Abstract: In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. The beam from the excitation light source is split with a portion of it going to the ignitor laser and a second portion of it being recombined with the first portion after a delay before injection into the ignitor laser. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones.

Abstract: A burner apparatus is operated in a plurality of distinct modes. In a startup mode, flows of oxidant and primary fuel are ignited by an igniter and are provided simultaneously with a flow of secondary fuel until a process chamber reaches the auto-ignition temperature of the secondary fuel. In a subsequent mode, flows of oxidant and secondary fuel are provided simultaneously to the exclusion of a flow of primary fuel.

Abstract: In the apparatus of the invention, a first excitation laser or other excitation light source capable of producing alternating beams of light having different wavelengths is used in tandem with one or more ignitor lasers to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using the single remote excitation light source for pumping one or more small lasers located proximate to one or more fuel combustion zones with alternating wavelengths of light.

Abstract: Improved lockout control in oil primary controllers for oil heating systems which allows a reasonable number of user resets and ignition retries in the event of lockout, while minimizing the unwanted accumulation of oil in the combustion chamber of the heating system. When the oil primary goes into lockout mode due to failure of combustion to take place, the oil primary is placed in a restricted mode of operation in which a limited number of reset activations and combustion retries may be attempted. If they are unsuccessful, a waiting time interval is then imposed between further successive attempts. The lockout or trial for ignition time may also be reduced for subsequent attempts, to minimize flooding. Normal operation is returned once a successful combustion cycle has been achieved.

Abstract: In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones. In two embodiments the beam from the excitation light source is split with a portion of it going to the ignitor laser and a second portion of it being combined with either the first portion after a delay before injection into the ignitor laser or combined with the output of the ignitor laser. In another embodiment alternating short and long pulses of light from the excitation light source are directed into the ignitor laser.

Abstract: In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones. In the embodiment of the invention claimed herein, the beam from the excitation light source is split with a portion of it going to the ignitor laser and a second portion of it being combined with either the first portion after a delay before injection into the ignitor laser.

Abstract: A method for controlling the combustion of burners in a batch-type combustion furnace, includes the steps of electrically linking a where the fuel gas control valves are electrically linking to corresponding air control valves for each of the burners in a batch-type combustion furnace. The method includes the steps of preliminarily calibrating the air-fuel ratio adjusted with zero and span adjustments between the fuel gas control valve and the corresponding air control valve so as to give a theoretical air-fuel ratio when same electric signals are given to the fuel gas control valve and the air control valve.

Abstract: The invention concerns a pre-vaporizing and pre-mixing burner for liquid fuels which has a fuel feed line (56), a pump which pressurizes the fuel in the feed line, a mixing region (123) and a fuel valve (119) which opens out into the mixing region and by means of which the fuel is atomized and fed to the air for combustion (127). According to the invention, the fuel is vaporized in an optimum manner in that the fuel valve opens automatically as from a given fuel pressure, and a heating device (128) is associated with the fuel valve.

Abstract: A method for a security control of a burner, provided with a body (1) comprising a diffuser (2; 8) in which apertures (3) for the flow of a mixture of air and fuel are made, comprises detecting a temperature representative of the temperature of said diffuser in at least one zone of the diffuser, generating a signal having an intensity depending on said representative temperature.

Abstract: A method and apparatus is provided for initiating and stabilizing fuel combustion in applications such as gas turbine electrical power generating engines and jet turbine engines where it is desired to burn lean fuel/air mixtures which produce lower amounts of NOx. A laser induced spark is propagated at a distance from the fuel nozzle with the laser ignitor being remotely located from the high temperature environment of the combustion chamber. A laser initiating spark generated by focusing high peak power laser light to a sufficiently tight laser spot within the fuel to cause the ionization of air and fuel into a plasma is unobtrusive to the flow dynamics of the combustion chamber of a fuel injector, thereby facilitating whatever advantage can be taken of flow dynamics in the design of the fuel injector.

Abstract: A combustor method and apparatus is provided. The method utilizes flameless combustion with one or more of three improvements to enhance ignition of the flameless combustor. A catalytic surface can be provided within a combustion chamber to provide flameless combustion at least in the vicinity of the catalytic surface at a temperature that is much lower than the autoignition temperature of fuel in air without the presence of the catalytic surface. Nitrous oxide or supplemental oxygen may also be used as an oxidant either instead of air or with air to reduce ignition temperatures. Further, electrical energy can be passed through the fuel conduit, raising the temperature of the conduit to a temperature above which the fuel will ignite when combined with the oxidant.

Abstract: A combustion control method for use in a catalytic combustion system having (a) a gaseous mixture inlet port, located at the upstream side of said catalytic combustion system, for the entrance of a fuel-air mixture; (b) an exhaust gas outlet port, located at the downstream side of said catalytic combustion system, for the exit of an exhaust gas; (c) a primary combustion chamber in which a catalyst body is disposed, said catalyst body being formed of a porous base material with numerous communicating holes that supports thereon an oxidation catalyst; (d) a secondary supply port, located downstream of said primary combustion chamber, for the supply of a gaseous mixture or air; and (e) a secondary combustion chamber located downstream of said secondary supply port; comprising such process that an excess air ratio of said primary combustion chamber is initially set above 1 and after the rate of combustion of said secondary combustion chamber exceeds a given level, combustion is made to take place, with the

Abstract: A soldering iron (1) comprises a soldering head (4) connected to a handle (2). A cylindrical catalytic element (20) located in a combustion chamber (8) converts gas to heat for heating a soldering tip (15). An electrode (40) located within the catalytic element (20) initially ignites a fuel gas/air mixture to burn in a flame (42) within the catalytic element (20) for raising the temperature of a downstream portion (50) of the catalytic element (20) to its ignition temperature. Heat from the downstream portion (50) raises an upstream portion (51) of the catalytic element (20) upstream of the flame (42) to its ignition temperature, which then commences to convert the fuel gas/air mixture to heat. This starves the flame (42) of fuel gas/air mixture, thus extinguishing the flame (42) so that the catalytic element (20) continues to convert fuel gas/air mixture to heat in a catalytic reaction.

Abstract: An ignition system for a gas appliance comprises an ignition controller that receives a current from a power source. The ignition controller is also coupled to an ignitor and to a current actuated valve that releases a flow of gas when the current is greater than a first predetermined current value and less than a second predetermined current value. Ignition safety for the gas appliance is provided by establishing a fixed range of current through the ignitor before the gas valve is opened.

Abstract: A gas oven comprises at least a first burner element disposed within an oven cavity of the gas oven. A first control valve is disposed within a gas line connected to the burner element and to a gas source. The control valve controls gas flow to the burner element. A first temperature sensor is positioned so as to detect temperature about the burner element. A controller is electrically coupled to the temperature sensor and to the control valve wherein the controller ensures successful ignition of the burner element by monitoring the temperature signals generated from the temperature sensor to determine if the temperature signals increase a rate that is greater than a predetermined.

Abstract: An ignition system for a gas appliance comprises an ignitor for igniting gas, a gas valve which controls the flow of gas to the ignitor, and a delay switch which delays the opening of the gas valve. The delay switch comprises a piston and a cylinder which define a chamber. The piston moves between a first position and a second position in the cylinder. The piston is coupled to the gas valve such that when the piston reaches the second position, the gas valve is opened. The chamber includes a large aperture and a small aperture which influence the rate at which the piston moves. The large aperture includes a sealing member which seals the large aperture when the piston moves from the first position to the second position to resist the motion of the piston. The large aperture is opened when the piston moves in the other direction. The delay switch is connected to the ignitor such that when the ignitor is turned on, the piston moves against air resistance and delays the opening of the gas valve.

Abstract: An oxy-burner having a back-up firing system includes an oxidant conduit coupled to an oxidant injector nozzle. A primary oxygen line is coupled to the oxidant conduit and transports oxygen into the oxidant conduit. An auxiliary air ejector is coupled to the oxidant conduit and is configured to receive a motive fluid and to entrain ambient air and force the entrained air into the oxidant conduit. In operation, upon detecting a disruption in the primary oxygen supply, a motive fluid is supplied to the auxiliary air ejector. The motive fluid injected by the auxiliary air ejector entrains ambient air sufficient to either continue operation of the oxy-burner, or provide cooling air to the oxy-burner in the event that the burner is shut down. Upon restoring the primary oxygen supply, the back-up oxy-burner system can be deactivated and the oxy-burner return to standard operation.

Abstract: A catalytic combustion heating device 3 for generating heat by oxidation reaction of fuel gas stored in a fuel tank 24 and air in a combustion unit 29 is installed in a mount 4 provided in a jacket 1. The mount 4 is fastened to the waist of the body wearing the jacket 1 by a holding band 9, and the load applied on the shoulders through the jacket is lessened and comfort is improved. Thus, a warming jacket capable of warming the body comfortably is obtained.

Abstract: An apparatus and method for operating a pilot burner apparatus and a main burner apparatus of a gas-fired appliance. The pilot burner apparatus draws combustion air from a first environment. The main combustion apparatus draws air from a second environment. In a shutdown condition, such as when a flammable vapor source is accidentally exposed to the second environment, the pilot burner apparatus draws air containing an undesired flammable vapor which eliminates the pilot flame, triggering a gas valve to close and shut down the fuel gas supply to the main burner apparatus and the pilot burner apparatus.

Abstract: The invention is directed to a method of operating a burner. The method includes feeding an auxiliary gas into a liquid fuel upstream of an injection orifice during the ignition and during part load of the burner, and interrupting the feeding of the auxiliary gases within high load ranges of the burner.

Abstract: A dual mode pilot burner having a control flame mode of operation and a pilot flame mode of operation, which dual mode pilot burner is suitable for controlling the fuel/air ratio of a main burner when operating in the control flame mode of operation. The dual mode pilot burner includes a burner body having a control flame holder and a pilot flame holder disposed downstream of the control flame holder, a mixing chamber having a fuel gas inlet, an oxidant inlet, and a mixed gas outlet, which mixed gas outlet is in fluid communication with the control flame holder and a fuel gas control valve for controlling a fuel gas flow rate through the fuel gas inlet into the mixing chamber.

Abstract: A direct ignition type pulsated combustion apparatus including a burner provided in a combustion furnace, a combustion air line connected to the burner for feeding combustion air to the burner, a fuel gas line connected to the burner for feeding a fuel gas to the burner, an air valve and a fuel valve provided in the combustion air line and the fuel gas line, respectively. A plurality of actuators provided for the air valve and the fuel valve are adapted to open and close the air valve and the fuel valve, respectively. An air bypass line is provided in the combustion air line to bypass the air valve. A fuel bypass line provided in the fuel gas line for bypassing the fuel gas valve. A control unit actuates the opening/closing cycles and timings of the air and the fuel gas valves connected to the actuators, respectively, allowing the cycle time of opening and closing the air valve to be controlled independently of the cycle time of opening and closing the fuel gas valve.

Abstract: Methods and compositions for selectively detecting analytes in a homogeneous assay, a heterogeneous assay, or a mixture of the two by contacting a labeled probe:analyte complex with one or more amphiphiles. The invention is also useful for increasing the signal to noise ratio when used in conjunction with other assay systems. In preferred embodiments, the analyte and probe are nucleic acids or proteins.

Abstract: A catalytic combustion type heater set so as to reduce the exhaust emission at the time of ignition and the time of extinguishment by, at the time of ignition, providing a precombustion period and making the amounts of the fuel and air fed larger than the air-fuel ratio of the steady combustion period to prevent incomplete combustion and by, at the time of extinguishment, stopping the feeding of fuel and feeding only air in an amount lower than that before the fuel stops being fed so as to completely burn the remaining fuel, then feeding purging air.

Abstract: A modulated burner combustion system that prevents the use of components that were originally not commissioned for use in the system. The present invention uses actuators that contain unique stored identification numbers. When the system is initially configured or commissioned, the unique identification numbers of the actuators are stored in nonvolatile memory in a fuel/air controller. When the system is brought on line, the fuel/air controller microprocessor initially sends false IDs to the actuator together with test control signals to determine if the actuator operates in response to the false identification numbers. If the actuator does operate in response to the false identification numbers, that is an indication that the system has been tampered with and the system is, consequently, shut down. Subsequently, the true identification numbers are transmitted to the actuators with test control signals.

Abstract: A gas oven comprises at least a first burner element disposed within an oven cavity of the gas oven. A first control valve is disposed within a gas line connected to the burner element and to a gas source. The control valve controls gas flow to the burner element. A first temperature sensor is positioned so as to detect temperature about the burner element. A controller is electrically coupled to the temperature sensor and to the control valve wherein the controller ensures successful ignition of the burner element by monitoring the temperature signals generated from the temperature sensor to determine if the temperature signals increase a rate that is greater than a predetermined.

Abstract: A gas burner system including a burner body having a flange providing an annular surface. A removable cap is disposed above the burner body and contacts the annular surface for forming an annular interface with the burner body for closing the burner body. A plurality of ports are provided along the annular interface between the burner body and the cap. A first ignitor is disposed adjacent the annular interface between the burner body and cap. A second ignitor is also disposed adjacent the annular interface between the burned body and cap. Electronic means energize the first and second ignitors for generating sparks to ignite the gas burner. The energizing means include means for sensing the presence of flame at both the first and second ignitors such that during burner operation, if no flame is sensed at both the first and second ignitors, the ignitors are energized for generating sparks.

Abstract: An atmospheric burner is associated with a flame presence sensor and an electrical-discharge ignition device. It is fed via a flow rate control device. Both the ignition device and the flow rate control device are controlled by a microcontroller. A user interface enables the user to select the desired power by sending to the microcontroller a request for altering the flow rate and hence for altering the minimum power deliverable by the burner.

Abstract: A method for controlling an igniting operation for a gas boiler for preventing an explosive ignition is disclosed. The gas boiler is equipped with a burner for burning a gas, a fan for exhausting a burnt gas in the burner, and an ignition plug for performing igniting operation of the gas supplied into the burner. If the operation of the gas boiler commences, the gas is supplied into the burner while the exhaust fan is operated at a low speed appropriate for performing the igniting operation, and the ignition plug is operated to perform the igniting operation of the gas in the burner. In that situation, if ignition does not occur during a predetermined time, the rotational velocity of the exhaust fan increases, whereby the density of gas in the burner is maintained constant. Thus, the excessive increasing of the gas density is prevented, so the explosive ignition is prevented.

Abstract: In one aspect of the present invention, an automatic screed temperature control is disclosed. The control senses the screed temperature and compares the screed temperature to a lower set point. In response to the screed temperature being less than the lower set point, the control causes fuel to dispense into the combustion chamber and subsequently causes the fuel to ignite in order to heat the screed. The screed is heated until the screed temperature becomes greater than an upper set point.

Abstract: A burner for a vehicle heater of a particle filter regenerator including a combustion air blower, a combustion chamber with a fuel evaporator, a fuel supply with a fuel metering pump by which the fuel is proportionately fed to the evaporator, a glow-plug to ignite a mixture of combustion air and vaporized fuel and a control device, in which the control device switches the flow-plug on to ignite the mixture, starts the fuel metering pump after a first period following the switch-on of the glow-plug and substantially simultaneously with the starting of the fuel metering pump or a second period thereafter initiates a gradual increase in the speed of the combustion gas blower from a standstill or low speed rotation.

Abstract: A gas oven having an electronic controller for directly controlling the gas valve and burner ignition. The controller opens the gas valve and activates the ignitor whenever oven heating is required and then determines whether ignition has occurred, detected by an indicator of ignition, often a conventional oven thermostat, a thermocouple, a resistance temperature device (RTD), or other type of temperature sensor. Positive proof of ignition is given by determining whether the detected temperature is increasing at a particular rate. The gas valve is closed if ignition does not occur within a predetermined time, preferably about 10-15 seconds. Re-ignition may be attempted after a sufficient delay. The controller also closes the gas valve whenever the oven temperature is decreasing at a predetermined rate or is increasing at less than a predetermined rate.

Abstract: There is provided a method of fuel/oxidizer ignition comprising: (a) application of laser light to a material surface which is absorptive to the laser radiation; (b) heating of the material surface with the laser light to produce a high temperature ablation plume which emanates from the heated surface as an intensely hot cloud of vaporized surface material; and (c) contacting the fuel/oxidizer mixture with the hot ablation cloud at or near the surface of the material in order to heat the fuel to a temperature sufficient to initiate fuel ignition.

Abstract: A detection system includes flame sources at least two of which are independently controllable; photodetectors each having an independent view of the flame sources and being capable of producing a respective current signal in response to flames produced by the flame sources; and a device for analyzing the current signals to determine state values of a plurality of state variables and transform the state values into at least one parameter value. A number of the flame sources is at least as high as a number of the state variables, and a number of the photodetectors is at least as high as the number of the state variables. In one embodiment, the flame sources include gas burners in a gas combustion chamber, the photodetectors include silicon carbide photodiodes, and the parameter value is representative of fuel rate, temperature, acoustic dynamics, nitrogen oxide concentration, or carbon monoxide concentration.

Abstract: A method for gas supply pressure control is disclosed. Gas is supplied to a gas burner at a gas supply pressure which is higher than an ignition pressure, and after the ignition of the gas burner, the gas supply pressure increases during a predetermined time until fluid to be heated reaches a target temperature. The increase of the gas supply pressure is performed gradually according to a predetermined number of pressure levels set between the ignition pressure and maximum gas supply pressure of the gas boiler. If the fluid reaches the target temperature, the gas is supplied according to a corresponding to the target pressure temperature. Since the time that the gas is supplied at the maximum gas supply pressure is reduced during the time of initial operation of the gas boiler and during the operation of the gas boiler, the noise resulting from combustion is reduced.

Abstract: A flame sensor senses the intensity of a pilot flame to determine whether main burner ignition has occurred in a gas furnace. The sensor includes a computer which is operative to trigger the sensing of the flame intensity following the provision of gas to the main burner. Circuitry associated with the computer preferably provides an indication of the pilot flame intensity to the computer through a measurement of the electrical conductivity of the pilot flame following provision of gas to the main burner.

Abstract: A method and apparatus for relighting a gas oven following interruption in the operation thereof due to a temporary failure or reduction in the energy level of a source of electric energy comprises instantaneously disconnecting the delivery of pressurized gas to the oven in response to a reduction in the level of the electric energy, slowly reducing the pressure of gas in the delivery system, monitoring the pressure of the gas, and restoring the delivery of fuel to the oven only if the energy supply is restored to a proper level within a short period of time and prior to a predetermined reduction of the gas pressure.

Abstract: This invention relates to a method and system for controlling a heating/air conditioning unit. More particularly, this invention relates to a control unit which detects the presence of one or more gases (e.g. CO, fuel, refrigerant or radon) produced by the heating/air conditioning unit and disables the heating/air conditioning unit if gases are present in undesired concentrations. In one embodiment of the present invention, the presence of multiple gases are detected and a separate indication for each gas is provided. An alternate embodiment of the present invention provides means for resetting the heating/air conditioning unit a selected number of times after the heating/air conditioning unit has been disabled due to the presence of a gas in undesired levels. An alternative embodiment of the present invention provides means for disabling the central heating/air conditioning unit based upon the activation of one or more smoke alarms.

Abstract: A fuel control system, a control device therefor and methods of making and operating the same are provided, the fuel control system comprising a source of fuel a burner unit, an electrically operated valve unit adapted to be opened to interconnect the source of fuel to the burner unit when the valve unit is energized, the valve unit having a coil, an electrical power source having a value sufficient for opening the valve unit when operatively interconnected to the coil to energize the coil, a control device for operatively interconnecting the power source to the coil when the control device determines that fuel should be directed to the burner unit, the control device being so constructed and arranged that the control device is adapted to operatively interconnect the power source to the coil without the use of relay contacts between the power source and the coil.

Abstract: Method for igniting an air/fuel spray (26) comprised of fuel droplets including a coherent optical source (12) for introducing at least one pulse of coherent radiation into the air/fuel spray. The pulse generates free electrons and initiates a development of a plasma within the air/fuel spray. The coherent source maintains the pulse of coherent radiation and pumps the developing plasma to higher energies. The pulse is terminated at a time after the plasma has reached a predetermined energy and before ignition of the air/fuel spray. The non-linear ignition system of the invention employs a gas/vapor interface region at a fuel droplet surface and an electric field that extends from and exists outside of a fuel droplet. Free electrons are accelerated to higher energies by the electric field surrounding the fuel droplet. The accelerated electrons initiate a breakdown near adjacent fuel droplets and the liberation of further free electrons.

Abstract: A flame rectification type flame sensor circuit and method in which a generator injects periodic pulses of alternating voltage into a flame region, the voltage across the flame region being processed by a filter/amplifier which, in proper operation, produces a non-zero output signal only during the time a flame is present and a pulse of alternating voltage is being supplied by the generator. Final indication of a flame is produced only if a non-zero output signal occurs during the time a pulse of alternating voltage is being supplied, and not during the time between successive pulses of alternating voltage. Failure of an electrical component in the filter/amplifier is indicated if a non-zero output signal occurs during the time between successive pulses of alternating voltage.

Abstract: A dimmer device for a gas light which is solar activated and is composed of a minimum number of parts. A magnetically operated valve with a magnetically attractable ball is energized during daylight hours to close off one passageway yet allows gas to flow through a second passageway at a lower flow rate to provide a dimmer condition for the lamp. At night time, the magnetic valve is deactivated causing the magnetically attractable ball to open the otherwise closed passageway and thereby allow full gas flow to the lamp. The dimmer device is easily installed into the lamp housing rather than the post.

Abstract: A pilot for a gas fuel burner assembly is controlled so that the pilot is extinguished when the burner is ignited and lit when the burner is extinguished.

Abstract: An electrically operated line valve has its outlet connected to the inlet of the manifold for supplying the user actuated individual gas burner valves and a user actuated line power switch is closed before opening of any of the burner valves. A valve position detector signals an electronic controller which supplies power to the line switch only if a burner valve has been opened after closing of the line switch. A user actuatable manual override cable enables the line valve to be manually opened during periods of electrical power outage.

Abstract: A gas and solid fuel burning chamber is provided with a control system for the safe and efficient operation of a gas burner. The simple control system uses multiple thermocouples in series to permit the safe operation of the gas burner in a vented device without the need for a draft hood. A combination of gas and solid fuel is demonstrated where gas can be used to start the solid or as an independent source of heat. The control system comprises generally of thermocouples for measuring the flame temperature, the combusted gas temperature and the overall chamber internal temperature and producing signals to regulate the flow of fuel to the gas burner in response thereto.

Abstract: An electric control system for a pulse combustion device of the type which includes a combustion chamber mounted within a liquid vessel of a liquid heating apparatus, fuel and air inlet valves arranged to supply a mixture of fuel and air into the combustion chamber, a tailpipe connected at one end thereof to an exhaust port of the combustion chamber to take place therein resonant combustion of the mixture of fuel and air and immersed in an amount of liquid stored in the vessel, and an electrically operated air intake blower arranged to supply fresh air into the combustion chamber through the air inlet valve.

Abstract: According to this invention there is provided a process and apparatus for the ignition of a pilot burner in an inert atmosphere without substantially contaminating the inert atmosphere. The process includes the steps of providing a controlled amount of combustion air for a predetermined interval of time to the combustor then substantially simultaneously providing a controlled mixture of fuel and air to the pilot burner and to a flame generator. The controlled mixture of fuel and air to the flame generator is then periodically energized to produce a secondary flame. With the secondary flame the controlled mixture of fuel and air to the pilot burner and the combustion air is ignited to produce a pilot burner flame. The pilot burner flame is then used to ignited a mixture of main fuel and combustion air to produce a main burner flame.

Abstract: A fuel control system, a control unit therefor and methods of making the same are provided, the system comprising a control unit that reduces the length of the warm-up time period of an igniter in subsequent successive burner cycles in which ignition is successful until the control device detects an increase in the length of the flame detecting time period in that particular successive burner cycle over the length of the flame detecting time period on a previous burner cycle at which time the control device then increases the length of the previously reduced warm-up time period a certain amount.

Abstract: A burner control system with an interrupted or intermittent type of pilot burner has a special feature allowing transitions between a pilot flame hold state where the pilot flame only burns and the run state where the main burner is operating. Each transition to the pilot flame hold state from the run state comprises a brief period in which presence of the pilot flame is assured while the main flame is extinguished. Transitions to the run state from the pilot flame hold state may proceed directly through the main flame establishment period to the run state, thereby eliminating the time-consuming purging and pilot flame ignition phases.

Abstract: A heat exchanger system, a fuel control system therefor and methods of making the same are provided, the fuel control system having an electrical circuit means that comprises an ignition trial portion, a flame sensing control portion and a timer portion that comprises a counter having a plurality of outputs and a timer that clocks the output of the counter on each discharge of the timer, the timer portion also comprising a capacitor, a trial time resistor and a wait time resistor that are selectively placed in series with the capacitor by the counter when clocked to certain outputs by the timer to determine an ignition trial time period and a wait time period, and a transistor operatively interconnected to the capacitor to discharge the capacitor when flame is sensed by the flame sense portion.