A Rumford fireplace, sometimes known as a Rumford stove, is a tall, shallow fireplace designed by Sir Benjamin Thompson, Count Rumford, an Anglo-American physicist best known for his investigations of heat. Its shallow, angled sides are designed to reflect heat into the room, and its streamlined throat minimizes turbulence, thereby carrying away smoke with little loss of heated room air.
Rumford appears to have first developed an interest in smoking fireplaces following problems encountered following 1794 renovations of the Palmerston family's house in Hanover Square, Westminster, Rumford being at the time in intimate correspondence with Lady Palmerston. Around the end of 1795 Rumford experimented with various designs, his first practical installation being at the Board of Trade in Whitehall. Rumford later installed such fireplaces not only at the Palmerston house, but throughout those of the aristocracy of England. [1]
His designs made the fireplaces smaller and shallower with widely angled covings so they would radiate better. And he streamlined the throat, or in his words "rounded off the breast" so as to "remove those local hindrances which forcibly prevent the smoke from following its natural tendency to go up the chimney..."
Rumford wrote two papers [2] [3] detailing his improvements on fireplaces in 1796 and 1798. He was well known and widely read in his lifetime and almost immediately in the 1790s his "Rumford fireplace" became state-of-the-art worldwide. Subsequent testing of Rumford's designs has shown that their efficiency would qualify them as clean-burning stoves. [4]
The Rumford fireplace created a sensation in London when he introduced the idea of restricting the chimney opening to increase the updraft. [5] He and his workers changed fireplaces by inserting bricks into the hearth to make the side walls angled, and they added a choke to the chimney to create a circulation of air inside the chimney. In the unmodified chimney, smoke rises up the chimney propelled only by buoyancy—the heated gases from the fireplace being lighter than the surrounding air. This is especially ineffective when the fire is first lit, and the temperature and density of the smoke are closer to the ambient air. Thanks to the discontinuity produced by Rumford's brick "smoke shelf", the flow of smoke gases up the chimney became detached from the outside wall at the lip of the shelf. This set up a counter-circulation of outside air which flowed down the backside of the chimney, while a mixture of outside air and smoke flowed up the opposite side. The circulation inside the chimney, and above the smoke shelf, created a dynamic pressure in which the smoke gases were driven up one side of the chimney and cold air was pulled down the other. The air mixed with the rising smoke and increased the combined flow rising up the flue. It produced a circulating air-smoke flow, driving the smoke up into the chimney rather than lingering and often choking the residents. Many fashionable London houses were modified to his instructions and became smoke-free as well as more efficient. Thompson became a celebrity when news of his success became widespread. In an age when fires were the principal source of heat, this simple alteration in the design of fireplaces was copied widely.
Rumford fireplaces were common from 1796, when Count Rumford first wrote about them, until about 1850. Jefferson had them built at Monticello, [6] and Thoreau listed them among the modern conveniences that everyone took for granted. Existing fireplaces could be rebuilt to the Rumford design ("Rumfordized"). [7] There are still many original Rumford fireplaces.
Rumford also invented a cast iron oven, known as the Rumford roaster. They were often installed together. [8] This inspired the development of the kitchen range, also made in cast iron, which gave yet more control of the fire and also was used directly for cooking purposes.
A hearth is the place in a home where a fire is or was traditionally kept for home heating and for cooking, usually constituted by at least a horizontal hearthstone and often enclosed to varying degrees by any combination of reredos, fireplace, oven, smoke hood, or chimney. Hearths are usually composed of masonry such as brick or stone. For millennia, the hearth was such an integral part of a home, usually its central and most important feature, that the concept has been generalized to refer to a homeplace or household, as in the terms "hearth and home" and "keep the home fires burning". In the modern era, since the advent of central heating, hearths are usually less central to most people's daily life because the heating of the home is instead done by a furnace or a heating stove, and cooking is instead done with a kitchen stove/range alongside other home appliances; thus many homes built in the 20th and 21st centuries do not have hearths. Nonetheless, many homes still have hearths, which still help serve the purposes of warmth, cooking, and comfort.
Colonel Sir Benjamin Thompson, Count Rumford, FRS, was an American-born British military officer, scientist, inventor and nobleman. Born in Woburn, Massachusetts, he supported the Loyalist cause during the American War of Independence, commanding the King's American Dragoons during the conflict. After the war ended in 1783, Thompson moved to London, where he was recognised for his administrative talents and received a knighthood from George III in 1784.
A chimney is an architectural ventilation structure made of masonry, clay or metal that isolates hot toxic exhaust gases or smoke produced by a boiler, stove, furnace, incinerator, or fireplace from human living areas. Chimneys are typically vertical, or as near as possible to vertical, to ensure that the gases flow smoothly, drawing air into the combustion in what is known as the stack, or chimney effect. The space inside a chimney is called the flue. Chimneys are adjacent to large industrial refineries, fossil fuel combustion facilities or part of buildings, steam locomotives and ships.
The Franklin stove is a metal-lined fireplace named after Benjamin Franklin, who invented it in 1742. It had a hollow baffle near the rear and relied on an "inverted siphon" to draw the fire's hot fumes around the baffle. It was intended to produce more heat and less smoke than an ordinary open fireplace, but it achieved few sales until it was improved by David Rittenhouse. It is also known as a "circulating stove" or the "Pennsylvania fireplace".
A stove or range is a device that generates heat inside or on top of the device, for -local heating or cooking. Stoves can be powered with many fuels, such as natural gas, electricity, gasoline, wood, and coal.
Wood fuel is a fuel such as firewood, charcoal, chips, sheets, pellets, and sawdust. The particular form used depends upon factors such as source, quantity, quality and application. In many areas, wood is the most easily available form of fuel, requiring no tools in the case of picking up dead wood, or few tools, although as in any industry, specialized tools, such as skidders and hydraulic wood splitters, have been developed to mechanize production. Sawmill waste and construction industry by-products also include various forms of lumber tailings. About half of wood extracted from forests worldwide is used as fuelwood.
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.
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.
A fireplace or hearth is a structure made of brick, stone or metal designed to contain a fire. Fireplaces are used for the relaxing ambiance they create and for heating a room. Modern fireplaces vary in heat efficiency, depending on the design.
Home roasting is the process of roasting coffee from green coffee beans on a small scale for personal consumption. Home roasting of coffee has been practiced for centuries, using simple methods such as roasting in cast-iron skillets over a wood fire and hand-turning small steel drums on a kitchen stovetop.
The Benjamin Thompson House is a historic house museum and National Historic Landmark at 90 Elm Street, in the North Woburn area of Woburn, Massachusetts. It is significant as the birthplace of scientist and inventor Benjamin Thompson (1753–1814), who became Count Rumford of the Holy Roman Empire as well as Sir Benjamin Thompson of the United Kingdom. His birthplace was designated a National Historic Landmark in 1975 in recognition of Rumford's scientific accomplishments, which notably include the development of the Rumford fireplace, a fireplace design that was significantly more efficient at retaining heat in the house than older and larger fireplaces.
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.
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%.
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 Kachelofen. 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 eventually evolved into modern systems.
A flue-gas stack, also known as a smoke stack, chimney stack or simply as a stack, is a type of chimney, a vertical pipe, channel or similar structure through which combustion product gases called flue gases are exhausted to the outside air. Flue gases are produced when coal, oil, natural gas, wood or any other fuel is combusted in an industrial furnace, a power plant's steam-generating boiler, or other large combustion device. Flue gas is usually composed of carbon dioxide (CO2) and water vapor, as well as nitrogen and excess oxygen remaining from the intake combustion air. It also contains a small percentage of pollutants such as particulate matter, carbon monoxide, nitrogen oxides and sulfur oxides. The flue gas stacks are often quite tall, up to 420 metres (1,380 ft), to increase the stack effect and dispersion of pollutants.
A convection heater, also known as a convector heater, is a type of heater that utilizes convection currents to heat and circulate air. These currents move through the appliance and across its heating element, using thermal conduction to warm the air and decrease its density relative to colder air, causing it to rise.
The Rumford roaster is an early cast iron oven, invented by Sir Benjamin Thompson, Count Rumford, around 1800. It was part of his development of the kitchen range, which gave more control of the cooking and saved fuel. He published his research in 1805.
A fireplace insert is a device that can be inserted into an existing masonry or prefabricated wood fireplace. Fireplace inserts can be fuelled by gas, wood, electricity, coal, or wood pallet. Most fireplace inserts are made from cast iron or steel. Fresh air enters through vents below the insert, where it then circulates around the main chamber and back into the room. Separate adjustable air vents control airflow into the firebox which then exits through a chimney. Typical fireplace inserts have insulated glass doors that allow the fire to be viewed while closed, improving its heat output and fuel efficiency while maintaining ambiance of a traditional fireplace. Air is directed across the interior surface of the glass to prevent a build-up of ash.
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 rocket mass heater (RMH), also known as rocket stove mass heater, is a form of slow-release radiant heating system, designed to primarily heat people and secondarily to warm areas in line of sight around it. Variations of RMH can also be extended for the functions of cooking, heating water, and producing warm air for distribution.