Convection heater

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A convection heater for single-room use. Electric Heater.jpg
A convection heater for single-room use.
Illustration of the Model "S" Convection Heater by Sala Heater & Mantel, 1924 Model "S" Convection Heater - 1924.png
Illustration of the Model "S" Convection Heater by Sala Heater & Mantel, 1924

A convection heater (otherwise known as a convector heater) is a type of heater that uses convection currents to heat and circulate air. These air currents flow throughout the body of the appliance and across its heating element. This process takes advantage of thermal conduction in order to heat the air, reducing its density relative to colder air and causing it to rise. [1]

Contents

As heated air molecules rise, they displace cooler air molecules down towards the heating appliance. The displaced cool air is heated as a result, decreases in density, rises, and repeats the cycle.

History

Ancient heating systems, including hearths, furnaces, and stoves, operated primarily through convection. Fixed central hearths, which were first excavated and retrieved in Greece, date back to 2500 BC, whereas crude fireplaces were used as early as the 800s AD and in the 13th century, when castles in Europe were built with fireplaces with a crude form of chimney. [2]

Developments in convection heating technology included the publication of the very first manual on fireplace design called Mechanique du Feu in 1713, the creation of stoves with thermostatic control in 1849, and the rise of numerous cast iron stove manufacturers during the American Civil War. [2]

The Model "S", illustrated by the Sala Heater & Mantel Co. in Dallas, Texas in 1924, is an example of an early model of a convection space heater. This model consisted of three stoves and was considered to be a highly efficient radiant type of gas heater at the time. It utilized radiant heat, and supplemented its power by drawing cold air through the facing, heating it, and forcing it out through the register. This allowed air circulation while maintaining a cool exterior on the appliance. [3]

These early developments, along with the technological advancements made possible by electricity and inventions of tools like thermostats, gave way for the design of modern convection heaters.

Types

Convection heaters are commonly classified according to their power source. Electric convection heaters use electricity, while combustion or gas-fired heaters use gas, propane, or any other type of fuel. For the heating element, convection heaters usually use metal coils, nickel-chromium, resistance wire, thermal fluids, or ceramic. [4]

Panel heater

A panel heater is a type of electric convection heater commonly used for heating rooms in residential and small commercial settings. They are often mistaken for electric radiators, which are devices that use radiant heating and transfer heat directly to objects rather than using the air as a medium. Panel heaters are typically used in complement to some other primary or central heating system. They are usually fitted with time and temperature controls. [5]

Fan heater

Fan heaters combine the warming capability of a heater and air distribution capacity of a fan. The earliest fan heaters became available in the 1950s, right after the invention of tangential fans. [5] Modern fan heaters have variable-speed fans that can work independently from the heating element. [5]

Institutional convector heater

Institutional convector heaters are heavy-duty heaters designed strictly for commercial and industrial use. [4] Their construction is designed to reach a broad surface area.

Oil heater

An oil heater, also called a column heater, is electrically heated and uses oil as a heat reservoir. Because oil has a high heat capacity and a high boiling point, it is a suitable heat pathway between the heating element and the cavities of the heater unit. [4] [ further explanation needed ]

Gas-fired convection heater

Gas-fired convection heaters use a gas supply instead of electricity. These heaters consist of a gas burner, an air filter, gas valves, a blower, and a thermostat. [5]

See also

Related Research Articles

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<span class="mw-page-title-main">Oven</span> Enclosed chamber for heating objects

An oven is a tool which is used to expose materials to a hot environment. Ovens contain a hollow chamber and provide a means of heating the chamber in a controlled way. In use since antiquity, they have been used to accomplish a wide variety of tasks requiring controlled heating. Because they are used for a variety of purposes, there are many different types of ovens. These types differ depending on their intended purpose and based upon how they generate heat.

<span class="mw-page-title-main">Water heating</span> Thermodynamic process that uses energy sources to heat water

Water heating is a heat transfer process that uses an energy source to heat water above its initial temperature. Typical domestic uses of hot water include cooking, cleaning, bathing, and space heating. In industry, hot water and water heated to steam have many uses.

<span class="mw-page-title-main">Kitchen stove</span> Kitchen appliance designed for the purpose of cooking food

A kitchen stove, often called simply a stove or a cooker, is a kitchen appliance designed for the purpose of cooking food. Kitchen stoves rely on the application of direct heat for the cooking process and may also contain an oven, used for baking. "Cookstoves" are heated by burning wood or charcoal; "gas stoves" are heated by gas; and "electric stoves" by electricity. A stove with a built-in cooktop is also called a range.

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

A central heating system provides warmth to a number of spaces within a building from one main source of heat. It is a component of heating, ventilation, and air conditioning systems, which can both cool and warm interior spaces.

<span class="mw-page-title-main">Storage heater</span>

A storage heater or heat bank (Australia) is an electrical heater which stores thermal energy during the evening, or at night when electricity is available at lower cost, and releases the heat during the day as required. Alternatively, solar storage heaters are designed to store solar energy as heat, to be released during the night or other periods where it is required, often making it more cost effective than selling surplus electricity to the grid and buying it back at night.

<span class="mw-page-title-main">Heating element</span> Device that converts electricity into heat

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<span class="mw-page-title-main">Electric stove</span> Stove with an integrated electrical heating device to cook and bake

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<span class="mw-page-title-main">Gas heater</span>

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.

<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">Fan heater</span> Heat producing machine to increase temperature of an enclosed space

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<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">Underfloor heating</span> Form of central heating and cooling

Underfloor heating and cooling is a form of central heating and cooling that achieves indoor climate control for thermal comfort using hydronic or electrical heating elements embedded in a floor. Heating is achieved by conduction, radiation and convection. Use of underfloor heating dates back to the Neoglacial and Neolithic periods.

<span class="mw-page-title-main">Space heater</span> Household appliance that heats a single room or other small area

A space heater is a device used to heat a single, small- to medium-sized area. This type of heater can be contrasted with central heating, which distributes heat to multiple areas.

<span class="mw-page-title-main">Electric fireplace</span> Electric heater that mimics a fireplace

An electric fireplace is an electric heater that mimics a fireplace burning coal, wood, or natural gas. Electric fireplaces are often placed in conventional fireplaces, which can then no longer be used for conventional fires. They plug into the wall, and can run on a "flame only" setting, or can be used as a heater, typically consuming 1.4 to 1.6 kW to heat a 40 m2 room.

<span class="mw-page-title-main">Oil heater</span> Type of convection heater

An oil heater, also known as an oil-filled heater, oil-filled radiator, or column heater, is a common form of convection heater used in domestic heating. Although filled with oil, it is electrically heated and does not involve burning any oil fuel; the oil is used as a heat reservoir (buffer).

<span class="mw-page-title-main">Fireplace insert</span>

The fireplace insert is a device that can be inserted into an existing masonry or prefabricated wood fireplace.

<span class="mw-page-title-main">Radiator (heating)</span> Heat exchanger for space heating

Radiators and convectors are heat exchangers designed to transfer thermal energy from one medium to another for the purpose of space heating.

<span class="mw-page-title-main">Grate heater</span>

A tubular grate heater is any grate or heat exchanger for a fireplace designed from metal tubing. Through the tubing is circulated home air that becomes heated by the fire. The air is then vented back into the room and home. It is a heat recovery device that improves the efficiency and ability of a fireplace to get the heat from the fire out and into the home. From simple to ornate, they can contribute significantly to the overall comfort of a room and potentially to a whole house. This in turn will reduce the amount of firewood needed to achieve the same comfort level, potentially reducing heating costs and expenses. Heaters increase the efficiency of a fireplace and hence the amount of heat that makes it from the fireplace out into the home. They work by having naturally convected and forced air funneled into the metal heat exchanger tubing that is then heated by the coals and/or fire. They draw in cold air from the floor and blow heated air back out into your home. This adds an element of conductive and convective heating to the radiant heat typical of a basic fireplace. Grate heaters have been called many things: heatilator, hearth heater, fireplace blower, fireplace grate heater, Fireplace Furnace, tubular grate heater, etc.

References

  1. Shah, Y.T. (2018). Thermal energy: Sources, recovery, and applications. 6000 Broken Sound, Parkway NW: Taylor & Francis Group. ISBN   9781315305936.{{cite book}}: CS1 maint: location (link)
  2. 1 2 Nagengast (2001). "An early history of comfort heating". The ACHR News. Retrieved 11 November 2019.
  3. Sala, Theodore. "The Sala Model S". Sala Heater Catalog 1924. Sala Heater and Mantel Co. Retrieved 1 September 2012.
  4. 1 2 3 dela Cruz, R. (n.d.). "Convection heaters: Everything you need to know". Engineer Warehouse Learning Center. Retrieved 13 November 2019.
  5. 1 2 3 4 Smith, C. (2007). This cold house: The simple science of energy efficiency. Baltimore: The Johns Hopkins University Press.