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| Number | Title | Issue Date |
| 7913927 | Fuel economizer An electronic circuit for a hot water heating system conserves fuel consumption and reduces carbon dioxide emissions. A heating system includes a burner that heats water and a room thermostat. The electronic circuit comprises an override thermostat which has a setti... | 03/29/2011 |
| 7240851 | Thermostat fan and boiler timer A programmable timer circuit that can be connected directly to the fan switch of any thermostat with a forced air heating and/or cooling system that includes a blower fan for circulating air throughout the home. A programmable timer circuit that can be connected dir... | 07/10/2007 |
| 6637667 | Method and apparatus for energy recovery in an environmental control system Control apparatus for an environmental control system comprises input circuitry receiving environmental information and output circuitry for controlling an HVAC system. Processing circuitry in the controller configures the output circuitry based at least ... | 10/28/2003 |
| 5971284 | Apparatus for regulating heater cycles to improve forced-air heating system efficiency A method and apparatus of regulating cycles of a burner in a forced air heating system. A control unit uses a sensor at an output of a heat exchanger to make measurements of a temperature of air output from the heat exchanger. The control unit observes te... | 10/26/1999 |
| 5582233 | Air circulation enhancement system In a forced air heating and cooling system including a blower fan for circulating air in an air ambient use-space, a timer circuit and a power output control circuit for augmenting control and for regulating operation of the blower fan. The timer and asso... | 12/10/1996 |
| 5377909 | Limit switch control especially for warm air furnaces A control system to control the operation of a furnace (10) having a fuel control unit (26) to supply fuel to a burner (24) includes a limit switch (48) within furnace (10) to detect an overheated condition. The limit switch (48) opens when a reference te... | 01/03/1995 |
| 5340028 | Adaptive microprocessor control system and method for providing high and low heating modes in a furnace A method for providing a low fire mode and a high fire mode of a heating cycle in a current cycle of a furnace as a function of the previous heating cycle wherein the current heating cycle is a function exclusively of time run in low fire mode and time ru... | 08/23/1994 |
| 5337952 | Adaptive microprocessor control system and method for providing multiple heating modes in twinned furnaces In a heating system containing twinned furnaces capable of independently operating at multiple levels, a method for providing multiple heating modes to satisfy a required heating load during a given cycle, there being some total number of heating modes, w... | 08/16/1994 |
| 5326025 | Warm up method for two stage furnace A two-stage furnace is operable at a high fire full rate mode and at a low fire partial rate mode when there is a call for high heat or low heat, respectively. In order for the furnace to be less prone to vent gas condensate formation when operating at lo... | 07/05/1994 |
| 5326026 | Energy and peak-load conserving thermostat and method with controlled deadband A thermostat is disclosed for controlling a heating system, particularly a forced hot-air furnace, so as to improve fuel efficiency and decrease peak fuel load. The thermostat controls the length of fuel-on cycles, so that the heat exchanger of the furnac... | 07/05/1994 |
| 5011073 | Control to operate a forced air blower An electronic control for a warm air furnace blower including an input circuit for receiving a signal from a thermostat. The signal is delayed by a first adjustable time delay to operate a blower relay, which energizes the blower. When the input signal ce... | 04/30/1991 |
| 4951870 | Overtemperature control A blower motor failure is detected by a sensor/switch that opens at a first preset temperature level and automatically resets for the next cycle. The occurrences of such openings per thermostat cycle are counted and when they reach a predetermined number,... | 08/28/1990 |
| 4907737 | Electronic control system for a gas-fired/hot air furnace with induced draft blower Electronic control system for a gas-fired/hot air furnace includes a primary control unit which controls the flow of fuel to the furnace. The furnace has heating and cooling space thermostats and a comfort fan to supply heated or cooled air to the space b... | 03/13/1990 |
| 4838482 | Air conditioning system with periodic fan operation A temperature conditioning system has a temperature conditioning apparatus such as a heating apparatus or cooling apparatus, an air treatment for cleaning apparatus and a fan for moving air through the temperature conditioning apparatus and air treatment ... | 06/13/1989 |
| 4815524 | Control system for a furnace operating in the continuous blower mode A furnace having the capability of operating its blower continuously is provided with means for automatically shutting off the blower at the beginning of a heating cycle and for resuming the operation thereof only after a predetermined time has elapsed to... | 03/28/1989 |
| 4667874 | Energy saving furnace controller 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... | 05/26/1987 |
| 4638942 | Adaptive microprocessor control system and method for providing high and low heating modes in a furnace 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... | 01/27/1987 |
| 4595139 | Control for humidifier of the type used with thermostatically controlled furnace A control system for an electrically energized humidifier used with a hot-air furnace including an electric time-delay circuit and control means for manually adjusting the time delay. Each time the thermostat for the system energizes the furnace the humid... | 06/17/1986 |
| 4502625 | Furnace control apparatus having a circulator failure detection circuit for a downflow furnace A furnace control apparatus for a downflow forced warm air furnace uses a microprocessor and thermostat to initiate and control the start-up of the furnace. During the initial start-up operation, the microprocessor receives an input signal from the thermo... | 03/05/1985 |
| 3989928 | Method and apparatus for cyclically controlling the energization of home water heaters A method and apparatus for cyclically controlling the energization of water heaters in residential homes on a daily and seasonal temperature basis. The apparatus includes a pair of clock timers each having a disk for supporting a plurality of relay actuat... | 11/02/1976 |
| 3945564 | Temperature control system A temperature control system for providing an automatic reduction in the temperature of a room or a house during the nighttime hours which requires only the conventional two conductor wiring between the furnace and the thermostat thereby avoiding the nece... | 03/23/1976 |
