Gas heater

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Upright non-flued liquefied petroleum gas heater, 1970s Gas heater 1970s.jpg
Upright non-flued liquefied petroleum gas heater, 1970s
A wall mounted gas heater that runs on either propane or natural gas. Wall heater.jpg
A wall mounted gas heater that runs on either propane or natural gas.

A gas heater is a space heater used to heat a room or outdoor area by burning natural gas, liquefied petroleum gas, propane, or butane.

Contents

Indoor household gas heaters can be broadly categorized in one of two ways: flued or non-flued, or vented and unvented.

History

The first gas heater made use of the same principles as the Bunsen burner. Beginning in 1881, the burner's flame was used to heat a structure made of asbestos, a design patented by Sigismund Leoni, a British engineer. Later, fire clay replaced the asbestos because it is easier to mold. Modern gas heaters still work this way, although they now use other refractory materials.

Function

The gas heater is able to warm up a whole room by first allowing the flame to heat the air locally, then it disperses throughout the air by convection. Today the same principle applies with outdoor patio heaters or "mushroom heaters" which act as giant Bunsen burners.

Modern gas heaters have been further developed to include units that utilize radiant heat technology, rather than the principles of the Bunsen burner. This form of technology does not spread via convection, but rather, is absorbed by people and objects in its path. This form of heating is useful for outdoor heating, where it is more economical than using a standard air heating system.

Flued heaters

A flued heater that burns wood for heat. Any byproducts leave through the flue pipe in the back Good woodburning stove.jpg
A flued heater that burns wood for heat. Any byproducts leave through the flue pipe in the back

Flued heaters are permanently installed wherever they are placed. The flue, if properly installed with the correct overall height, size, and orientation should extract all of the heater emissions. A correctly operating flued gas heater is typically safe for use.

Non-flued heaters

Another example of a non-flued gas heater, running on natural gas. Gas Heater of 2000s.jpg
Another example of a non-flued gas heater, running on natural gas.

Non-flued heaters – also known as unvented heaters, vent-free heaters, or flueless fires, may be either permanently installed or portable, and sometimes incorporate a catalytic converter. [1] Non-flued heaters can be risky if appropriate safety procedures are not followed. There must be adequate ventilation, they must be kept clean, and they should always be switched off before sleeping. If operating correctly, the main emissions of a non-flued gas heater are water vapour, carbon dioxide, and nitrogen dioxide.

Operation

Home gas heating controls cycle using a mechanical or electronic thermostat. Gas flow is actuated with a valve. Ignition is by an electric filament or pilot light. Flames heat a radiator in the air duct but outside the flue, convection or a fan may distribute the heat.

See also

Related Research Articles

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<span class="mw-page-title-main">Furnace (central heating)</span> Device used for heating buildings

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<span class="mw-page-title-main">Chimney</span> Ventilation for hot gases or smoke

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<span class="mw-page-title-main">Central heating</span> Type of heating system

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<span class="mw-page-title-main">Fireplace</span> Device for firing solid fuels in buildings

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<span class="mw-page-title-main">Gas stove</span> Type of cooking stove

A gas stove is a stove that is fuelled by combustible gas such as syngas, natural gas, propane, butane, liquefied petroleum gas 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.

<span class="mw-page-title-main">Pilot light</span> Small gas flame used to light larger gas burner

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.

<span class="mw-page-title-main">Flue</span> Exhaust for a fireplace, furnace etc

A flue is a duct, pipe, or opening in a chimney for conveying exhaust gases from a fireplace, furnace, water heater, boiler, or generator to the outdoors. Historically the term flue meant the chimney itself. In the United States, they are also known as vents for boilers and as breeching for water heaters and modern furnaces. They usually operate by buoyancy, also known as the stack effect, or the combustion products may be 'induced' via a blower. As combustion products contain carbon monoxide and other dangerous compounds, proper 'draft', and admission of replacement air is imperative. Building codes, and other standards, regulate their materials, design, and installation.

<span class="mw-page-title-main">Pellet stove</span> Stove that uses pellet fuel

A pellet stove is a stove that burns compressed wood or biomass pellets to create a source of heat for residential and sometimes industrial spaces. By steadily feeding fuel from a storage container (hopper) into a burn pot area, it produces a constant flame that requires little to no physical adjustments. Today's central heating systems operated with wood pellets as a renewable energy source can reach an efficiency factor of more than 90%.

<span class="mw-page-title-main">Electric heating</span> Process in which electrical energy is converted to heat

Electric heating is a process in which electrical energy is converted directly to heat energy. Common applications include space heating, cooking, water heating and industrial processes. An electric heater is an electrical device that converts an electric current into heat. The heating element inside every electric heater is an electrical resistor, and works on the principle of Joule heating: an electric current passing through a resistor will convert that electrical energy into heat energy. Most modern electric heating devices use nichrome wire as the active element; the heating element, depicted on the right, uses nichrome wire supported by ceramic insulators.

<span class="mw-page-title-main">Masonry heater</span> Heating device

A masonry heater is a device for warming an interior space through radiant heating, by capturing the heat from periodic burning of fuel, and then radiating the heat at a fairly constant temperature for a long period. Masonry heaters covered in tile are called cocklestoves. The technology has existed in different forms, from back into the Neoglacial and Neolithic periods. Archaeological digs have revealed excavations of ancient inhabitants utilizing hot smoke from fires in their subterranean dwellings, to radiate into the living spaces. These early forms have evolved into modern systems.

<span class="mw-page-title-main">Kerosene heater</span> Typically a portable, unvented, kerosene-fueled, space heating device

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.

Condensing boilers are water heaters typically used for heating systems that are fueled by gas or oil. When operated in the correct circumstances, a heating system can achieve high efficiency by condensing water vapour found in the exhaust gases in a heat exchanger to preheat the circulating water. This recovers the latent heat of vaporisation, which would otherwise have been wasted. The condensate is sent to a drain. In many countries, the use of condensing boilers is compulsory or encouraged with financial incentives.

<span class="mw-page-title-main">LO-NOx burner</span>

A LO NOx burner is a type of burner that is typically used in utility boilers to produce steam and electricity.

<span class="mw-page-title-main">Wood-burning stove</span> Type of stove

A wood-burning stove is a heating or cooking appliance capable of burning wood fuel, often called solid fuel, and wood-derived biomass fuel, such as sawdust bricks. Generally the appliance consists of a solid metal closed firebox, often lined by fire brick, and one or more air controls. The first wood-burning stove was patented in Strasbourg in 1557. This was two centuries before the Industrial Revolution, so iron was still prohibitively expensive. The first wood-burning stoves were high-end consumer items and only gradually became used widely.

A catalytic heater is a flameless heater which relies on catalyzed chemical reactions to break down molecules and produce califaction (heat). When the catalyst, fuel, and oxygen combine together, they react at a low enough temperature that a flame is not produced. This process keeps repeating itself until either oxygen or the fuel source is taken out of the equation.

A direct vent fireplace is a prefabricated metal fireplace that employs a direct-vent combustion system. "Direct vent" refers to a sealed-combustion system in which air for combustion is drawn from the outdoors, and waste combustion gasses are exhausted to the outdoors. "Direct vent" does not simply mean that all gasses from combustion are vented to the exterior of the structure in which it is installed.

<span class="mw-page-title-main">Industrial furnace</span> Device used for providing heat in industrial applications

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.

References

  1. "RR023 - Flueless gas fires - concentration of carbon monoxid..." www.hse.gov.uk.