Abstract: When an output from a sensor (11) is decreased below a key-lock release preset value (K), a comparator (19) generates an output so as to reset a flip-flop (21) and to enable an AND gate (22). When the output from the sensor (11) is decreased below a reset preset value (R), a comparator (20) generates an output so as to supply a reset signal to an integrated value holding unit (16) through the AND gate (22) and to reset the flip-flop (21), thus thereafter restarting an integral action by the integrated value holding unit (16).

Abstract: A regulating arrangement intended for supplying heat to a confined space, including a heating source (13), a regulating means (12) intended for regulated heat supply from the heating source, a device for detecting one or a plurality of measurement values and connected (12a, 12b) to the regulating means, which in dependence on received measurement values regulates the amount of heat delivered by the heating source. The regulating means (12) is controlled (10b) by a device arranged to detect the actual heating requirement of the ventilation air at that moment in time, or for detecting a part of this heat requirement.There is also provided an arrangement or a device for establishing when the requirement to heat an air mass to achieve a pre-determined temperature increase exceeds a pre-determined heating requirement and by how much, by causing the air mass an energy delivering means (4) and establishing the energy taken-up by the air mass and the heat content of the mass at that moment in time.

Abstract: An auxiliary heating/cooling system controller is connected in series between the household thermostat and the furnace burner valve and compressor. The controller includes a timing control which is responsive to a preset time interval valve and the plenum temperature to cycle the furnace burner on and off in order to moderate the temperature of the furnace heat exchanger, thus improving furnace efficiency. Upon installation the controller is programmed with a digital valve corresponding to the delay between a call for heat from the household thermostat and the initiation of the furnace fan. This value is then used to set a timer in the controller which synchronizes the initiation of the duty cycle control of the burner to the start of the fan at the beginning of a heating cycle, and to control the cycle time of the burner. A plenum thermostat monitors the temperature of the air produced by the furnace and if the air exceeds a predetermined limit the OFF time of the burner is increased.

Abstract: A temperature sensitive duty cycling control switch is mounted to a forced air ductless gas or oil heater by a special mounting bracket. The bracket attaches to the front of the heater in the path of the heated airflow. The mounting device is basically a tapered conduit or duct which is held at a distance from the heater so that it does not unduly obstruct the airflow and is tapered to concentrate air generated by the heater onto a plate mounted in front of the duct. The duty cycling control switch is then mounted to this plate and responds to the temperature of the plate. This enables the cycling of the heater burner while the fan continues to operate.

Abstract: Damper means having rotatable closure means mounted in a housing placed in the flow stream of a heating/cooling medium to regulate and control the medium being transported through duct means of a heating/cooling device; said closure means being operated by motor means, said motor means and fuel control means of the heating/cooling device being energized by means of a coded signal of thermostatically operated generator/transmitter means, said signal being transmitted along existing wires of a structure to receiver means, said receiver means electrically connecting to said motor means and to fuel control means, demodulating said coded signal and operating said motor means and fuel control means.

Abstract: An adaptive microprocessor control system and method provide a low heat mode and a high heat mode of a heating cycle in a furnace dependent upon the performance of the previous heating cycle. The duration of the low heat mode and subsequent high heat mode period is a function of the previous low heat mode duration, previous high heat mode duration, and the time period between the end of the previous heating cycle and the beginning of the next heating cycle. The control and method utilize a single-stage thermostat for providing the dual rates of heating.

Abstract: An electronic thermostat utilizing a switched power supply which operates either from a voltage appearing across an open circuit at a heater or air conditioner activation circuit (de-energized state) or from a current flowing in the activation circuit upon short circuiting (energized state) of the activation circuit. The power supply provides an uninterrupted source of power to the electronic thermostat which controls the source of input power to the power supply in addition to the state of the activation circuit. The electronic circuit implements a piecewise linear, with hysteresis loop discontinuity, control function.

Abstract: A device for augmenting the control of a forced air furnace includes a heat probe which is located in association with a furnace heat exchanger so as to sense the air temperature of air passing across the heat exchanger. The probe is connected via a buffer to an optical controlled switch. A latch is associated with both the probe and the switch such that in response to a high temperature turn off point the optical coupled switch shuts off the furnace solenoid associated with the furnace and maintains the solenoid in an off position until the probe senses a low temperature turn on point. Upon sensing the low temperature turn on point the solenoid is turned back on and is maintained in the on position by the latch until the high temperature point is again reached.

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: A flue gas heat recovery apparatus for a forced air type furnace of the type having a furnace heat exchanger, a return air duct and a heated air duct, and a blower for passing air from the return air duct over the furnace heat exchanger to the heated air duct. The heat recovery apparatus includes a secondary heat exchanger mounted in the return air duct having its inlet connected to the outlet of the furnace heat exchanger and an induced draft fan having its inlet connected to the outlet of the secondary heat exchanger and its outlet connected through an outlet flue pipe to the chimney. A vane is mounted in the outlet flue pipe in the path of flow from the induced draft fan and is moved between a closed position when the fan is not operating, to an open position when the fan is operating, and a switch is operated by the vane to operate the burner control after the induced draft is in operation.

Abstract: A home heating system which transfers heat generated in a fireplace, throughout the home using the duct work and furnace fan already installed in a home, having a natural gas fired forced air furnace; said home heating system being an inexpensive, simple closed loop system compatible with the existing forced air furnace heating system. The home heating system having a hydro-grate through which a heat transfer fluid flows, said hydro-grate being placed in the fireplace and the fire in the fireplace heating the heat transfer fluid. The home heating system then pumping the hot heat transfer fluid to cooling radiators which are placed in the cold air plenum of the forced air furnace, and the forced air furnace fan being automatically activated. The electrical circuitry of the activating mechanism of the furnace fan being in parallel with the existing temperature activation of the furnace fan, thus the operation of the forced air furnace is in no way affected.

Abstract: A hot water heating system wherein an air-to-water heat exchanger is attached to the outside of a jacketed space heater, and a fan draws hot air through an opening in the jacket and downward through the heat exchanger.

Abstract: An integrated control system for a temperature conditioning apparatus which contains a microprocessor which is connected to the various components of a control system of the temperature conditioning apparatus such as the space thermostat, the fuel valve, the fuel igniter and ignition proving apparatus, the stack temperature sensor, the ambient or vestibule temperature sensor, the plenum temperature sensor, the induced draft blower motor, the refrigeration compressor, and the air circulating fan or blower. With the microprocessor, which has the capability of fast and many types of operations, the interaction of parameters of the temperature conditioning apparatus and operation of the various components of the system can be controlled in an improved manner to add to the overall efficiency of such a temperature conditioning apparatus.

Abstract: The heat exchanger of the temperature control system for a vehicle passenger compartment exchanges heat with air entering the passenger compartment. The flow of heat-exchange medium through the heat exchanger is controllable for controlling passenger-compartment temperature. A servo comparator receives and compares a temperature command signal and a feedback signal and produces an error signal which operates an actuator which in turn actuates an adjuster for fluid flow through the heat exchanger. The command signal is derived from a command transducer whose setting is adjustable by a passenger. The feedback signal is derived from a passenger-compartment temperature sensor but additionally, in order to avoid system instability, is furthermore derived from a heat-exchanger temperature sensor. In particular, the feedback signal includes a component whose value is determined by the rate of change with respect to time of the temperature sensed by the heat-exchanger temperature sensor.

Abstract: A heating system for an inhabitable enclosure having a first heating system that maintains a first temperature in the absence of persons in the enclosure and a second heating system that maintains a second elevated temperature using outside fresh air with control means to detect the presence of a person in the enclosure to energize the second system.

Abstract: A flue gas heat recovery apparatus is employed with a system of appliances such as a gas furnace and hot water heater, each having separate exhaust gas flues. The apparatus includes a gas-to-liquid heat exchanger in thermal communication with the two flues to simultaneously extract heat therefrom and a liquid-to-gas heat exchanger disposed within the furnace cold air return duct. A pump circulates water between the exchangers in response to a control signal to employ the recovered heat to preheat the cold air entering the furnace through the cold air return duct. A hysteretic control circuit monitors exhaust gas temperature and provides for system operation between high and low gas temperature limits. In the preferred embodiment of the invention, a furnace blower override feature is employed to energize the blower during periods of pump operation.

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: Thermostatically controlled valves and acoustic transducers are energized by thermostats in individual zoned heated areas of a structure. The thermostatic valves or dampers permit heated fluid to convey heat to their respective zoned heated areas and the acoustic transducer couples an acoustic signal to a feed or return duct or line. The acoustic signal is transmitted on the duct or line to an acoustic receiver in the vicinity of the furnace which, upon receiving the acoustic signal transduces the acoustic signal to an electric signal which is effective to control a controller. In one embodiment of the invention, periodic listening pulses are employed in the operation of the furnace and/or circulator to avoid interference with the communication system due to noise of these components.

Abstract: An integrated control system for a temperature conditioning apparatus which contains a microprocessor which is connected to the various components of a control system of the temperature conditioning apparatus such as the space thermostat, the fuel valve, the fuel igniter and ignition proving apparatus, the plenum temperature sensor, the induced draft blower motor, refrigeration compressor and coil temperature sensor, and the air circulating fan. With the microprocessor, which has the capability of fast and many types of operations, the interaction of parameters of the temperature conditioning apparatus and operation of the various components of the system can be controlled in an improved manner to add to the overall efficiency of such a temperature conditioning apparatus.

Abstract: A circulating fluid that is heated by a number of gas-fired burner assemblies is used to heat a space either through a hot water system or a forced air heating system. Each burner assembly includes a housing with a heat exchanger mounted therein and a gas burner for heating the fluid which flows through the heat exchanger. The heat exchangers are connected in parallel in a closed loop forced circulation system. A microprocessor based thermostat control compares the temperature in the space heated by the air with a reference temperature. Dependent upon the magnitude of the difference between the temperatures, one or more of the burner assemblies are energized. The burner assemblies are sized such that during most of the heating season only a fraction of the burner assemblies are used.

Abstract: A flue gas heat recovery system includes a heat exchanger fluidly interposed between a furnace and a chimney to receive hot flue gas from the furnace. The heat exchanger is releasably mounted in the chimney and includes a partition which forces air being heated by the heat exchanger to traverse a path through the heat exchanger which maximizes the time of contact between that air and the heat exchanger heating elements. The partition further creates turbulence in the heat air.

Abstract: Efficiency of domestic heating systems is improved by a flue temperature responsive switch for intermittently shutting down the burner when temperature conditions are such as would cause extended operation of the burner in the absence of the switch. The temperature at which shut-down occurs is adjustable, and the temperature at which burner operation is reestablished is dependent on the shut-down temperature. However, the minimum temperature at which burner operation is reestablished by the switch is fixed at the time of installation of the switch by securing a control knob having a stop at a selected position on a control shaft which adjusts the shut-down temperature. The switch contacts are constructed so that the switch closes if any of its principal movable parts fail.

Abstract: A thermostat controlled window furnace for heating a room features a construction wherein the air required for its operation is comprised on the one hand of outside air used solely for combustion purposes, to service a heat transfer component, and on the other hand of air drawn from the room, to be heated in passage through the heat transfer unit and returned to the room to elevate its temperature. The arrangement provided for inflow of room air insures that it will exhibit the general temperature of the room. The furnace not only provides for an effective separation therein of outside air and room air which is utilized thereby but for a return to the room of heated air in a manner to inhibit a chance or premature intermingling thereof with that portion of the room air being drawn into the furnace the function of which, in part, is to signal the general temperature of the room to a furnace thermostat.

Abstract: An improved fan controller for forced-air temperature conditioning apparatus for buildings, such as for example, forced warm air furnaces in which the fan turn-off is controlled as a function of the difference in temperature between the plenum temperature and the return air temperature.

Abstract: This invention pertains to apparatus and a method for utilizing waste heat as produced in furnaces, particularly boilers. This apparatus and method is equally useful in hot air furnaces. After heating the water or air the heat that passes into the plenum is caused to pass over and around a heat exchanger which moves air by a blower means through this exchanger into the house or basement. This air can be humidified, if desired. The exhaust stack during the combustion period is open to the chimney. At other times it is closed to prevent heat escape from the boiler. A collecting means is provided for moisture that may collect on the heat exchanger.

Abstract: A solid fuel burning heater has an inner combustion chamber housing enclosed within an outer housing with a fuel feed door in the inner combustion chamber housing being aligned with an outer housing door; an air inlet in the bottom of the combustion chamber housing has a thermostatically controlled air inflow closure valving member connected to a wire bail having an upper end encircling a cam rod connected to the outer housing door. Opening movement of the outer housing door moves the cam rod so that the air inflow closure valving member is opened to provide combustion air into the combustion chamber and prevent blowback upon the subsequent opening of the fuel feed door.