Abstract: A heat control device for a stove which burns solid fuel and in which the heat output of fuel combustion is regulated in order to control within preselected temperature ranges the temperature of the combustion chamber of the stove and the ambient air temperature of the environment being heated by the stove.

Abstract: An automatic damper device constructed to be integrated in multiple units into forced air heating and cooling systems for the purpose of controlling and regulating air flow to all rooms, individually and concurrently, within a dwelling; the automatic damper means incorporating a damper housing having a rotatable damper plate connected by flexible cable to dual solenoid motor means that are energized through dual switch means. Damper housing is installed in duct boot terminating in room register, and damper plate is rotatable between open and closed positions by said cable means attached to common solenoid plunger when automatic damper device responds to commands from associated room thermostat that controls damper motor means and combustion cycle of combustion means.

Abstract: A blower override system and control for forced air systems such as heating or cooling systems in which an override relay starts the blower to circulate the warmed or cooled air when the heating or cooling element turned on. When the heating or cooling is turned off, the blower is thereupon allowed to continue by the override unit to function for a timed interval by a time delay relay. The unit is in a control box and ready to attach to existing control structures for forced air systems.

Abstract: A control system for a humidifier, associated with a hot air furnace, that attains a high level of relative humidity without causing any condensation on the building interior by varying the level of operation of the humidifier as a function of the rate of heat loss from the building. Since the duty cycle of the furnace is a function of the rate of the heat loss, the system generates a digital signal related to the duty cycle and uses that signal to interrogate a digital memory storing a program of desired humidities for various duty cycles to output an instantaneous desired humidity signal which is compared with a measured humidity signal to develop an on/off control signal for the humidifier.

Abstract: An electronic thermostat operative to be connected to a furnace or other temperature modifying apparatus, to control its state of operation, includes means for generating a desired temperature set point signal and means for measuring ambient temperature on the thermostat. When the ambient temperature falls below the set point the furnace is energized for a predetermined period of time. The time of energization is increased or decreased by a small increment after each heating cycle depending upon magnitude of the temperature increase which occurred at the thermostat as a result of the heating cycle in order to adaptively achieve a predetermined temperature increase during the heating cycle and the thermal overshoot period which occurs following de-energization of the furnace.

Abstract: This invention relates to a DC powered emergency heating system control circuit for use in combination with a gas furnace that includes an AC power supply for a thermostat to control a normally operated AC powered automatic gas valve, which gas valve provides gas for burning in a plenum chamber. The control circuit includes an auxiliary fan and circuits responsive to the interruption of AC power to provide in a repetitive sequence, DC power pulses of one polarity to the automatic gas valve, followed by energization of the auxiliary fan, followed by the application of DC power of an opposite polarity to the gas valve. This repetitive sequence thereby ensures alternate periods of convection and auxiliary fan induced forced air heating while simultaneously protecting the normally AC powered gas valve from the deleterious magnetism effect brought on by the continuous emergency DC powered operation of the gas valve.

Abstract: A temperature responsive blower control attachment for a wood-burning stove. The attachment is mountable to or seatable on a heated external surface of the stove and provides thermostatically regulated operation of an electrically operated blower or fan that circulates air heated by the stove. Temperature is sensed through an element which is in contact with the heated surface of the stove, but the other circuit elements of the attachment are isolated from and are not subjected to the potentially damaging temperature of the stove surface.

Abstract: A solid fuel furnace is disclosed as including a firebox disposed inside of a heating chamber through which air to be heated is passed. A pair of baffles guides the air through the heating chamber to progressively heat the air. In addition, an auxiliary air system is provided to inject air into the fire when there is a heating demand to increase combustion and provide more heat when it is most needed.A modified solid fuel furnace is also disclosed which includes a combustion chamber having a door designed to prevent flash-back when the door is opened, a valve for preventing a flow of combustion air to the combustion chamber when the temperature in the combustion chamber rises above a present level, and a manual override for the valve.

Abstract: There is disclosed an air-to-air heat exchanger which is positioned in a fireplace. The heat exchanger comprises a grate structure on which logs are burned. Ambient air is circulated through the heat exchanger and is heated. Hot air exiting from the heat exchanger is delivered into a metal conduit extending vertically into the chimney. An opening is formed in the chimney wall in the attic of the building and hot air is delivered into ductwork in the building attic. A damper is provided in the fireplace which seals about the conduit extending vertically into the chimney in the closed position of the damper. Air flow through the conduit and heat exchanger may be reversed.

Abstract: A furnace having a burner fired heat exchanger with a flue gas passage and a heated air passage, a blower powered by an electric motor for circulating the heated air and an electric control circuit with a normally closed relay connecting the blower motor to the power source, the relay being controlled by a "Schmitt trigger" connected to a timing combination.

Abstract: A heated air distribution system for a forced air heating system of a home or the like for distributing heated air preferably from a higher heated area to a lower heated area. The heated air distribution system utilizes the air return ducts of the forced air heating system which are common to the higher and lower heated areas. The heated air distribution system comprises an air forcing device coupled to the air return ducts for forcing heated air from the higher heated area through the air return ducts to the lower heated areas. This equalizes the temperatures of the air in the two areas, prevents overheating of the higher heated area and conserves energy.

Abstract: A solid fuel furnace is disclosed as including a firebox disposed inside of a heating chamber through which air to be heated is passed. A pair of baffles guides the air through the heating chamber to progressively heat the air. In addition, an auxiliary air system is provided to inject air into the fire when there is a heating demand to increase combustion and provide more heat when it is most needed.

Abstract: Control apparatus for regulating the operation of a warm air furnace having a conventional thermostat control arranged to turn the furnace burner on and off. Circuit means are arranged to override the thermostat to turn the burner off when the temperature of the flue gases leaving the furnace are above a first level and to hold the burner inactive until the flue temperature drops to a second lower level. A bypass circuit is also provided to hold the burner in operation anytime conditioned air returned to the furnace from the comfort zone falls below a predetermined temperature.

Abstract: A method of maximizing available but unused heated air located in the plenum of a furnace which comprises sensing the point at which air within the furnace plenum is sufficiently warm to provide valuable hot air but is still below the activation temperature of the furnace blower and displacing said warmed air into the air flow paths for a room air space, and continuing said displacement after the furnace blower has shut down until the air within the plenum reaches the point at which it no longer has valuable heating capacity. The device is a heat sensitive thermostatically controlled unit which comprises a small horsepower, low energy consumption air displacement motor. Associated therewith is an air deflector for directing displaced air into the air paths for a room air space and also associated therewith is an air temperature sensing switching means for stopping and starting the motor in response to sensed temperatures within the plenum of a furnace.

Abstract: A solar heat augmented heating system is disclosed in which a solar heat chamber located in an attic is employed selectively to supply heat to the heating system which heats the occupant space, thereby to decrease the load on the conventional heating system. This system is integrated with an improved form of automatically controlled gable vent.

Abstract: The flue pipe for a combustion chamber of a hot air furnace passes through the hot air plenum and then passes through the cold air supply duct. Heat exchange fins are secured to a length of the flue pipe located within the hot air plenum and within the cold air supply duct to utilize the residual heat of the flue gases to heat the air flowing around the fins. The flue pipe extends to a chimney for exhausting the gases. A sensor is located for response to the temperature of the air heated by both the flue pipe passing through the hot air distribution header and the furnace itself for energizing a driven blower. A thermostat produces a command signal to deliver fuel to the furnace burners. The blower is energized when the temperature in the hot air plenum reaches a predetermined level.

Abstract: An apparatus for starting a hot air recirculating furnace system. Reduced power is applied to the motor which drives the recirculating fan to cause the motor to turn at a reduced speed. The furnace is ignited during the application of the reduced power to the motor. As the temperature in the furnace increases, the warmer air recirculates and the load on the fan decreases. The power supplied to the fan motor is then increased, thereby increasing its speed as a function of the increased temperature as sensed by a thermostat in the furnace system. Full power is applied to the fan motor when the sensed temperature reaches a selected desired maximum. The apparatus and the method eliminate squeal of the belt which drives the fan and reduce wear common to those techniques which apply full voltage to the recirculating fan at furnace start-up.

Abstract: A high energy saving heat exchanger is provided for the hot exhaust gases of a furnace which has a combustion chamber, a burner with electrical controls, a furnace heat exchanger and an exhaust pipe adapted for connection with a stack. The high energy saving heat exchanger includes a housing having an air chamber with an exhaust inlet connected to said furnace exhaust pipe and an exhaust outlet. An exhaust conduit interconnects said housing exhaust outlet and stack. A continuous circuitous tubing is nested within the air chamber of said housing at one end connected to said exhaust inlet and at its other end connected to said exhaust outlet. An exhaust fan is interposed in said exhaust conduit for drawing exhaust gases through said heat exchanger tubing and delivering said gases under pressure to said stack. A hot air duct is interposed between said housing and a floor surface defining an area to be heated and including a hot air register. Heat duct communicates with said air chamber.

Abstract: An electrical circuit having three states depending upon the magnitude of an electrical signal coupled, in operation, to an input thereof, the circuit having a first stable state when the said magnitude is less than a first, predetermined value, a second, stable state when the said magnitude is greater than a second, predetermined value higher than the first said predetermined value, and a third, unstable state when said magnitude is equal to or between said first and second predetermined values. In a development of the invention, the circuit is incorporated in a control apparatus for a ducted, warm-air, central-heating system in which the gas supply to a burner is supplied continuously when the temperature of a space to be heated is below a predetermined temperature, is cut-off when the temperature of the space is above another, higher predetermined temperature, and is switched on and off at a rate dependent upon the magnitude of the temperature when it is equal to or between the two values.

Abstract: Test apparatus is disclosed for testing a gas-fired forced air heating system having a plurality of control elements. A monitoring device includes an indicator light adjacent to the thermostat for indicating a malfunction in the heating system, the monitoring device including condition-responsive switches for energizing the indicator in response to the absence of a stream of heated air when called for by the thermostat or in response to a malfunction in the thermostat. An analyzer comprises a plurality of indicator lights connectable through a selector switch to the power source and the heating system, the switch having an "OFF" condition for disconnecting the indicator lights, a "TEST" condition for checking the condition of the indicator lights and an "ON" condition for connecting the indicator lights respectively in parallel with corresponding heating system control elements to test the conditions thereof. Two embodiments of the analyzer are disclosed for use with different types of heating systems.

Abstract: A heating apparatus has a firebox, ash pit and flue enclosed in a casing wherein the fire is maintained toward the rear of the firebox and the ash pit is positioned at the front and below the firebox. The flue connects to a rear portion of the firebox and extends toward the front of the casing and then rearwardly where the fumes are exhausted to the atmosphere. Electrical controls adjustably open a vent located in the front of the ash pit to control the size of the fire by controlling the available oxygen. A fan mechanism circulates fresh air around the firebox and the flue inside the casing to provide a source of heated air for convection heating. The fan is controlled by a temperature controller to maintain the heated air within specified temperature limits.

Abstract: A forced air heating system for homes and other buildings wherein a fireplace with a circulating air heating chamber is interposed between the fan exhaust of a conventional forced air furnace and a network of air outlet registers positioned in the various rooms to be heated. A bypass air duct is positioned in parallel with the fireplace between the fan exhaust and the network of outlet registers to provide an alternate path for the forced air exhausted from the furnace fan. The system has a control circuit sensitive to room temperature, fireplace heating chamber temperature, and other duct temperatures for automatically operating the system either in a primary mode wherein the fireplace is the primary forced air heating source, or in a secondary mode where the furnace heating elements are the primary heat source. Automatically controlled dampers determine through which of the two parallel ducts the forced air from the furnace fan will travel to the outlet registers, dependent on the mode of operation.

Abstract: A furnace and method of operation are disclosed for the efficient, controlled combustion of a combustible material such as wood, coal, etc. The furnace includes a grate which grate permits a large amount of combustible material to be stacked within the grate and to be constantly compressed to insure efficient combustion. The furnace also includes a heat exchanger surrounding the grate, which heat exchanger is comprised of an intake jacket and an exhaust jacket disposed on opposite sidewalls of the furnace. The heat exchanger also includes a plurality of heat exchange tubes disposed above and behind the grate and connecting the jackets. Air is drawn into one of the jackets, is directed through the heat exchange tube where the air is heated, and is exhausted through the other jacket. A portion of the heat exchanger intake air is diverted through a perforated air delivery tube disposed adjacent to the grate to provide combustion air for the combustible material.

Abstract: This invention is comprised of a thermostatically controlled safety circuit and device used in conventional hot air oil burning furnaces which automatically turns the oil burner off when the temperature of the room heated by the furnace becomes abnormally hot. By so doing an overheated furnace and possible fire is avoided. The invention is comprised of a line voltage or safety thermostat positioned at or near the location of the conventional furnace thermostat. The line voltage thermostat is connected between the limit switch and the control circuit of the furnace control circuit. A variation of the invention is comprised of the line voltage thermostat or safety thermostat connected or ganged with the conventional furnace thermostat so that the line voltage thermostat will be activated at a higher temperature than the conventional thermostat.