Abstract: A locally powered intermittent pilot combustion controller may include an igniter, a thermal electric and/or photoelectric device that produces an electrical signal having power when exposed to a flame, and a local power source for providing power when the thermal electric and/or photoelectric device is not exposed to a flame. In some cases, the intermittent pilot combustion controller may include a memory for storing information about an ignition sequence for igniting a pilot flame, and a controller coupled to the memory. The controller may be configured to initiate the ignition sequence of the pilot flame using information stored in the memory, determine whether the ignition was successful by monitoring the electrical signal produced by the thermal electric and/or photoelectric device, and adjust the information stored in the memory based on whether the ignition sequence completed successfully.

Abstract: There is described a system and method of a building management system for preventive maintenance of an HVAC unit. Runtime data of the HVAC unit is received at a control system remote from the HVAC unit. A service message is initiated, by the control system, to a service device associated with the HVAC unit in response to determining that a preventive maintenance visit is warranted based on the runtime data. A hot-cold test for the HVAC unit is activated by the control system in response to receiving the registration message of the preventive maintenance visit from the service device. A validation message is reported in response to validating the preventive maintenance visit based on a result of the hot-cold test for the HVAC unit.

Abstract: A flame detection system includes: an optical sensor that detects light generated from a light source; an applied voltage generating circuit that periodically applies a drive pulse voltage to the optical sensor, discharge determining portion that detects a discharge from the optical sensor, a discharge probability calculating portion that calculates a discharge probability based on a number of times of application of the drive pulse voltage and a number of times of discharge detected in the a first state in which the optical sensor is shielded from light and a second state in which the optical sensor can receive light, a sensitivity parameter storing portion storing known sensitivity parameters of the optical sensor; and a received light quantity calculating portion that calculates the received light quantity by the optical sensor in the second state based on the sensitivity parameters and the discharge probabilities calculated in the first and second states.

Abstract: Burner (10), in particular for a vehicle heater (12), having an orifice plate (14) separating an inner combustion region (16) from an outer region (18), wherein a photosensitive sensor (20) is arranged in the outer region (18), wherein at least two separate air inlet openings (22, 24, 26, 28) are being provided in the orifice plate (14), wherein one of the at least two air inlet openings (22, 24, 26, 28) is additionally formed as a light opening (28) which also allows light to pass from the inner combustion region (16) to the photosensitive sensor (20) that is arranged in the outer region (18), wherein the at least two air inlet openings (22, 24, 26, 28) are being shaped such that the same combustion air quantities flow into the internal combustion region (16) per unit time, respectively, and wherein the orifice plate (14) is transparent and/or the light opening (28) has a shape different from the air inlet openings (22, 24, 26) that are not formed as light opening such that an illumination area defined by th

Abstract: A sanitary washing device according to an embodiment comprises a heating part, a nozzle configured to jet water heated by the heating part toward human private parts; a controlling part configured to control at least one of the heating part and the nozzle, and a monitoring part. The monitoring part is configured to diagnose a failure of the controlling part and to prohibit at least one of heating in the heating part and jetting from the nozzle when the controlling part fails. The controlling part is configured to diagnose a failure of the monitoring part and to prohibit at least one of heating in the heating part and jetting from the nozzle when the monitoring part fails.

Abstract: A heat pump system includes a compressor, usage side heat exchanger, heat source side heat exchanger, expansion mechanism, main refrigerant flow control device switchable between cooling and heating modes, gas reheat heat exchanger connected in the refrigerant circuit, a fan disposed to direct an airflow across the usage side heat exchanger and the gas reheat heat exchanger into a target space, and a secondary refrigerant flow control device switchable between first and second modes. Refrigerant flows from the discharge line to the main refrigerant flow control device in the heating mode and the cooling mode in the first mode. Refrigerant flows from the discharge line to the gas reheat heat exchanger in a gas reheat mode and then flows to the main refrigerant flow control device in the second mode. A flow of the heat transfer medium to the heat source side heat exchanger is adjustable.

Abstract: A control system for controlling a gas powered appliance includes a hot surface igniter, an igniter relay, and an integrity detection circuit. The integrity detection circuit is configured to be coupled to a power source, the igniter relay, and the hot surface igniter to produce an output indicative of the integrity of the hot surface igniter and the igniter relay. The integrity detection circuit is configured to output a first voltage when the igniter relay is closed and output a second voltage different from the first voltage when the hot surface igniter is in a non-short circuit failure condition.

Abstract: A combustible fuel burner system includes a burner unit, a power source, and a circuit interrupter unit. The circuit interrupter unit has a switch electrically coupled between the power source and the burner unit. The switch has a closed state, wherein the burner unit receives operational electrical power from the power source. The switch moves from a closed state to an open state and electrically disconnects the device from the power source upon a voltage of the power source falling below an interruption threshold. The switch, when in the open state, moves to the closed state upon the voltage of the power source being above a restoration threshold that is higher than the interruption threshold.

Abstract: A monitoring device has a first flame detector, to receive a first batch of radiation, which is emitted by the first flame, a second flame detector, to receive a second batch of radiation, which is emitted by the second flame, a voltage supplying device to apply an alternating voltage with a first half wave and a second half wave to the two flame detectors and an evaluation circuit that is connected to the two flame detectors via a signal input. A first measurement signal that is present at the common signal input during the first half wave is indicative of the intensity of the first batch of radiation. A second measurement signal that is present at the common signal input during the second half wave is indicative of the intensity of the second batch of radiation. The evaluation circuit independently evaluates the first measurement signal and the second measurement signal.

Abstract: A service method of gas appliances includes: Detecting the gas appliances at the client ends to generate detecting signals. Transmitting the detecting signals to a service end. Identifying which client end the detecting signals come from. Examining the detecting signals to find whether the gas appliance has an abnormal condition; and informing the client end when the abnormal condition is found. After all, the service end may monitor the gas appliances at the client end, and inform the client for repair when the gas appliance has detected an abnormal signal or has damaged parts.

Abstract: A system for providing a combined water and fire display is provided. More specifically, a decorative display comprises a dynamic water and fire display device where fuel/air, water, and fire are integrated. The decorative display provides for unique aesthetic qualities and an appearance wherein flames are positioned at or near the surface of a volume of water. In various embodiments, the decorative display further comprises various safety features including the ability to detect and self-regulate conditions such as the existence and/or absence of a pilot flame, an adequate amount of water, and the temperature of various portions of the system. The decorative display further contemplates the ability to operate without one or more disclosed features, such as when only a water display or only a fire display is desired.

Abstract: A service method of gas appliances includes: Detecting the gas appliances at the client ends to generate detecting signals. Transmitting the detecting signals to a service end. Identifying which client end the detecting signals come from. Examining the detecting signals to find whether the gas appliance has an abnormal condition; and informing the client end when the abnormal condition is found. After all, the service end may monitor the gas appliances at the client end, and inform the client for repair when the gas appliance has detected an abnormal signal or has damaged parts.

Abstract: An ignitor spark indicator 100 is described that monitors RF signals within a flame rod 25 located near a spark rod 23. The signal from the flame rod 25 is processed to provide a waveform that indicates when electrical arcing is occurring. The indication when arcing is occurring is also provided to flame-detecting equipment. The flame-proving device 60 only operates when the arcing is not produced so that the flame-detecting device 60 does not confuse the arcing with a flame reducing the false positive determinations.

Abstract: Exemplary embodiments are disclosed of a climate control system that includes an igniter and a controller having an igniter relay. The controller senses a current level through the igniter and senses voltage between terminals of a second relay of the controller. In a given one of a plurality of operational phases of the system, the controller is configured to compare the sensed current level and sensed voltage to a current level and voltage associated with a specific condition of the igniter, igniter relay, or second relay in the given phase. Based on a result of the comparing, the controller is configured to distinguish between a failure of one of the relays and a failure of the igniter.

Abstract: A flame sensing system having a flame rod, a signal generator, a signal measurement circuit, and a controller, where the frequency and/or amplitude of the excitation signal may be variable. The signal measurement circuit may include a bias circuitry that references the flame signal to a voltage, a capacitor that varies the filtration, an AC coupling capacitor, a current limiting resistor, and a low-pass filter. The system may determine the flame-sensing rod contamination, the stray capacitance of the flame sensing system, and compensate for stray capacitance in the flame sensing system. The flame model may include a circuit that simulates a flame in the presence of the sensing rod, and another circuit that simulates a contact surface between the flame and the sensing rod.

Abstract: A control system for a fuel-fired appliance and methods of operating are disclosed. In an illustrative embodiment, when an electrical characteristic of an optical detector, such as a resistance, does not change by at least a predetermined amount during an ignition trial, and/or when a level of EMI or electrical noise detected by an antenna in a burner assembly of the fuel-fired appliance does not increase during the ignition trial, the control system may determine that the ignition assembly is not sparking properly. In some instances, the control system may also be programmed to activate an indicator that would indicate to a user or technician a potential problem with the ignition assembly (e.g. not sparking properly to ignite fuel).

Abstract: The disclosure relates to a process of configuring a standalone self-supplied numeric controlled relay for providing phase and earth over current protection to electrical systems by accurate current measurement. The arrangement for current measurement with control algorithms is provided for power control by providing amplified and conditioned current for optimization between the current to power an electronic circuit and the fidelity of a measured current waveform so that they both are at the acceptable levels at the same time. This disclosure describes the current sensing and associated algorithm for power control in a truly self-powered relay.

Abstract: A system for providing a combined water and fire display is provided. More specifically, a decorative display comprises a dynamic water and fire display device where fuel/air, water, and fire are integrated. The decorative display provides for unique aesthetic qualities and an appearance wherein flames are positioned at or near the surface of a volume of water. In various embodiments, the decorative display further comprises various safety features including the ability to detect and self-regulate conditions such as the existence and/or absence of a pilot flame, an adequate amount of water, and the temperature of various portions of the system. The decorative display further contemplates the ability to operate without one or more disclosed features, such as when only a water display or only a fire display is desired.

Abstract: A service method of gas appliances includes: Detecting the gas appliances at the client ends to generate detecting signals. Transmitting the detecting signals to a service end. Identifying which client end the detecting signals come from. Examining the detecting signals to find whether the gas appliance has an abnormal condition; and informing the client end when the abnormal condition is found. After all, the service end may monitor the gas appliances at the client end, and inform the client for repair when the gas appliance has detected an abnormal signal or has damaged parts.

Abstract: A system of detection and analysis of gas or fuel oil flames using optical devices, consisting of a sensor that targets the flame's reaction zone through an optical access, a processing and control module, and an actuator, responsible for controlling the damper. The system optimizes combustion equipment operation by controlling the damper, obtaining better performance and reducing polluting emissions.

Abstract: A signal generation system for flame ignition and sensing. The ignition signal generation is adaptive for improving flame ignition while eliminating excess energy usage. High voltage signals for flame sensing may also be provided. If more energy or speed is needed for ignition signal generation, then the flame sensing signal generation portion may be disabled to increase the amount of available energy. Adaptation for ignition signal generation may be guided by the results of flame sensing. The flame sensing voltage may be regulated based on the flame current strength. The flame current may be controlled within an optimum range to reduce rod contamination rate and yet provide reliable flame sensing when the rod contamination built up. The adaptation may be algorithmic-based with the facilitation of a microcontroller. The system may provide the high voltage signals from a low voltage power supply, such as that of 24 VAC.

Abstract: A time-varying voltage is applied to an electrode, or a pair of electrodes, of a sensor installed in a fuel nozzle disposed adjacent the combustion zone of a continuous combustion system, such as of the gas turbine engine type. The time-varying voltage induces a time-varying current in the flame which is measured and used to determine flame capacitance using AC electrical circuit analysis. Flame capacitance is used to accurately determine the position of the flame from the sensor and the fuel/air ratio. The fuel and/or air flow rate (s) is/are then adjusted to provide reduced flame instability problems such as flashback, combustion dynamics and lean blowout, as well as reduced emissions. The time-varying voltage may be an alternating voltage and the time-varying current may be an alternating current.

Abstract: A control apparatus for a gas-fired heating appliance having a burner is provided for sensing burner flame instability. The apparatus includes a sensor for sensing a flame and providing an output of a flame current signal, and a controller in communication with the sensor for sensing flame current. The controller is configured to receive the flame current signal and to detect the occurrence of a flame instability condition. The controller detects flame instability from flame current signal data that is measured and Fourier transformed into a frequency spectrum which changes from a stable to instable spectrum when flame instability is caused by an inadequate air-to-fuel ratio. The controller is configured to respond to flame instability by generating an output signal to increase the speed of a combustion air blower that supplies air to the burner, to thereby increase the air flow relative to fuel flow until normal combustion is attained.

Abstract: A system for adjusting a bias voltage of a flame sensing system. The system may use pulse width modulation to adjust the bias voltage. The system may have a flame sensing rod that conveys an electrical equivalent circuit of a flame presence to a detector via low pass filter. An excitation voltage may be conveyed via a DC blocking mechanism to the sensing rod. A pulse width modulation signal may be conveyed via a bias resistor to a node of the low pass filter and the detector. The input of an A/D converter may be that of the detector for flame signals. Also, leakages between the node of the A/D converter connection and the voltage source and/or ground may be detected and compensated. Further, leakage of the DC blocking mechanism may be minimized.

Abstract: A flame sensing system having a flame rod, a signal generator, a signal measurement circuit, and a controller, where the frequency and/or amplitude of the excitation signal may be variable. The signal measurement circuit may include a bias circuitry that references the flame signal to a voltage, a capacitor that varies the filtration, an AC coupling capacitor, a current limiting resistor, and a low-pass filter. The system may determine the flame-sensing rod contamination, the stray capacitance of the flame sensing system, and compensate for stray capacitance in the flame sensing system. The flame model may include a circuit that simulates a flame in the presence of the sensing rod, and another circuit that simulates a contact surface between the flame and the sensing rod.

Abstract: A method and an apparatus for operating a gas-powered cooking device including an actuator for moving a closure disposed in the gas feed conduit of a burner to an open state and of igniting gas emitted from the burner by an ignition electrode to form a burner flame, the ignition electrode being connected to an ignition voltage for a predetermined first interval of time, a sensor thermo-conductively connected to the burner flame for generating a sensor voltage for maintaining the closure means in its open state if the sensor voltage attains a predetermined level and of initiating subsequent ignitions after a predetermined interval of time where the predetermined level is not attained within a predetermined further interval of time.

Abstract: A flame sensor apparatus for use with a flame heated thermal abatement reactor is provided, including a flame sensor adapted to sense a flame within the thermal abatement reactor; and a shutter adapted to selectively block the transmission of radiation from the flame to the flame sensor.

Abstract: A cooking stove that prevents the execution of a process such as ignition of a burner when a touch switch changes from a non-sensing state to a sensing state. In STEP201, when a first touch switch, which is one of the touch switches provided in an operation, is turned on from off, the process advances to STEP202, where a controller provided in a cooking stove main body starts a 1-second timer. The controller executes a loop composed of STEP203 and STEP210. When a second touch switch, which is one of the touch switches and is different from the first touch switch, is turned on from off in STEP210 before the 1-second timer times up in STEP203, the process advances from STEP210 to STEP211. The controller performs “error reporting” by blinking a display portion and activating a buzzer.

Abstract: A cooking stove that prevents a burner from being ignited when a touch switch shifts from a non-sensing to a sensing state. An operation portion having a touch switch is provided on a glass top plate of a cooking stove main body which accommodates burners. The touch switch allowing a user to give instruction on actuation and stoppage of the burners and sensing an object that contacts or approaches the top surface of the glass to plate. Heating control means for determining whether the touch switch is on (a sensing state) or off (a non-sensing state) to control actuation of the heating means. While the burner is at a stop, when the touch switch is turned on and then off again, the heating control means ignites the burner. While the burner is in operation, when the touch switch is turned on, the heating control means extinguishes the burner.

Abstract: A heat pump type heating and air conditioning system includes a gas furnace or other auxiliary heat source and a thermostat and controller associated with the heat pump and the auxiliary heat source for automatically energizing the heat pump if the auxiliary heat source is inoperative regardless of whether or not the automatic heating mode has been selected or the auxiliary heating mode has been selected by the user of the system. A method of operating a heat pump system with an auxiliary heating source to automatically change from operation of the heat pump to the auxiliary heating source depending on conditions such as outdoor temperature, and to automatically change back to operation of the heat pump if the auxiliary heating source is inoperable.

Abstract: A touch switch which prohibits a child from actuating heating means, while permitting a child to deactivate heating means. A cooking stove including an electrical capacitance operation switch 10 which switches the cooking stove between an operation state in which an ignition instruction is enabled and a standby state in which the ignition instruction is disabled; the operation switch is used to instruct the cooking stove to be extinguished. When the cooking stove is inactive, a switch circuit 63 selects a resistance element 61 offering a higher resistance to set the cooking stove in a “lower sensitivity set state” in which the operation switch 10 has a sensitivity sl. When the cooking stove is active, the switch circuit 63 selects a resistance element 62 offering a lower resistance to set the cooking stove in a “higher sensitivity set state” in which the operation switch 10 has a sensitivity sh (>sl).

Abstract: A method of verifying proper operation of an electromagnetic valve. The method includes providing a mechanism to effect opening of the valve, verifying that the valve opened as a result of employing the mechanism to effect opening of the valve and after verifying the valve opened, signaling the valve to close after a first period of time has elapsed. The method further includes, after signaling the valve to close, signaling the valve to re-open after a second period of time has elapsed and detecting the occurrence or non-occurrence of an event associated with the closing or re-opening of the valve.

Abstract: The present invention is directed at systems and methods for detecting flue blockages in an HVAC system without the addition of numerous additional sensor elements, wiring, and connections that can unduly increase the cost and possibly reduce the reliability of the HVAC system. In an illustrative embodiment of the present invention, changes in the output of a flame sensor are used to detect when a likely flue blockage exists.

Abstract: A modulating gas burner control system using closed loop feedback from a flame rod which provides a signal that varies with gas pressure and which provides combustion air fan control to accurately control the heat from the system without use of expensive control valves.

Abstract: A control device for controlling hydrogen flow of a hydrogen storage canister accommodated in a canister containing chamber includes a heating device which is connected to a heating fuel storage tank via a heating fuel supplying pipeline for conveying a heating fuel to a catalyst bed in the canister containing chamber and generating heat by combustion of the heating fuel at the catalyst bed. A blowing device provides an air flow to the canister containing chamber. A controller controls the operation of the heating device and the blowing device in correspondence to a temperature signal detected from an internal space of the canister containing chamber. The controller is coupled with a setting unit for setting various parameters which are stored in a parameter storage unit for controlling the controller.

Abstract: A safety device for an industrial boiler (CHA) including electromechanical relays (REn, RS), which are connected in series in order to form an electromechanical safety chain (CH1), and at least one shunt relay (RTn) which is normally open and mounted in parallel to one of the electromechanical relays (REN). The shunt relay is controlled by an automaton (AP1) so that it is closed during a time delay. The shunt relay (RTn) is provided with a contact that is connected to an electronic circuit (CEn) and said electronic circuit (CEn) opens an electromechanical relay (RS) which is mounted in series in the safety chain when the shunt relay (RTn) is closed for longer than the time delay. Given the arrangement, in the event of an automaton failure, the time delay is ensured by the electronic circuit so that a satisfactory level of safety is guaranteed in relation to the installation.

Abstract: A safety circuit 31, which compulsorily closes an on-off valve for supplying a gas to a burner when a microcomputer for performing a combustion control is in an abnormal condition, does not operate unless abnormality occurs to the microcomputer 1, and therefore even when the safety circuit 31 is out of order, an ignition operation is performed as it is. A transistor 4 is not turned off until a fixed time elapses from a start of an ignition sequence in the safety circuit 31, but the fixed time is shortened by a timer acceleration circuit 32, and if the transistor 4 is turned off by a transistor 2 being turned on, the safety circuit 31 is determined as normal, so that the normal ignition sequence is executed thereafter.

Abstract: An ignition system includes a burner, a power supply, an electrical system including a ground conductor, and an ignition module. The ignition module includes a first input, a second input, and an output. The output is operatively coupled to the burner, while one of the inputs is coupled to said ground conductor, and the other of the inputs is coupled to the power supply.

Abstract: A safety circuit 31, which compulsorily closes an on-off valve for supplying a gas to a burner when a microcomputer for performing a combustion control is in an abnormal condition, does not operate unless abnormality occurs to the microcomputer 1, and therefore even when the safety circuit 31 is out of order, an ignition operation is performed as it is. A transistor 4 is not turned off until a fixed time elapses from a start of an ignition sequence in the safety circuit 31, but the fixed time is shortened by a timer acceleration circuit 32, and if the transistor 4 is turned off by a transistor 2 being turned on, the safety circuit 31 is determined as normal, so that the normal ignition sequence is executed thereafter.

Abstract: A programmable burner for gas stoves, which is constituted by a gas burner and a safety valve that includes a thermocouple, which is located in coincidence with an external edge of the burner. The safety valve is maintained open when the thermocouple is detecting the presence of a flame on the gas burner and is closed when the burner has been turned off. An electrode is placed near of the external periphery of the burner for igniting. A spark generation module is connected with the electrode for generating the sparks for igniting the burner. A spark interrupter is connected to the spark generation module, the spark interrupter being located over a burner knob that is connected to the safety valve, for activating or deactivating the spark generation of the spark generation module. Finally a programmable device is connected with the thermocouple and the security valve, for programming the ignition time of the burner in accordance with a preestablished operation time by user.

Abstract: A conventional watchdog timer circuit is arranged to judge a microcomputer to be normal as long as a pulse signal is being outputted from the microcomputer. Therefore, an abnormal condition cannot be detected when an operating frequency of the microcomputer lowers, for example. As a solution, the watchdog timer circuit is provided with a function for detecting the frequency. If the frequency of the pulse signal deviates from a predetermined frequency range, a reset signal is outputted indicating that the microcomputer is abnormal, even if the pulse signal is being outputted. A solenoid-operated gate valve is thereby closed to stop the supply of gas to a gas burner.

Abstract: When an error occurs to a combustion device, a microcomputer inside a control apparatus for the combustion device closes a safety valve thereby stopping gas supply to a gas burner. In a conventional control apparatus, when a power source resetting is actuated with a power switch, the safety valve is opened to supply the gas burner with gas even though the cause for the error has not been resolved. As a solution, when an error occurs, the fact of such an occurrence is stored in a nonvolatile memory, i.e., electrically erasable programmable read-only memory, EEPROM. It is so arranged that, unless the reset switch is operated, the memory in the EEPROM is not reset. After resetting, the memory in the EEPROM is read out. As long as the reset has not been made, the safety valve is not opened, but the program immediately proceeds to a state in which the operation of the reset switch is held in suspension.

Abstract: A flame atmosphere analyzer is described and comprises a tube, in which an air-gas intake and mixing chamber is defined, a gas-supply nozzle, and primary combustion-air supply means opening into the intake chamber, as well as a flame burner comprising at least one flame jet which is in flow communication with the intake and mixing chamber in order to supply an air-gas mixture formed in the chamber. The primary air-supply means comprise at least one duct which has a first end in flow communication with the intake chamber and which is open at the opposite, second end in order to take in primary combustion air in a position remote and at a predetermined distance from the intake chamber in the tube. A water-heating device including the above-mentioned flame atmosphere analyzer is also described.

Abstract: A conventional watchdog timer circuit is arranged to judge a microcomputer to be normal as long as a pulse signal is being outputted from the microcomputer. Therefore, an abnormal condition cannot be detected when an operating frequency of the microcomputer lowers, for example. As a solution, the watchdog timer circuit is provided with a function for detecting the frequency. If the frequency of the pulse signal deviates from a predetermined frequency range, a reset signal is outputted indicating that the microcomputer is abnormal, even if the pulse signal is being outputted. A solenoid-operated gate valve is thereby closed to stop the supply of gas to a gas burner.

Abstract: A method and an apparatus for controlling an amount of air of a gas boiler are disclosed. Detecting section detects a flame voltage of the gas boiler to output a flame voltage value signal which represents a flame voltage value. An air supplying fan supplies air into the gas boiler. A sensing section senses a rotative velocity of the air supplying fan to output a sensing signal which represents a present rotative velocity of the air supplying fan.

Abstract: An atomic absorption photometer includes a microprocessor which is programmed so as to affirmatively create an unsafe condition by lowering the pressure inside the flow route of a combustion improving gas and to check if the gas switch in this flow route indicates this unsafe condition. If it is found that this unsafe condition is not being indicated by the switch, a warning signal is outputted and the use of flame by the photometer is prevented.

Abstract: A direct spark ignition control system is provided for controlling for a gas fireplace burner. A solenoid is operatively controlled for supplying gas to the gas fireplace burner. A high voltage spark ignition circuit is operatively controlled for generating ignition sparks near the gas fireplace burner. A flame sensing circuit coupled to the gas fireplace burner provides a feedback signal to activate and deactivate the high voltage spark ignition circuit. A timing and control circuit provides a control signal to energize the solenoid and provides a control signal to deactivate the high voltage spark ignition circuit and a control signal to deenergize the solenoid after a set time period with the burner flame feedback signal activated.

Abstract: Arrangement for interrogating multiple switch conditions employs a single input microprocessor for a plurality of switch elements that are coupled in series with an operating element and a power source. A variable oscillator has a control input and an output coupled to the microprocessor input, providing a periodic signal to the same. A plurality of impedance elements, e.g., resistors, each with a respective value, are coupled between a respective junction between two successive switch elements and the control input of said variable oscillator, such that the rate of said periodic signal varies as a function of the open or closed condition of the respective switch elements. For each switch being tested, the microprocessor looks for one predetermined frequency or pulse rate corresponding to an open condition and another corresponding to a closed condition.

Abstract: A sensor provides a status signal indicating a condition of an operating system to the operating system's control system. The sensor has an inherent variable quantity such as resistance whose magnitude indicates the operating system status. The control system includes a user-operable switch which when actuated signals the microprocessor to determine the approximate value of the sensor's variable quantity. The magnitude of the variable quantity is then indicated by a signal comprising one or more beeps of sound or flashes of light. The number of beeps or flashes indicates the approximate present magnitude of the sensor's variable quantity. In a preferred embodiment, the control system comprises a microprocessor programmed to control the operating system and to perform most of the functions of the invention.

Abstract: There is disclosed a combustion control circuit of a combustion apparatus with a driving signal generator, an exhaust fan controller and a gas valve controller, including: a combustion state detector for detecting the state of combustion occurring within a combustion chamber according to an output signal of a flame sensor installed in the combustion chamber, and for producing a signal corresponding to the state of combustion; a reference signal generator for producing a reference signal in response to each output signal of a temperature sensor and a flow sensor; a comparator for comparing the output signal of the combustion state detector with the output signal of the reference signal generator, and for outputting a signal corresponding to a difference therebetween; and an adder for adding the output signal of the comparator to the output signal of the driving signal-generator, and for respectively applying an output to each one of the exhaust fan controller and the gas valve controller.