Dictionary of Terms The Solid Fuel Dictionary

Manual or automatic device to control the quantity of air supplied for combustion

Secondary air admitted to a glass-fronted fire so as to be pulled down the inner surface of the window and help prevent staining.

A measure of the light reflectivity of a surface.  Light colours will reflect light (including the infra-red light associated with heat), dark colours will absorb.

Anthracite is a hard, compact variety of mineral coal formed at great depth over some 300 million years.  It has a high lustre, the highest carbon count and contains the fewest impurities of all coals.

Ash is essentially all compounds that are not considered organic or water.  The incombustible residue left when fuels have burned.

A removable receptacle shaped to receive the residue falling from the firebed

An enclosed chamber designed to receive the residue or the ashpan

Baffle Plate or 'throat plate'- a metal r ceramic plate fitted above the firebed of an appliance to slow the passage of gasses and so increase efficiency.

The quantity of glowing embers which ensures ignition of the test fuel to be charged.

Vessel in which water is heated, intended for fitting in or forming an integral part of a solid fuel appliance, whether or not water actually boils, ie reaches 100degC.

Space within a boiler which contains water

Part of the appliance which supports the fire-bed and through which the residue falls into the ashpan or ashpit and through which combustion air and/or combustion gases may be drawn

A type of open fire, usually inset or occasionally freestanding, with a barbecue cooking facility, fitted into a chimney breast either out of doors or indoors as part of a fireplace or kitchen units, common in Namibia, Botswana, Zimbabwe and South Africa.  Some Braai also have convective heat.

Powdery coke waste.

The reduction in the mass of fuel per unit of time, typically expressed as kg per hour.

See Kennel

A colourless, odourless, highly poisonous gas, CO, formed by the incomplete combustion of carbon or a carbonaceous material, which includes all solid fuels.  Carbon Monoxide is denser than air, and so sinks, and very readily combines with hemoglobin in blood, thereby preventing the blood from taking up oxygen.  Carbon monoxide poisoning causes dizziness, weakness, pale skin with blue-ish lips and can rapidly be fatal if the victim is not supplied with fresh air.

In chemistry, a catalyst is a substance that decreases the amount of energy needed to initiate a chemical reaction without itself being changed at the end of the reaction.  Catalytic converters in solid fuel appliances are generally a ceramic mesh doped with heavy metals such as iridium or osmium through which gases from the fire pass and which serves to reduce the temperature at which carbon is converted into carbon monoxide and on into carbon dioxide.

The door which covers the refueling opening

The whole structure encasing a flue.

The freestanding part of a chimney above the building it serves.

The carbon-laden mineral formed over c50 to 400 million years by the decay of woody material under pressure.  The word originally meant any lump of fuel, whether mineral or wood, hence the word 'charcoal'.

The solid residue of impure carbon obtained from bituminous coal and other carbonaceous materials after removal of volatile material by destructive distillation.  It is used as a fuel and as a reducing agent in making steel.

Air supplied to the firebox, which is entirely or partially used to burn the fuel

Device for adjusting the primary and/or secondary air according to the type of fuel burned

Mechanism for setting the primary and/or secondary air in accordance with the burning rate required

Compounds in gaseous form produced inside an appliance when fuel is burned

The transmission of, typically heat or electricity, through a material.

The motion of warm material that rises, cools off, and sinks again, producing a continuous circulation of material and transfer of heat.  Enclosed heating appliances transfer heat mainly by convection.

The cord is a unit of dry volume used in Canada and in the United States to measure firewood.  One cord is defined as 128 ft³, corresponding to a woodpile 8 ft wide × 4 ft high of 4 ft-long logs.

'Dry Ash Free'

Mechanism to change the resistance to flow of the combustion gases

Process of clearing a fuelbed and discharging residue into the collecting receptacle

Device to agitate or disturb the ash to facilitate its removal from the firebed: NOTE It may also be used to change the bottomgrate operating position on some appliances.

Grating or plate fitted at the front of the firebox opening to prevent spillage of fuel and ash or to change the firebox capacity, or both

Hot water system in which stored domestic hot water is heated directly by hot water circulating from the boiler

Inlet device for admission air downstream of the firebed, enabling the flue draught to be controlled

Ratio of total heat output to total heat input during the test period expressed as a percentage

The capacity to do work or vigorous activity.

A hinged plate constructed so as to be able to be moved to cover the fuel, to stop or to restrict combustion.  Occasionally used on open fires.

The rapid release of heat energy with visible light, typically by the oxidation of fuel.

The brick or concrete rear part of an open fire.

The slotted support on which fuel is burned.

Fuel contained in the firebox

That part of the appliance in which fuel is burned

Aperture in the firebox through which the appliance may be fuelled

Door through which the fire may be viewed and which may be opened to allow refueling of the firebed

The whole of the architectural element enclosing a heating or cooking fire.

The hole or shaft inside a chimney through which waste gases pass to the atmosphere.

Differential between the static air pressure in the place of installation and the static pressure at the flue gas: measurement point

Fitting which allows for variations in size and shape of the flue components

Duct through which flue gases are conveyed from the flue spigot of the appliance into the chimney flue"

Mass of flue gas drawn off from the appliance per unit of time

Temperature of the flue gas at the specified point in the measurement section

Gaseous compounds leaving the appliance flue spigot and entering the flue gas connector

Method of determining the performance of a heating appliance by determining the temperature and chemical composition of the waste gasses being lost into the flue, from which the efficiency and heat output can be estimated.

Integral part of the appliance for connecting the flue gas connector thus permitting the deliberate escape of: products of combustion into the chimney flue

Integral part of the appliance for connecting the flue gas connector thus permitting the deliberate escape of: products of combustion into the chimney flue

That part of the appliance designed to convey combustion gases from the firebox to the flue spigot

Grating or plate fitted at the front of the firebox opening to prevent spillage of fuel and ash or to change the firebox capacity, or both

Fuel store integral with the appliance from which fuel is fed to the firebox

Device for controlling the size of the firebed

Fuel contained in the firebox

See Bottomgrate

A form of energy associated with the motion of atoms or molecules and capable of being transmitted through solid and fluid media by conduction, through fluid media by convection, and through empty space by radiation.

Quantity of energy, which the fuel provides to the appliance

Quantity of useful heat released by the appliance

The type of coal normally supplied for domestic use.  This will vary from place to place.  In Britain and Ireland it is Bituminous coal, in the USA it is anthracite.

Hot water system in which stored domestic hot water is heated by a primary heater through which hot water from: the boiler is circulated without mixing of the primary (heating) water and the stored domestic hot water

Enclosed area forming part of the appliance, but not connected directly to the fuel charging area, in which fuel is: stored prior to it being physically transferred by the user to the fuel charging position

Enclosed area forming part of the appliance, but not connected directly to the fuel charging area, in which fuel is stored prior to it being physically transferred by the user to the fuel charging position"

German type of Masonry Stove

A light, clean, fine-grained bituminous coal.  The term may be a corruption of "candle" because it burns without smoke.  There are deposits in North America, UK, Poland, South Africa and Australia.

A soft, brownish fuel material, intermediate between peat and bituminous coal, formed over c4000 years.

Type of enclosed roomheater which stores heat in a brick labyrinth.  Well-designed masonry stoves may only need firing for an hour or so to provide 24 hours of heating.

German= Kachelöfen
Russian= Petche

See Masonry Heater

Limiting water pressure up to which the boiler of an appliance can be safely operated

Generally, appliance capable of burning both mineral and wood fuels.

Generally, appliance capable of burning both mineral and wood fuels.

See Multi-Fuel

Total heat output of the appliance quoted by the manufacturer and achieved under defined test conditions when: burning the specified test fuel

Device supplied with the appliance for handling movable, adjustable and/or hot components

Peat is woody material which has semi decomposed over about 1000 years.  It is the earliest stage in the formation of coal.

Russian Type of Masonry Stove

See Petroleum Coke

A solid fuel made from petroleum residues.  High in sulphur and low in protective ash it burns with intense heat, but can damage appliances and cause high levels of atmospheric sulphuric acid.

Combustion air, which passes through the fuel bed

A general term for the organic substances formed when wood partially burns.

The decomposition of a chemical compound by heat.  The chemical decomposition of organic materials by heating in the absence of oxygen or other reagents.  'Complete' pyrolysis, leaving only carbon as the residue, is carbonization.

Any high-temperature thermometer, especially optical pyrometers which estimate the temperature of an object too hot to make contact with by analysing the visible and non-visible light emitted.

The emission and transmission of energy through space or through a material medium, or the radiated energy itself.  Heat radiation travels in straight lines, requires no medium (it can travel through a vacuum) and diminishes by the square of the distance travelled.

Fuel of commercial quality listed in the appliance manufacturer's instructions, and shown to achieve the claimed: performance when tested in accordance with a Standard

Ability of the fire to re-ignite existing or newly charged fuel after a defined burning period without external: assistance

Period of time for which the combustion may be maintained in the appliance with a single load of fuel, without: intervention by the user

Ashes, including combustibles, which collect in the ashpit

See Riddling Mechanism

Device to agitate the firebed and so dislodge ash.

The preferred term for 'stove' in British Standards.

Air supplied for the purpose of completing the combustion of gases leaving the fuel bed

Powdery waste coal.

Heat output achieved during the test period under slow combustion conditions

Ability of an appliance to continue operating at a low burning rate for a specified minimum period without any: input of fuel and without any interference with the combustion process, in such a manner that the firebed can be: recovered at the end of this period

Solid particles suspended in gas.

Natural or manufactured solid mineral fuels, natural or manufactured wood logs and peat briquettes

Coal, lignite, coke and fuels derived from these

Heat output provided by convection and radiation to the room

See Chimney Stack

Mechanism to divert the path of the heating gases and/or change the combustion air opening cross section during: the ignition period

Stage at which values to be measured in successive equal periods of time do not exhibit significant change

An appliance which heats one space, either the individual room-space it is in (as with heating stoves), or just its own space (as with a cooking stove).  Central-heating devices, whether boilers or hot-air heaters, are not 'stoves' in that they heat not one but many spaces, yet they also emit heat into the space they themselves are in and are therefore more accurately described as 'stoves with central heating'.  The Old English stofa meant any individual enclosed space, such as a room, and is still occasionally used in that sense, as in 'stoved in'.  Until well into the 19th Century 'stove' was used to mean a single heated room, so that Joseph Banks' assertion that he 'placed his most precious plants in the stove' or René Descartes observation that he got 'his greatest philosophical inspiration while sitting inside a stove' are not as odd as they seem.

Fuel of commercial quality being characteristic of its type to be used for testing appliances

Temperature sensitive device which automatically changes the combustion air inlet cross-sectional area

See Baffle Plate

Rate of useful heat released by the appliance

See Peat

Pressure to which all waterways of the test appliance are subjected

Heat output to water averaged during the test period

The white-ish flocculent powder left when wood has disintegrated while burning.  Wood Powder is not ash, and, if kept hot enough for long enough can be made to burn.  True wood ash is brown-ish and relatively dense, sand-like.  High outputs of Wood Powder indicate a poorly-designed fire

All the surfaces of an appliance designed to transmit heat to the surrounding atmosphere.  All external surfaces of a heating boiler including the flue gas connector in accordance with EN standards are classified as working surfaces because they are designed to transmit heat to the room in which the appliance is installed.