- Fireplaces are heated not only with wood
- Solid fuel
- Pellet fuel
- Gaseous fuel
- Electric fireplace
The open portal of the firebox, flames rushing about in it, licking the logs, necessarily crackling during the combustion process – this is the popular idea of the fireplace, which has been repeatedly described by artists, writers and directors. Such a fireplace looks beautiful, but not entirely functional, since for heating purposes it is enough for only one room, and it is not easy to equip and maintain. The selection of the optimal fuel can greatly affect the situation – let’s figure it out.
Fireplaces are heated not only with wood
The first thing that the future owner of the fireplace needs to know is that the type of fuel is determined by its design. Open fireboxes are designed only for wood fuel, closed ones – for fireboxes with wood, coal, fuel briquettes and peat. Fireplaces that consume gaseous, liquid fuels and pellets are equipped with specially designed burners. Finally, there are electric fireplaces and bio fireplaces – the former heat the room well, and the latter perfectly imitate a real fireplace with a live flame, although they do not heat.
We investigate the types of fuel for fireplaces – this information will allow the homeowner to buy a fireplace with a set of really necessary characteristics, and not one that is profitable to sell to the seller.
Fireplaces designed for firewood or coal heating are a rather bulky structure, consisting of a portal, a firebox and a complex chimney.
For heating a wood-burning fireplace, use dry hardwood, the most suitable are aspen, alder, oak, beech, plum and ash logs. During combustion, softwood produces a lot of soot, has a low calorific value, crackles and scatters sparks over considerable distances, which can damage the flooring and cause a fire. Birch logs have a high calorific value (about 20% higher than other types of wood), but they form a lot of soot and clog the chimney. Burning aspen and alder wood in the fireplace, you can, on the contrary, burn out the soot deposited on the walls of the chimney channel. The calorific value of wood, provided that the thickness of the logs does not exceed 10 cm, will be about 3300 kcal / kg – the thicker the logs, the worse they burn and generate less heat.
To burn lignite and hard coal in a fireplace, it is imperative to equip the firebox with a grate and a lid that covers the firebox. The calorific value of brown coal is 4700 kcal / kg, coal (depending on the grade) – 600–7200 kcal / kg. Fossil coal with a combustion temperature exceeding 1500 ° C is not suitable for a fireplace insert. Before lighting the fireplace with charcoal – make sure that this model allows its use!
Peat is close in its calorific characteristics to wood – 3000 kcal / kg (lump, 30% moisture) and 4000 kcal / kg (briquette). When choosing this type of fuel, it should be borne in mind that peat gives a lot of ash when burned.
Fuel briquettes of various shapes, made in the factory from pressed sawdust or wood dust, have a high density (about 1000 kg / m3) and low humidity (no more than 10%), which makes it possible to obtain a calorific value during their combustion, almost equivalent to that of coal – about 5000 kcal / kg. Some brands of fuel briquettes are impregnated, which allows obtaining a flame of a certain color during their combustion. It should be noted that fuel briquettes are more suitable for fireplaces with a closed firebox, since when the firebox is open, they quickly burn out.
Without exception, all solid fuel fireplaces need a chimney of the required length or equip a short chimney channel with a forced exhaust system. Therefore, regardless of the type of fireplace and the materials from which the portal and firebox are made (brickwork, cast iron or steel cassette), they cannot be installed in an apartment. Theoretically, wood-burning fireplaces can be installed in an apartment on the top floor of the house, since it will be possible to bring the chimney to the roof, but it is impossible to obtain the appropriate permits for this. In case of violations in the design of the chimney, smoke from the fireplace can enter the room – solid fuel fireplaces can be heated only under constant control.
Pellet fireplaces are equipped with a bowl-shaped burner with a lattice bottom and walls, into which wood pellets (pellets) are fed in portions from the fuel hopper, and forced air is supplied from below. The calorific value of pellets is about 4500 kcal / kg, their dosed input into the firebox, combustion control and the intensity of air supply are automatically regulated, which allows you to control the operation of such a fireplace remotely. By their design, pellet fireplaces are similar to boilers operating on this fuel – the difference is, by and large, in the presence of a transparent firebox cover, which allows you to observe the play of flame.
A pellet-burning fireplace needs a simplified chimney design, more like a cooker hood. Such fireplaces can be installed on any floor, some models are equipped with heat exchangers that allow heating the coolant for air or liquid heating systems, they have a high efficiency – about 90%. The disadvantage of pellet fireplaces is their rather high cost, for example, a 10 kW fireplace costs about 52,000 rubles.
A fireplace with an atmospheric gas burner, designed for natural (methane) or liquefied (propane-butane) gas, makes it easier for owners to prepare fuel, as well as periodically clean the firebox and chimney from ash and soot. The combustion process in a gas fireplace is controlled by an automatic system, the combustion temperature is controlled by a thermostat. Such a fireplace can be installed in an apartment and on any floor of a private house, having received the necessary permits from supervising government agencies – its design does not need a full-fledged chimney, a conventional hood brought out to the street will be sufficient.
The flame in the firebox of a gas fireplace is not as intense and bright as in a solid fuel fireplace, it has a bluish tint. The wood-burning masonry in it is imitated by ceramic “firewood”, which becomes red-hot as it heats up – studying the photo of fireplaces, it is quite difficult to distinguish gas from wood from the first time. Despite the high calorific value of gas fuel (8500 kcal / m3), The efficiency of fireplaces in this group is usually 50%, and then only in the case of a closed firebox. An infrared gas burner will increase the efficiency of a gas fireplace – the flame in such a burner is small, but it heats up to 800 ° C a ceramic grate located on top that generates infrared rays. Fireplaces with an infrared burner are well suited for use in climatic zones characterized by low winter temperatures (below -30 ° C), as well as for heating large rooms.
Electrical appliances of this group are intended to a greater extent for decorating rooms than for performing heating functions, although an electric fireplace is able to create an optimal temperature in a room up to 25 m2. Externally, an electric fireplace resembles a portal of a wood-burning fireplace, made of cast iron (classic style) or glass and metal (high-tech). Modern models of electric fireplaces are equipped with LCD screens and a sound system, which allows you to visually display a burning flame in a firebox with wood and create the necessary sound accompaniment of the combustion process.
Among all existing types of fireplaces, the biofireplace is the latest development – only this heater, if there is a real flame in the firebox, does not need any extractor hood.
The main element of the biofireplace is a stainless steel block into which ethanol is poured (containing special additives of ethyl alcohol). When burning, bioethanol does not emit any soot or soot, there are no odors – the products of combustion are water in the form of steam and carbon dioxide. The biofireplace body is usually made in a high-tech style. In this case, the sizes can be very different, from tabletop models to floor-standing corner, wall-mounted or free-standing ones. If necessary, the bio-fireplace block module can be built into the existing portal of the wood-burning fireplace, camouflaging it with ceramic “wood” or stones – before lighting, make sure that the chimney channel is completely closed with a damper, since the intensive air movement will extinguish the flame in the bio-fireplace.
We are not talking about the thermal performance of bio fireplaces – they are intended solely for decorative purposes. It is possible to install such a fireplace in any room, however, it is required to put a base made of non-combustible materials of low thermal conductivity under it, since the body of the biofireplace will heat up. The flame in the biofireplace should not be perceived as something safe – it is real, which means it can cause burns and cause a fire if handled carelessly.