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Auto reignition is a process used in gas burners to control ignition devices based on whether a burner flame is lit. This information can be used to stop an ignition device from sparking, which is no longer necessary after the flame is lit. It can also be used to start the sparking device again if the flame goes out while the burner is still supplying gas, for example, from a gust of wind or vibration.
Most gas ranges and cooktops use sparking devices to ignite the burner flame. This eliminates the need for a pilot flame, which wastes energy. Most of these sparking device-equipped ranges require the user to control the ignition sparking manually, resulting in a three-step process required to operate the burner:
One implementation of a gas burner with auto reignition senses the electrical conductivity of the flame. This nonzero flame conductivity is because combustion of natural gas releases enough free electrons to support a small current in air. An electronic circuit then starts or stops the igniter from sparking, based on whether the flame is lit. This reduces the number of steps to turn a burner on from three to one:
This is an elegant solution, compared to detecting flame via a thermocouple, a photoresistor or a mercury-filled sensor. No extra components or electrical connections between the sparker electrode and the spark module electronics are required.
This convenience and safety feature is found only (as of June 2009) on higher priced gas ranges and cooktops.
Auto reignition lowers the risk of gas leaks:
This feature is especially valuable on gas burners with several different short-term users, less likely to bother with or learn multi-step procedures—for example, gas ranges in rental properties, guest houses, or in office kitchens.
A thermocouple, also known as a "thermoelectrical thermometer", is an electrical device consisting of two dissimilar electrical conductors forming an electrical junction. A thermocouple produces a temperature-dependent voltage as a result of the Seebeck effect, and this voltage can be interpreted to measure temperature. Thermocouples are widely used as temperature sensors.
A spark plug is an electrical device used in an internal combustion engine to produce a spark which ignites the air-fuel mixture in the combustion chamber. As part of the engine's ignition system, the spark plug receives high-voltage electricity which it uses to generate a spark in the small gap between the positive and negative electrodes. The timing of the spark is a key factor in the engine's behaviour, and the spark plug usually operates shortly before the combustion stroke commences.
A hot-tube ignitor was an early device that fit onto the cylinder head of an internal-combustion engine, used to ignite the compressed fuel/air mixture by means of a flame heating part of the tube red-hot. A hot-tube ignitor consisted of a metal or porcelain tube, closed at one end and attached to the cylinder head at the other and an adjustable burner that could be moved to position its flame at any point along the length of the tube.
A spark gap consists of an arrangement of two conducting electrodes separated by a gap usually filled with a gas such as air, designed to allow an electric spark to pass between the conductors. When the potential difference between the conductors exceeds the breakdown voltage of the gas within the gap, a spark forms, ionizing the gas and drastically reducing its electrical resistance. An electric current then flows until the path of ionized gas is broken or the current reduces below a minimum value called the "holding current". This usually happens when the voltage drops, but in some cases occurs when the heated gas rises, stretching out and then breaking the filament of ionized gas. Usually, the action of ionizing the gas is violent and disruptive, often leading to sound, light, and heat.
The autoignition temperature or self-ignition temperature, often called spontaneous ignition temperature or minimum ignition temperature and formerly also known as kindling point, of a substance is the lowest temperature in which it spontaneously ignites in a normal atmosphere without an external source of ignition, such as a flame or spark. This temperature is required to supply the activation energy needed for combustion. The temperature at which a chemical ignites decreases as the pressure is increased.
A lighter is a portable device which creates a controlled flame, and can be used to ignite a variety of flammable items, such as cigarettes, butane gas, fireworks, candles or campfires. A lighter typically consists of a metal or plastic container filled with a flammable liquid, a compressed flammable gas and in rarer cases a flammable solid i.e. rope in a trench lighter, a means of ignition to produce the flame, and some provision for extinguishing the flame or merely controlling it to such a degree that the user may extinguish it with their breath. Alternatively, a lighter can be one which uses electricity to create an electric arc utilizing the created plasma as the source of ignition or a heating element can be used in a similar vein to heat the target to its ignition temperatures, as first formally utilized by Friedrich Wilhelm Schindler to light cigars and now more commonly seen incorporated into the automobile auxiliary power outlet to ignite the target material. Different lighter fuels have different characteristics which is the main influence behind the creation and purchasing of a variety of lighter types.
A flashover is the near-simultaneous ignition of most of the directly exposed combustible material in an enclosed area. When certain organic materials are heated, they undergo thermal decomposition and release flammable gases. Flashover occurs when the majority of the exposed surfaces in a space are heated to their autoignition temperature and emit flammable gases. Flashover normally occurs at 500 °C (932 °F) or 590 °C (1,100 °F) for ordinary combustibles and an incident heat flux at floor level of 20 kilowatts per square metre (2.5 hp/sq ft).
Induction cooking is performed using direct electrical induction heating of cooking vessels, rather than relying on indirect radiation, convection, or thermal conduction. Induction cooking allows high power and very rapid increases in temperature to be achieved: changes in heat settings are instantaneous.
A gas stove is a stove that is fuelled by combustible gas such as natural gas, propane, butane, liquefied petroleum gas, syngas, or other flammable gas. Before the advent of gas, cooking stoves relied on solid fuels such as coal or wood. The first gas stoves were developed in the 1820s and a gas stove factory was established in England in 1836. This new cooking technology had the advantage of being easily adjustable and could be turned off when not in use. The gas stove, however, did not become a commercial success until the 1880s, by which time supplies of piped gas were available in cities and large towns in Britain. The stoves became widespread on the European Continent and in the United States in the early 20th century.
A pilot light is a small gas flame, usually natural gas or liquefied petroleum gas, which serves as an ignition source for a more powerful gas burner. Originally a pilot light was kept permanently alight, but this wastes gas. Now it is more common to light a burner electrically, but gas pilot lights are still used when a high energy ignition source is necessary, as in when lighting a large burner.
An electric spark is an abrupt electrical discharge that occurs when a sufficiently high electric field creates an ionized, electrically conductive channel through a normally-insulating medium, often air or other gases or gas mixtures. Michael Faraday described this phenomenon as "the beautiful flash of light attending the discharge of common electricity".
A cooktop, stovetop or hob, is a device commonly used for cooking that is commonly found in kitchens and used to apply heat to the base of pans or pots. Cooktops are often found integrated with an oven into a kitchen stove but may also be standalone devices. Cooktops are commonly powered by gas or electricity, though oil or other fuels are sometimes used.
A kerosene heater, also known as a paraffin heater, is typically a portable, unvented, kerosene-fueled, space heating device. In Japan and other countries, they are a primary source of home heat. In the United States and Australia, they are a supplemental heat or a source of emergency heat during a power outage. Most kerosene heaters produce between 3.3 and 6.8 kilowatts.
A gas burner is a device that produces a non-controlled flame by mixing a fuel gas such as acetylene, natural gas, or propane with an oxidizer such as the ambient air or supplied oxygen, and allowing for ignition and combustion.
An oil burner is a heating device which burns #1, #2 and #6 heating oils, diesel fuel or other similar fuels. In the United States, ultra low sulfur #2 diesel is the common fuel used. It is dyed red to show that it is road-tax exempt. In most markets of the United States, heating oil is the same specification of fuel as on-road un-dyed diesel.
A flame arrester, deflagration arrester, or flame trap is a device or form of construction that will allow free passage of a gas or gaseous mixture but will interrupt or prevent the passage of flame. It prevents the transmission of flame through a flammable gas/air mixture by quenching the flame on the high surface area provided by an array of small passages through which the flame must pass. The emerging gases are cooled enough to prevent ignition on the protected side.
Flame lift-off in oil fired pressure jet burners is an unwanted condition in which the flame and burner become separated. This condition is most commonly created by excessive combustion air and often results in the loss of flame as the photoelectric cell fails to register the light of the flame, this in turn results in a safety lockout of the control box.
A gas lighter is a device used to ignite a gas stove burner. It is used for gas stoves which do not have automatic ignition systems. It uses a physical phenomenon which is called the piezo-electric effect to generate an electric spark that ignites the combustible gas from the stove’s burner.
This is an alphabetized glossary of terms pertaining to lighting fires, along with their definitions. Firelighting is the process of starting a fire artificially. Fire was an essential tool in early human cultural development. The ignition of any fire, whether natural or artificial, requires completing the fire triangle, usually by initiating the combustion of a suitably flammable material.
An industrial furnace, also known as a direct heater or a direct fired heater, is a device used to provide heat for an industrial process, typically higher than 400 degrees Celsius. They are used to provide heat for a process or can serve as reactor which provides heats of reaction. Furnace designs vary as to its function, heating duty, type of fuel and method of introducing combustion air. Heat is generated by an industrial furnace by mixing fuel with air or oxygen, or from electrical energy. The residual heat will exit the furnace as flue gas. These are designed as per international codes and standards the most common of which are ISO 13705 / American Petroleum Institute (API) Standard 560. Types of industrial furnaces include batch ovens, metallurgical furnaces, vacuum furnaces, and solar furnaces. Industrial furnaces are used in applications such as chemical reactions, cremation, oil refining, and glasswork.