Abstract: An HVAC air distribution device to promote temperature stratification within a larger volume. The device comprised of a front side coupled to a back side defining a cavity for directing a flow of air. The front side comprised of a pliable material and configured for the distribution of the flow of air within the channel. Accordingly, the front side comprises an air permeable portion to release flow from the channel to provide a low velocity of uniform air flow across a length of the device. This low velocity uniform air flow encourages temperature stratification within a distinct area of the larger volume to increase comfort of an occupant and promote efficiency of HVAC systems.

Abstract: A system includes a condensing unit, a valve, and a unit cooler. The condensing unit is configured to condense refrigerant. The valve is configured to control the flow of the refrigerant from the condensing unit to the unit cooler. The unit cooler is configured to operate in a refrigeration mode and a stir-cycle mode. The unit cooler is configured to operate at a first speed during the refrigeration mode and at a second speed for a first period of time and at a third speed for a second period of time during the stir-cycle mode. The second speed is slower than the first speed and the third speed is slower than the second speed. Electric power is supplied to the unit cooler throughout the refrigeration mode and the stir-cycle mode.

Abstract: Auxiliary heat ejectors (380A, 490) having an optional independent circulator module (380D), heat exchange radiators (41e, 41f), heated fluid inlet lines (21e, 21f) and exchange fluid return lines (47e, 47f) with pumps (49e, 49f) connected to other tandem modules such as heat sources (30E, 40F) incorporated by reference, a flexible helical corrugated body (53e) or a retractable modular unite walls (53f) on cart wheels (25f), actuators (23e, 23f), partitions (35e, 37e, 37f), inlet and outlet end having flanges (45e, 45f, 35g) for connecting with shared ductwork of a primary heater. The independent circulator module (380D) comprises of a flexible body (41g), support (21g), flow check gate (31g), a blower motor (27g) with propeller 25g.

Abstract: A heated air makeup unit comprising a heating chamber with a modulated furnace one or more non-modulated furnaces air temperature control and efficient furnace operation over a wide heating rate range. The utilization of indirect fired furnaces in the heated air makeup unit is disclosed. A control system is included to provide control of heated air temperature to within +/?1 F.° using continuous control of the heating rate of the modulated furnace and stepwise activation and de-activation of the non-modulated furnaces in response to heating demand. A programmed combustion air flow controller programmed to provide optimal airflow for any gas flow in a flow range of a modulating gas valve is provided to assure combustion efficiencies of at least 83%.

Abstract: Provided herein are embodiments of a multistage gas furnace, a controller therefor and a computer-usable medium having non-transitory computer readable instructions stored thereon for execution by a processor to perform a method for operating a gas furnace. In one embodiment, the gas furnace includes: (1) a burner, (2) a circulation fan and (3) a furnace controller. The furnace controller having: (3A) an interface configured to receive heating calls and a blower control signal, the blower control signal corresponding to an operating speed of the circulation fan and (3B) a processor configured to respond to the heating calls and the blower control signal by setting and adjusting a gas input rate for the burner that is based on the blower control signal and that corresponds to a discharge air temperature determined by a dedicated discharge air sensor associated with the furnace.

Abstract: A vent hole 12 is provided in the upper part of a front panel 1e of an outer case 1. Air in a room having passed through a section in which a main heat exchanger 6 is arranged is led to the vent hole 12 through a space between an upper plate 1b of an outer case 1 and an upper wall 2d of a combustion housing 2. A drain dish 18 is arranged on the upper face of the upper wall 2d of the combustion housing 2.

Abstract: The room heater has, in an outer case 1, both a first air flow passage that leads to a vent hole 12 through a section in which the main heat exchanger 6 is arranged and a second air flow passage that does not pass through the section in which the main heat exchanger 6 is arranged but leads to the vent hole 12 through a section in which a supplementary heat exchanger 6? is arranged provided. At least one of the first damper 20 which can freely block the first air flow passage and the second damper 21 which can freely block the second air flow passage is provided, and the first air flow passage or the second air flow passage is blocked in a weak combustion period.

Abstract: This invention relates to a heating device consisting of at least one burner for the combustion especially of a gaseous fuel, at least one radiant tube connecting to the burner, at least one fan generating a negative pressure or an excess pressure in the radiant tube, and at least one exhaust gas recirculation system with at least one exhaust gas recirculation passage through which an exhaust gas produced during the combustion of the primary fuel can be recirculated from the radiant tube to a transition zone from the burner into the radiant tube. In order to further develop a heating device of this type as well as a method for its operation the burner is adapted for being operated in at least two power stages and the exhaust gas recirculation system is controlled in dependence of the power stages of the burner in such a way that the volume flow of the recirculated exhaust gas is reduced with an increasing power stage of the burner.

Abstract: The invention is directed to a combination heater and electrical generator designed to allow continual use of the heating system in the absence of an external source of electricity. The system shares fuel and electrical inputs and also shares exhaust outputs so to facilitate ease of use installation as well as affording a small installation footprint.

Abstract: An HVAC burner box includes a burner bank, a manifold and an air director located within an enclosure. The burner bank is oriented such that an outlet end of the burner bank is directed toward a first end of the enclosure. The manifold is located within the enclosure and adjacent an inlet end of the burner bank. The air director has a diffuser that is coupled to a side of the enclosure. The diffuser includes a plurality of openings located therethrough. The diffuser is configured to direct a first portion of a received airstream through the opening and toward the burner bank. The diffuser is further configured to send a second portion of the received airstream toward the manifold.

Abstract: A heated air makeup unit comprising a heating chamber with a modulated furnace one or more non-modulated furnaces air temperature control and efficient furnace operation over a wide heating rate range. The utilization of indirect fired furnaces in the heated air makeup unit is disclosed. A control system is included to provide control of heated air temperature to within +/?1 F.° using continuous control of the heating rate of the modulated furnace and stepwise activation and de-activation of the non-modulated furnaces in response to heating demand. A programmed combustion air flow controller programmed to provide optimal airflow for any gas flow in a flow range of a modulating gas valve is provided to assure combustion efficiencies of at least 83%.

Abstract: In an in-wall heater, in which control equipment 11, 12 is disposed in a side space 10 on one lateral side of a combustion housing 2 within an outer case 1 and an exhaust duct 15 is disposed in a side space 13 on the other lateral side of the combustion housing 2, the cooling performance of each of the side spaces is increased and noise due to a sucked-in sound of room air can be reduced. In a side plate portion of the outer case 1 on both lateral sides, an air intake opening 7, which is vertically long, is provided in a position in a front side portion exposed to a front of a room wall. Each side space 10, 13 within the outer case 1 is formed in a ventilation flue on the suction side where the room air from each of the air intake openings 7 is conducted into the warm air fan 9.

Abstract: An indoor space heating apparatus comprising a heat pump including indoor and outdoor heat exchangers in fluid communication with a heat pump compressor. A blower is positioned to blow air over heat rejection coils of the indoor heat exchanger and into an indoor warm air reservoir. A combustion engine drives the heat pump compressor and a furnace transfers combustion heat from the combustion engine to the indoor warm air reservoir.

Abstract: A vent hole 12 is provided in the upper part of a front panel 1e of an outer case 1. Air in a room having passed through a section in which a main heat exchanger 6 is arranged is led to the vent hole 12 through a space between an upper plate 1b of an outer case 1 and an upper wall 2d of a combustion housing 2. A drain dish 18 is arranged on the upper face of the upper wall 2d of the combustion housing 2.

Abstract: The room heater has, in an outer case 1, both a first air flow passage that leads to a vent hole 12 through a section in which the main heat exchanger 6 is arranged and a second air flow passage that does not pass through the section in which the main heat exchanger 6 is arranged but leads to the vent hole 12 through a section in which a supplementary heat exchanger 6? is arranged provided. At least one of the first damper 20 which can freely block the first air flow passage and the second damper 21 which can freely block the second air flow passage is provided, and the first air flow passage or the second air flow passage is blocked in a weak combustion period.

Abstract: An apparatus for extracting heat from a heat source comprising a housing having a first end with a first opening and a second end with a second opening. The housing includes an internal compartment therein and the first end of the housing is connected to said heat source. A channel extends from the housing for providing access to the internal compartment. A hollow conduit is positioned within the internal compartment extending between the first opening and the second opening. A plurality of members are positioned on an exterior surface of the conduit and along the length thereof. The members are able to absorb heat from within the conduit and release the absorbed heat into the internal compartment creating heated air. The apparatus includes a means for drawing air through and expelling air from said conduit and means for moving said heated air out from said internal compartment to a second compartment. The apparatus is activated via means connected to each of the drawing means and the moving means.

Abstract: The need to maintain the quality of air in a home has become more of a problem in new high efficiency tight houses so that governmental regulations are being proposed for a minimum change of fresh air. If too much cold outside fresh air is introduced into such homes at a single source, the room with the fresh air is usually too cold and/or unbalanced. The present invention avoids cooling any one room while maintaining heat efficiency. When the home has a gas fireplace, the exhaust gases are preferably directed through an air-to-air cross flow heat exchanger which preheats the quality air passing into a forced air furnace system. In modified embodiments of the present invention, make-up quality air is mixed with the room air and heated in the heat exchanger of the fireplace. The preheated room air from the fireplace is preferably connected to the supply/return of a forced air furnace system and distributed to all rooms to provide uniform heating.

Abstract: An improved furnace is provided which can be field modified to change the pressure drop across the inducer. The pressure drop is modified to accommodate vertical or horizontal venting and adequately lined and inadequately lined chimneys. A first rate of flow of combustion byproducts into the vent system is used when the chimney is adequately lined and a second relatively higher rate of flow is used when the chimney is inadequately lined. The rate of flow is changed by inserting or removing an obstruction in the flow of combustion byproducts. The obstruction could be a tab or choke placed at the inducer outlet or a similar device in the inducer inlet. When the tab is in place the flow of combustion byproducts is reduced. When the tab is removed, the flow rate increases. Alternatively, the inducer inlet could be adjusted to increase or decrease the amount of air flow through the inducer.

Abstract: A heat recovery device for use with a portable incinerator. The heat recovery device comprises first and second legs which support a heat exchanger thereon. An air flow path is formed from the bottom to the top of the first leg, through the heat exchanger and from the top to the bottom of the second leg. An open space is provided between the two legs and below the heat exchanger. A portable incinerator may be placed within this open space. When solid waste is burned within the incinerator, the exhaust port of the incinerator lies below the heat exchanger. A blower attached to the lower portion of the first leg creates air flow through the heat recovery device such that the air is heated in the heat exchanger by heat produced from the exhaust port of the portable incinerator. A tube is then coupled to the second leg in order to direct the heated air flow to the interior of an adjacent building.

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 low fluid indicator for a fluid injection system of the type having a sealed pressurized canister, and a valve responsive to a control signal to release fluid from the canister includes a counter that maintains a count. A pulse generating circuit increments the count by a first increment and a second increment in response to the control signal. The first increment is insensitive to the duration of the control signal above a threshold duration and is selected in accordance with a fill volume of the injection system. The second increment varies with duration of the control signal above the threshold duration and has a count rate selected in accordance with an injection flow rate of the injection system. A low fluid indicator lamp is responsive to the counter to indicator a low fluid condition when in the canister when the count exceeds a selected value.

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: The room heating arrangement is provided with a radiation tube, connected to a pressure and mixing chamber casing 1, a pipe line system arranged above the room to be heated, the radiation tube being connected, on the one hand, to a return flow chamber 19 with fan 10 and, on the other hand, to a mixing chamber 20 with a flame tube 14 surrounding a burner 2. The pressure and mixing chamber casing 1 is constructed in double-worm form, two cylindrical parts 26, 27 forming the casing and a front and back plate 3, 4 presenting the double-worm form, while the connecting tubes 18, 21 for the radiation tube are connected to the back plate 4. The burner 2 and the drive unit 5 for the fan 10 are arranged on the front plate 3.

Abstract: The humidity of a heated space is regulated by varying the amount of moisture transferred from the combustion gases of the furnace used to heat the space. A porous heat sink element is arranged to move through the path of the combustion gases and one or more reclaim-air paths. The heat sink member can take any of a variety of forms; it can reciprocate back and forth along a track, or it can be configured as a rotating wheel ("heat wheel"). The amount of moisture transferred from the combustion gases to the reclaim air is governed by a humidity signal. If the humidity signal calls for a change in humidity, one of several parameters is varied to provide for a greater or lesser transfer of moisture from the combustion gases to the reclaim air.

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: Provided is a hot-air type heater including a heat generating means such as a burner heater from which hot air is produced and blown out the heater into a living room so as to warm up the inside of the room with a uniform temperature distribution even among various heating rate conditions. The hot-air heater includes at least of variable angle louvers which are vertically swingable, and a control means for swinging the louver in association with at least either a hot air flow rate at a hot air outlet opening of the heater or the heating value of the heat generating means, so that the louver is vertically swung in accordance with an output from the control means in order to minimize differences in temperature distribution in the room during operation of the heater under various heating conditions.

Abstract: Air conditioning apparatus with an enclosure which both houses a conditioning coil and serves as a plenum for transferring air to one or more conduits. In one aspect, vanes of the coil or coils are oriented to direct air toward openings in the plenum. An enclosure that serves as a coil housing and as a plenum.

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: There are disclosed means and method for improving the efficiency of combustion in an automatic gas-fired furnace through retardation, without restriction of the exhaust emission of the products of combustion, which are caused to dwell longer in the combustion chamber to elevate the temperature, not only through the impoundment of what would otherwise be waste heat, but by the conversion of CO gas and excess air to CO.sub.2 gas, thus, reducing the two former, increasing the latter, along with temperature. This reduces the condensate in the exhaust chimney. An enlarged chamber in the exhaust gas conduit is incorporated within the line of exhaust flow from furnace to chimney. A baffle plate, approximately equal in area to the cross-sectional area of the conduit, is immovably secured in the chamber normal to the line of exhaust flow. The chamber is completely closed except for the exhaust flow entry and exit ports.

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: The invention provides a compartmented gas fired heater in a cabinet-type outer stove casing. The outer stove casing has a downwardly positioned covered bottom with adjustable legs at four corners and an upwardly positioned opened top edge. A heat chamber insert having a covered bottom and an opened top is fitted inside the outer stove casing and retained so a corridor exists between all wall surfaces and the two bottoms. The top of the two sections are covered over the corridor area by a framing cover leaving the top of the heat chamber insert open as a hot air outlet. A caged outlet cover fits over the hot air outlet. Cool air is passed into the heat chamber insert through an air inlet casing. When a controlled gas burner is fired in the corridor below the bottom of the heat insert chamber, heat spirals up the corridors, is conducted through the outer stove casing and through the heat chamber insert walls and convected up through the top hot air outlet.

Abstract: A flue gas/combustion air heat exchanger for a furnace. The furnace includes a combustion chamber that burns a mixture of fuel and combustion air to produce heat for a comfort zone. The resulting products of combustion, along with any waste heat not transferred to the zone, pass through a flue duct before venting to atmosphere. Incoming combustion air is discharged across the relatively hot flue duct before it enters the combustion chamber. In passing across the hot flue duct, the incoming air is preheated by waste heat of the combustion products. The heat exchange relation between the incoming combustion air and the combustion products within the flue duct enables the furnace to recover waste heat that would otherwise be lost if the combustion products were free to discharge to atmosphere before giving up a portion of their waste heat to the incoming combustion air.

Abstract: Heat transfer structure for transferring heat from products of combustion to air to be conditioned in a furnace. The heat transfer structure includes an inlet portion receiving hot products of combustion from a burner and extending generally transversely to the direction of the flow of air to be conditioned by heat transfer association therewith. The heat transfer structure further includes at least three successive legs extending generally parallel to the direction of air flow. In one form, the transverse leg is disposed at the inlet portion of the air flow passages, and in a modified form, the transverse leg is disposed remotely therefrom. In the illustrated embodiments, the air moving structure is disposed in a lowermost portion of the cabinet, with the transverse inlet leg of the heat exchanger being selectively disposed lowermost or uppermost to define the two selective arrangements.

Abstract: A compact, high efficiency hot air furnace including a heat exchanger assembly located in a heat exchange chamber through which comfort air is passed to be heated. The heat exchanger assembly includes a drum-like combustion member located such that its axis extends across the flow path of comfort air. A supplementary heat exchanger or condenser is located a spaced distance from the combustion member and is disposed in the comfort air flow path upstream from the combustion member. A transfer channel extends from one end of a cylindrical wall forming part of the combustion member and communicates combustion by-products to the condenser. Heat exchange fins are mounted to the cylindrical wall of the combustion member and along a wall of the transfer member. A diffuser located within the combustion member is cup-shaped and includes a wall portion positioned between a burner and a transfer channel opening which prevents the burner flame from extending into the transfer channel.

Abstract: An air purification system for use with an air conditioning apparatus which includes an air circulation system having supply air flow to a given area and return air flow for drawing air from that area. The air purification system includes an inlet and an outlet. A conduit communicates the inlet with the air circulation system for drawing therefrom a portion of the air passing therethrough. A conduit communicates the outlet with the air circulation system downstream of the inlet for returning the portion of the air back to the circulation system after it has passed through the air purification unit. A superheating conduit also communicates between the inlet and an exhaust of the air conditioning apparatus, such as the chimney of a furnace.

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 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 flue gas heat pump is provided for extracting heat from the discharged hot flue gas of a furnace. The heat pump includes a condenser at the inlet of the furnace cabinet in heat transfer relation with the flow of air to be conditioned, and an evaporator disposed at the outlet of the furnace heat exchanger for extracting heat therefrom. A compressor is provided for compressing a refrigerant and delivering it to the heat exchangers. The compressor is located in the flow path of the air to be conditioned so that the heat generated by the compressor is transferred thereto.

Abstract: An apparatus having a heating chamber, (combustion chamber) a heat storing means and heat transferring means of the kind used in households, commercial furnaces, heaters, boilers, etc., having a heating chamber which is spherically arranged; with ports for receiving fuels and a valve for regulating the internal pressure and temperature, allowing for excessive heat to be exhausted into a secondary heat recovery manifold. The spherical heating chamber allows the heat to radiate uniformly. Said heat is stored by mantle material. Said mantle being entirely surrounded by a crust layer and insulating means and an outside protective covering. The apparatus also having means for transferring the stored heat for heating purposes as is generally in common use.

Abstract: A heater for combustion of carbonaceous fuels comprising a casing which surrounds and contains the fuel immediately prior to and during combustion and a heat exchanger of unique design which is positioned within the casing. The efficiency of the heater may be increased by providing an improved system for supplying pre-heated secondary air for more complete combustion of partially combusted fuel in the general vicinity of and/or within the heat exchanger. The heater may be of the self-feeding type for combustion of solid fuels such as wood and, in this embodiment, preferably the casing is generally cylindrical and the heat exchanger is approximately centrally located within the casing whereby it extends generally along the casing axis and is spaced a substantial distance from the casing wall.

Abstract: A heat extractor system for a furnace, said furnace including a burner with a chimney that is connected but is normally not in operation. Instead, the furnace is connected to a vent in parallel with the chimney through a draft-inducing arrangement including a water spray in which water is heated and circulated to a point where the heat from the water is utilized. Due to the parallel arrangement of the vent and chimney, if the vent fails to operate, it will function in a fail-safe manner, with the combusted gases from the burner leaving through the chimney.

Abstract: A system is disclosed for recovering heat from high temperature combustion gases escaping from a heater such as for examples a domestic warm air furnace, boiler or the like. The system includes a first conduit leading to a chimney and a second conduit leading to a heat recovery unit which in turn is connected to a vent. A "T" connection interconnects the first and second conduits to each other and to the heater. The heat recovery unit artificially induces a draft in the second conduit which overcomes the natural draft induced in the first conduit by virtue of its connection to the chimney. An accelerator in the T connection increases the velocity of combustion gases flowing past the first conduit into the second conduit.

Abstract: This invention relates to a compact high efficiency furnace having a cylindrical combustion chamber and a fin and tube type heat exchanger substantially parallel, transverse to the furnace air flow, and closely spaced in the air flow direction with no other major heat exchange being utilized. Condensation of fluids from the combustion gases occurs at the fin and tube type heat exchanger, whereby a high efficiency furnace results. The fins and tubes of the heat exchanger are of different materials, requiring that the combustion gas temperature at the heat exchanger inlet be limited.

Abstract: A furnace for wood log fuel having apparatus which automatically inserts the logs into the furnace combustion chamber. The log fuel is retained in a sloping ramp storage compartment. Electrical circuitry controlled by a thermostat operates to move a log into an elongated chamber from which a motor driven injector pushes the log into the combustion chamber through a doorway covered by a flexible, segmented flap covering and also a door which is pushed open by the advancing log. The presence of the log on a spring mounted grate operates certain switches to return the injection mechanism to its ready condition and also to operate a fan which provides combustion air to the combustion chamber. The reduced weight on the grate by the consumption of the log by the fire permits the grate to move to a position to re-initiate the log injection cycle.

Abstract: The heating equipment includes an auxiliary heating apparatus having a space heater mounted within an air recirculating furnace system for heating air therein. A thermostat responds to a first predetermined ambient temperature to activate the space heater for heating air within the furnace system. A conduit, connected electrically between the output of the thermostat and the air recirculating blower of the furnace system, sends an electrical signal to the blower to activate it when the thermostat is energized upon the ambient temperature falling below the first predetermined temperature.

Abstract: Control circuits are provided for a heat exchange unit including environment responsive means placed in the general area of the heat exchange unit's heat exchanger or of the associated heat distribution network or return system. The environment responsive means is connected in series between the heat exchange unit's main control switch, such as a thermostat, and the fuel valve which controls the flow of fuel to the unit's burner. The environment responsive means may be either independent of, or connected in parallel with a heat circulator if any, associated with the unit's heat exchanger. The control circuits of the present invention control the action of the heat exchange units fuel valve to create an intermittent heating flame in response to environmental changes at the heat exchanger, heat distribution network or return system during each heat demand cycle.

Abstract: Furnace structure including an outer enclosure divided into a cool air chamber and a hot air chamber separated by a combustion gas chamber through which heat exchange tubes pass air between the cool air chamber and the hot air chamber. The furnace structure further includes a burner in the combustion gas chamber, a blower connected to the cool air chamber and a flue for the combustion gases including a draft diverter therein.

Abstract: A control unit for make-up air and combustion air is disclosed for use with a furnace in an air circulating system for a building. A baffle having a combustion air inlet and a make-up air inlet is provided with a weather protective hood and adapted to be mounted on the outside wall of a building. The combustion air inlet is connected through a conduit to a location adjacent the floor of the building on which the furnace is mounted. The baffle includes a restrictor plate including a pair of openings aligned with the combustion air and make-up inlets, respectively, and including a screen extending across the openings. The baffle includes a damper in the make-up air inlet which opens in response to reduced pressure in the furnace return air duct so that the inside pressure tends to be equalized with the outside pressure.

Abstract: A control unit for make-up air and combustion air is disclosed for use with a furnace in an air circulating system for a building. A baffle having a combustion air inlet and a make-up air inlet is provided with a weather protective hood and adapted to be mounted on the outside wall of a building. The combustion air inlet is connected through a conduit to a location adjacent the floor of the building on which the furnace is mounted. The baffle includes a restrictor plate including a pair of openings aligned with the combustion air and make-up air inlets, respectively, and a screen extending across the openings. The baffle includes a damper in the make-up air inlet and a damper in the combustion air inlet. The dampers are mounted on a common shaft so that they move concurrently in response to a pressure differential between the inside and outside.

Abstract: A heat extractor system for a furnace, said furnace including a burner with a chimney that is connected but is normally not in operation. Instead, the furnace is connected to a vent in parallel with the chimney through a draft-inducing arrangement including a water spray in which water is heated and circulated to a point where the heat from the water is utilized. Due to the parallel arrangement of the vent and chimney, if the vent fails to operate, it will function in a fail-safe manner, with the combusted gases from the burner leaving through the chimney.

Abstract: The present invention is an enhanced tubular heat exchanger for a furnace with the heat tubes of the heat exchanger having two straight sections connected by a bend. 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.