential produced by the fan. The control device includes duct work and a controlled element, preferably, a damper. In a furnace system, an induced draft fan is connected in series with a furnace and the controlled device is normally in a closed position in parallel with the induced draft fan. Upon the occurrence of one or more predetermined fault conditions, the controlled device modulates open to provide a circulating path through the induced draft fan and rapidly controls the pressure differential between the inlet and outlet of the fan.

Abstract: A venting system for the combustion chamber of an oil or gas-fired heating appliance has an elongate diverter box arranged vertically exteriorly of the heating appliance. Such diverter box has an upper end tightly closed off by an insulated imperforate cover and a relief open lower end closed for safety by a perforate grill in which a safety spill switch is mounted. The interior of the diverter box houses a vertically disposed centrally arranged insulated baffle having an upper end in fume tight engagement with cover and a lower free end terminating substantially above the grill. The baffle divides the box into a flue gas inlet section that is connected at the upper portion of the box to the appliance and a vent gas outlet section that is connected at the upper portion of the box to the chimney flue. The inlet section has a turning vane provided on the end wall just below the lower free end of the center baffle.

Abstract: A solid fuel burning stove (10) includes a firebox (11) having an insulated bottom chamber in which fuel is burned. The bottom chamber includes an insulated bottom surface (72) and walls (18, 20, 22, 24) which provides for heat retention when fuel is burned therein thereby creating high temperatures. The bottom chamber of the firebox (11) is divided from a top chamber by a horizontally extending baffle (46) which directs flow of exhaust gases from the bottom to the top of the firebox (11). The exhaust gases are burned in the top portion of the firebox (11) by means of the heat generated within the lower chamber and the introduction of fresh combustion air. This fresh combustion air is drawn in through an orificed pipe (49) extending along the length of the firebox.

Abstract: An energy conserving device for preventing loss of heat energy from a heater to a chimney by means of a fluid gas heat trap to choke off either chimney draft and/or heated convectional air currents lost to the chimney when the heater is OFF but allowing combustion gasses to vent freely to the chimney when such gasses are generated. The deivce also acts as a diverter for either up or down drafts from the chimney to direct them away from the heater. In another form when the device is used with a forced air type furnace, the device in addition provides heat interchange between room air and the hot gasses in the trap. This then heated air is drawn into the circulating system of the furnace adding to its temperature while lowering the temperature of the vented combustion gasses, to lessen the heat loss up the chimney.

Abstract: A heater venting system in which a draft hood which connects at its upper end to a chimney, which has an open lower end and which has an opening intermediate its upper and lower ends connected to the heater exhaust flue has its open lower end connected for gas flow to a chamber which is open to the building inside air at its upper end and which is connected at its lower end to air outside the building by a damper controlled duct to provide an inside air-outside air interface at, or above the lower end of the hood to restrict the flow of building inside air into the hood.

Abstract: A gas burning furnace system is disclosed, including a blower which draws air from outside the home for combustion. The blower forces combustion air to the gas burner via a pressure box situated between the blower and the burner. The pressure box encloses a barrier having an adjustable aperture therein, through which the combustion air must pass before reaching the burner. By adjusting the size of the aperture, the rate of supply of combustion air to the burner can be regulated so as to produce complete fuel combustion without cooling the firebox.

Abstract: This invention relates to a device which is installed in series with the smoke stack of an oil burner whereby the configuration of the device provides the means to act as an aerodynamic check valve and to stabilize and isolate downdraft effects in the smoke stack of a burner caused by adverse or varying wind conditions so as to insure against subsequent faulty burner operation. Also, the use of this invention, and its objectives, has application in the smoke stack of other like heating entities or duct work requiring the movement or discharge of gases; some of which are wood burning stoves, coal burning stoves or gas burning heating equipment.

Abstract: A housing structure with a single pivoted damper member is provided as a replacement for the draft hood associated respectively with the flue outlet and vent pipe inlet in a gas heater system. The normal flue outlet for the gas system connects to a first passage in the housing and the normal overhead vent inlet connects to a second passage in the housing above the first passage. First ends of the passages adjacent to their connections to the flue outlet and vent pipe inlet are closed off and second ends open out in a common plane. Communicating with the second ends is an ambient atmosphere opening so that under conditions where the second ends of the passages are open, proper exhausting of gases passing up through the flue to the vent takes place. The single damper itself is mounted to swing in a manner to close off both passages simultaneously when in a first position and also isolate these passages from the ambient atmosphere inlet. In this first position, heat is retained in the heater as well as the room.

Abstract: A venting system for a fuel-burning heating plant, such as a conventional gas-fired furnace. The venting system includes an open-bottomed diverter situated well above the base of the heating plant having vertically disposed inlet and outlet ducts attached to the diverter top. The inlet duct is also attached to the flue outlet of the furnace, while the outlet duct is attached to a chimney flue for expulsion of combustion gases. A heat retention means, such as a damper or a heat-absorbing cone, is located within the inlet duct to permit absorption of heat from passing combustion gases during the combustion cycle and maintain heat in the inlet duct during cessation of the combustion cycle in order to establish a heat lock within the inlet duct and the diverter to prevent the flow of relatively cooler air through the furnace combustion chamber and up the chimney during cessation of the combustion cycle. A similar heat retention means may also be located within the outlet duct.

Abstract: An automatic damper means and controls, which provide an exceedingly safe automatic damper for the exhaust duct-work of an associated gas furnace or the like, by automatic control of the damper, and automatic control of the gas supply, with redundancy features for providing exceedingly safe operation.

Abstract: An energy conserving device for preventing loss of heat energy from a heater to a chimney by means of a fluid gas heat trap to choke off either chimney draft and/or heated convectional air currents lost to the chimney when the heater is OFF but allowing combustion gasses to vent freely to the chimney when such gasses are generated. The device also acts as a diverter for either up or down drafts from the chimney to direct them away from the heater. In another form when the device is used with a forced air type furnace, the device in addition provides heat interchange between room air and the hot gasses in the trap. This then heated air is drawn into the circulating system of the furnace adding to its temperature while lowering the temperature of the vented combustion gasses, to lessen the heat loss up the chimney.

Abstract: This invention is an enclosure for the part of a gas heater vent which protrudes on the outside of a wall of the building in which the gas heater is installed. It consists of a sheet metal rectangular baffle which encloses the front, sides, and part of the top of the vent part, and is attached to the wall of the building. A variation of the invention provides for the easy removal and reattachment of the baffle; and another variation fully encloses the top and bottom of the baffle; provides a chimney for the discharge of gases at the top of the baffle, and a rain and snow shield for the top of the chimney.

Abstract: A venting system for gas fired heating plants including a diverter box, conduit means for conducting gas from one heating plant upwardly in one leg of an inverted U pattern and downwardly into the second leg of such pattern while admitting air at the bottom of the box to form a heat lock to restrict the flow of air in this pattern, and a second conduit means for conducting gas from a second heating plant upwardly and then downwardly of the second leg of the pattern for the first heating plant to a level at which gas may be passed within the box from the inlet to the outlet of the box, thus providing a structure which avoids the blowing out of the pilot flame in one or another of the heating plants.

Abstract: A seal for flow passages has directional characteristics allowing gases or fluids to flow freely in one direction while restricting the flow in the opposite direction. The seal includes a flow diverter cone (or other inclined surface) which is spacedly mounted on a flow inverter cone (or other inclined surface) in a passage to effectively reverse the direction of undesired counterflow of gases without restricting normal gas flow. The seal has no moving parts but serves as an effective aerodynamic valve. Addition of this seal to the stack of a flare system, or to other chimneys, restricts the flow of air into the stack while allowing the waste gases to be exhausted with negligible restriction.

Abstract: A venting system for the combustion chamber of a gas-fired heating plant has an elongate diverter box arranged vertically of the heating plant exteriorly thereof and having an upper portion and a lower portion with the latter having a bottom provided with a substantial opening disposed well above the base of the heating plant for the free admission of atmospheric air surrounding the heating plant into the diverter box and with the upper portion having selected openings for the reception of horizontally disposed pipings from the flue outlet for the combustion chamber and for the chimney flue with a vertical baffle depending from the closed top of the upper portion a substantial vertical extent into the diverter box and dividing it into a flue outlet section and a chimney flue section with said sections having thermostat means to indicate exteriorly of the sections the temperature of the gases therein and with a safety limit switch housed in the flue outlet section below the lower free end of the baffle and bei

Abstract: An apparatus for reclaiming heat from and for controlling the flow of combustion gases passing through a flue from a heater to an exhaust stack. The apparatus includes an inner housing having first inlet and outlet openings. The first inlet opening is adapted for connection by one section of the flue to the heater, whereby combustion gases from the heater will enter the inner housing through the first inlet opening and will exit therefrom through the first outlet opening. An outer housing at least partially surrounds the inner housing, the said inner and outer housings being spaced one from the other to define an intermediate chamber which is in communication with the inner housing's first outlet opening. The outer housing is provided with a second outlet opening which is aligned with the first outlet opening and in communication with an integral damper housing which is in turn adapted for connection by another flue section to the exhaust stack.

Abstract: This is a unique and improved throat for chimneys such as chimneys used in connection with fireplaces which features a complete former damper and throat attached to the sides of the chimney hood portion immediately above the firebox in such manner as to provide a chamber into which downdrafts from the chimney will be directed so as to be diverted back up the chimney and wherein the draft from the firebox or combustion chamber together with smoke will be diverted up the chimney so that if diverted otherwise by downdraft it will enter the air shelf and return up the chimney; the invention is further characterized by the capability of being formed of cardboard or the like in an inexpensive manner which will burn away, and leave the masonry which has been formed thereabout as the final unit; the air shelf is provided with unique cleaning potential through provision of a washing opening.

Abstract: A venting system for a warm-air furnace, gasfired boiler or the like heating plant has an open bottom diverter box which is arranged horizontally externally of the heating plant substantially at the level of the top thereof. The top wall of the diverter box at one end section thereof is connected by a vertically upstanding U-shaped, internally unobstructed, ducting to the top of the combustion chamber of the heating plant so that fumes flow therethrough into such combustion chamber end section of the box while the top wall of the diverter box at the other end section is connected by a vertically upstanding, internally unobstructed, piping to the flue.

Abstract: An air terminal for a horizontal vent of a sealed combustion furnace includes a faceplate for mounting to an exterior vertical wall. A horizontal flue pipe extension, receiving the combustion products, is surrounded by an oval sleeve. Fresh air is communicated to the furnace through the space between the flue pipe and the sleeve. The outlet of the flue pipe is at least about 3/4 in. outside the faceplate. An enlarged fresh air intake opening exists about the flue pipe, and a pocket-shaped rain shield is located beneath the flue pipe extending upwardly and inwardly. A horizontal wind deflector vane is located beneath the flue pipe and extends across the width of the fresh air intake opening for directing incident wind downwardly along the wall. The terminal improves operation of the furnace under all wind conditions, whether the furnace is operating on pilot or main burner modes.

Abstract: A down-draught deflector - draught interrupter is described having a tube of circular or rectangular cross-section, an internal baffle element for laterally deflecting down-draught gases and peripheral escape openings for such gases. The tube has a substantially constant diameter and is provided in one end portion (upstream end portion) with an annular combustion gas deflector for deflecting combustion gases towards the tube axis and defines a gas flow path which at the position of its smallest cross-section has a diameter of 0.3-0.9 times the internal diameter of the tube.The baffle element occupies within the tube a position wholly or mainly downstream with respect to said position of smallest flow-path cross-section and has a dimension in a plane normal to the tube axis of 0.2-0.9 times the internal diameter of the tube. The apertures in the tube wall are located so as to be at least in part opposite the baffle element.

Abstract: An automatic damper means and controls, which provide an exceedingly safe automatic damper for the exhaust duct-work of an associated gas furnace or the like, by automatic control of the damper, and automatic control of the gas supply, with redundancy features for providing exceedingly safe operation.

Abstract: A flue control device for slowing the rate at which heated exhaust gases rise through an exhaust stack comprises a cylindrical housing enclosed by end caps, with an offset inlet and outlet being positioned in opposite end caps. The interior of the housing defines a baffle chamber, and a baffle mechanism is positioned in the baffle chamber between the inlet and outlet. The baffle mechanism comprises two overlapping plates, each plate having a prominent flange extending in an upstream direction relative to the flow of gases through the baffle chamber. The flanges interrupt and slow the swirling circular flow of gases as they pass through the baffle chamber. The baffle and housing are of a size such that the cross-sectional area of the restricted portion of the housing adjacent the baffle is at least as large as the cross-sectional area of the exhaust stack.