The 5 best solid fuel boilers of different types
If you are having difficulty choosing a solid fuel boiler for your cottage or summer house, then reading this article will make your task easier. The presented material contains brief information on the operation of such equipment, lists the best manufacturers in our opinion and the most reliable models.
The selection of products was made on the basis of reviews, opinions and assessments of users posted on various resources on the Internet. All information taken from public sources. We do not cooperate with manufacturers and brands and do not encourage the purchase of certain products. The article is of informational character.
Boilers
Boilers are devices designed for heating buildings and structures of different purposes: individual and multi-family houses, cottages, industrial facilities, industrial workshops, garage boxes, etc.д. The variety of spheres of universal devices requires a wide range of power: from 10 to 1000 kW. Their operating principle is based on combustion of a variety of fuels. According to this criterion, they are divided into. Solid fuel boilers that burn wood, coal, briquettes, etc.д.;. pellet;. gas;. diesel;. electric. combined. In addition, depending on the functionality of boiler units can be. single-circuit. aimed only at heating. two-circuit. heating for hot water supply. by the way of installation boilers can be wall and floor. With a full catalog of domestic and foreign equipment can be found on our website Magazin-Pechi.ru.
The company Shop Furnaces is actively developing its Boiler Equipment division. Already since 2012, it has become clear that our customers are not only interested in buying heating boilers, they are interested in a whole range of services. We sell wood boilers, coal boilers, pellet boilers, perform chimney installation, turnkey heating installation. That is why we have created our own Department of installation of climatic equipment, specialists who are always happy to help you.
An important advantage of such boilers is sometimes their energy-independence, when in the construction there are no devices that require electricity, even mechanical thermoregulators. often it concerns domestic manufacturers, who know firsthand about power outages in rural areas and take this fact into account in the scheme of boilers. However, do not forget that modern heating systems, even with a solid fuel boiler as a heat source, operate more stably in the presence of a circulating pump, and it does not work without power, alas. So it is recommended to have a reserve power supply station in case of power supply problems, but often the solid fuel boiler is excluded from the list of power-consuming devices.
Material of the heat exchanger of the solid fuel boiler: cast iron or steel
Solid fuel boiler is associated with something bulky and heavy, as its heat exchanger is often made of cast iron. Boiler manufacturers use this material for its durability, high corrosion resistance (wear of cast iron heat exchanger in the normal mode is 0,1-0,2 mm per year, so with a wall thickness of 5 mm it will last for twenty years), resistance to high temperatures (when burning coal only cast iron heat exchanger can withstand a burning temperature of 900 degrees C), temperature deformations are not characteristic for it.
The disadvantages of boilers with cast iron heat exchangers include their heavy weight, which complicates transportation, during which the equipment also can not drop, hit. cast iron is brittle and cracks on a sudden impact. Cracks will also appear if cold water is spilt on the hot heat exchanger or if the boiler is fed with too cold water. The difference in temperature between the flow and return flow temperatures of over 50 degrees Celsius can be fatal for the cast iron heat exchanger, even if the micro cracks are not initially visually visible. Some modern products of eutectic (ductile) cast iron work successfully at low temperatures on the boiler inlet, it exceeds the elasticity of conventional gray cast iron by 30% on average and makes it possible to operate the boiler in low-temperature operation.
Another solution for low-temperature operation of solid fuel boilers can be the use of a buffer vessel in the boiler system.
At the same time, cast iron heat exchangers consist of sections and can therefore be repaired. Sections are replaced, fastened with screws with heat-resistant gasket and sealant. Thanks to the sectional nature, the cast iron boiler can “grow” with the house. For example, by adding to the house a large workshop, or conservatory, you can not buy an additional boiler, but only add internal sections, thereby increasing the boiler capacity to the desired.
The power of household boilers is calculated by the formula “1 kW per 10 m² of heated area”, i.e. the house of 200m² will need a boiler with the power of 20 kW.
Boilers with steel heat exchangers are similar in capacity, but their designs are more diverse and they are usually cheaper, which makes them a frequent source of heat in solid fuel boilers.
The lightness of the steel heat exchanger and its welded construction are both advantages and disadvantages in the solid fuel boiler. To transport, unload. simpler, but the temperature extremes of such a boiler takes worse, at overheating the heat exchanger can deform, welds. leak and sometimes the wall of the heat exchanger can also burn out.
Such situations most often occur in case of power failure and in systems with forced circulation. In this case, the boiler continues to heat, and the circulation pump does not rotate, does not remove heat from the boiler and overheating occurs. Uninterruptible power sources help, but in 50% of cases do not work, it is best if there is an automatic switch to a diesel power plant. The most effective way to protect the solid fuel boiler from overheating in case of accidents with electricity is considered a short circuit with gravitational circulation, which is a section of large diameter pipes, where the boiler heated coolant will be during the accident.
What is burning in the solid fuel boiler?
Brown, black or anthracite. In these three types of coal contains the amount of energy required to heat the heat carrier, in the brown. the smallest, in anthracite. highest. Most often black coal is used as fuel. In general, the burning of coal is about three times more efficient than burning wood, when burning it emits 5000 to 8000 kcal/kg, while the wood. from 1500 to 2500. This is a plus of coal firing. However, to store coal you need a special room, coal emits coal dust, often contains impurities that reduce its efficiency during combustion, it is not easy to ignite, and when poured in a layer thick half of the furnace, it may not burn, and sintered on the grate.
Coal heating requires the constant presence of service personnel, and this should be taken into account when choosing a boiler with this fuel source. Boiler with automatic coal supply can solve this problem.
Toy briquettes as source of heat can be used in the same boilers, where you can burn coal, firewood open. The calorific value of toa is quite low. They produce smoke with an unpleasant odor, a lot of ash, and they crumble during storage, worsening the efficiency of combustion, but if no other sources can be found, it can be used. Without the participation of the stoker such boilers work in an industrial version, on a milling toe with a screw feeder, drying chamber and in this kind of boiler capacity can reach and 10 MW
In regions with large areas of wild forests firewood becomes the most economical and easily accessible fuel for boilers.
You can also heat the boiler with apple, cherry, pear trees, and the calorific value of such firewood is quite high, but it is difficult to find them in large quantities, and the logs are badly split and knotty, not stacked tightly in the furnace. Poplar wood burns quickly and hot, but there is little heat from it, its wood is loose.
Firewood for the boiler must have a humidity of no more than 15-25%, so immediately after cutting them do not use, for their storage should be provided with a place and heat better wood, dried naturally for 2-3 years, or after forced drying.
Boiler furnaces, depending on the output, allow the use of up to 70-80 cm long logs, although the most common size is 25-40 cm. Approximately half the fire chamber is loaded immediately with wood, ignited, and the logs are added as needed. During the firing process, the billets need to be tapped a few times to provide extra air for even burning. All solid fuel boilers do not work without an air supply, so the space for them should be ventilated, and the chimney for better draft should be long. 6-7 м
To increase the time interval between putting firewood into the boiler, which is especially important at night during the winter, and to reduce the costs of the stoker, engineers have created and successfully used boilers with pyrolysis method of wood combustion. In contrast to the direct method, when the heat from burning wood is only partly spent on heating the heating medium, and mainly flies into the pipe, in pyrolysis burns the gas released by the combustion of wood.
The two-chamber system of fuel combustion makes it possible to achieve the boiler efficiency of 85-90%, and although this method of combustion is acceptable for both coal and wood, it is most effective when using dry wood, not more than 20% moisture. Time of laying the wood of both soft and hard varieties in such boiler is 5-6 hours, and under good conditions: dry fuel, stable air supply to the combustion chamber, proper thermal insulation of the house can be even 10 hours. When using wet wood a large amount of water vapor is released, and this is fraught with the formation of soot and tar, poor thermal conductivity of the boiler or its fading. If the pyrolysis process flows correctly the wood burns almost without ash, the smoke from the chimney is colorless, and the coolant is quickly heated to the optimal 60 degrees C.
There are also combination boilers, when 80% of the wood burns in the pyrolysis mode and 20% of the wood burns in the pyrolysis mode. in the mode of the usual solid fuel boiler.
The disadvantages of pyrolysis boilers are their high cost compared to conventional solid fuel boilers, increased requirements to the dryness of wood, the lack of possibility of automatic fuel supply, and work only in heating mode, such boilers are not double-circuit.
No major European building exhibition of boiler equipment is not complete without the demonstration of equipment operating on pellets. wood fuel pellets. This fuel began to be used in the 80s of the twentieth century and now boilers to work on them are in the range of almost all leading manufacturers of solid fuel boilers. Automation of fuel loading process in the combustion chamber, low humidity and, accordingly. The high heat capacity of pellets, coupled with the small size for storage, transportation makes them very convenient and effective, especially in areas where woodworking is developed. Burning pellets of “Premium” grade produces no more than 1% of ash, “Standard” grade. The fuel is not more than 3%, so it is also very environmentally friendly.
Chips, bark and sawdust as fuel have long been used in boilers, but to use them effectively, boilers of specific design should be chosen, they have a layered combustion chamber, a rotating grate or other parts and techniques that allow to burn completely both coarse wood, like chips, and dispersed wood, like sawdust. often such boilers are used in industrial boiler houses.
Modern solid fuel boilers have in their composition temperature controllers, blowers, control devices, and if desired on their basis you can build a comfortable, comfortable boiler house in areas where there is no gas supply. Such boilers are cheaper than electric ones in operation and can often operate as energy-independent units.
Boilers in the online store ➦ Furnace Shop. ☎: 7(495) 902-57-82. Sandwich chimneys 1 mm thick from the manufacturer. Low prices. High quality. Delivery in Russia.
To order installation and installation of chimney for baths, cottages, houses CALL ☎: 7(495) 902-57-82.
Automatic pellet boiler
Automatic pellet boilers allow to increase significantly the comfort in use of heating system thanks to automatic fuel supply, namely pellets inside the combustion chamber directly from pellet storage.Automation involves minimal intervention in the boiler, because the whole process is fully controlled by the system. Thanks to the automatic supply of pellets in the boiler burner minimizes the need for constant bookmarking of pellets. At the same time, it is worth noting that with a minimum amount of fuel, the user can carry out a manual laying of pellets, then somewhat save their use.
Pellet boilers today have different modifications and can be divided into the following types:
Only pellets are used as fuel;
The equipment has a removable type grate, which makes it possible to use wood, coal and in some cases briquettes as fuel;
Equipment of combined type, which has several furnaces, as well as a removable burner. The device of this type is often used as a standard variant of a solid fuel boiler.
These types of equipment have different fuel consumption and, accordingly, different power indicator. Boilers for pellets have an efficiency from 87 to 97 percent. The design on pellets is much more environmentally friendly than similar equipment, which operates on coal.
Fuel supply is automatic, and in addition there is the possibility to program the modes of operation. Switching on, as well as turning off the burner is carried out in automatic mode. The boiler has an impressive protection against fires and any breakdowns, which allows you to make heating as safe as possible.
Automatic pellet boiler in the online store ➦ Shop stoves. ☎: 7(495) 902-57-82. Sandwich Chimneys 1mm thick from the manufacturer. Low prices. High quality. Delivery within Russia.
To order installation and mounting of the chimney for the baths, summer cottages, houses CALL ☎: 7 (495) 902-57-82.
Fuel requirements
Although so long boilers can be stoked with wood or wood pellets, the duration of their combustion will not be 7 days, and depending on the characteristics of fuel. 12-30 hours. High-quality pellets can provide up to 72 hours of heating, t.е. up to 3 days.
To ensure the duration of combustion up to 7 days it is necessary to use coal. Optimal in terms of price-quality ratio. coal. The greatest heat has an anthracite, but the cost of such coal. 8000-8500 per ton, which is not cheap. Also, an excellent heat output and duration of combustion has a charcoal (especially hardwood. grade A).
Solid-Fuel Boiler Presentation CGI animation
The worst option is widespread and most affordable brown coal, which burns at best 3-4 days and has a much higher ash content compared to other varieties.
In addition, it is better to heat with low-smoked (type 31 or 32) and low-ash (up to 15%) coal to avoid the extra “trash” and reduce the efficiency.
Pellet boilers with automatic fuel supply Combustion duration of 7 to 30 days due to the storage hopper
Solid fuel heating boilers
Most cottages, country houses and cottages are located in areas where there is no centralized engineering network. For the arrangement of the heating system, you can use several solutions, the choice of which depends on the frequency of residence and budget of the owner. Often tenants heat rooms with electric equipment, but its use is not always effective, and the cost of utility bills is quite high. For this reason, many make a choice in favor of solid fuel, which includes coal, wood, pellets and other varieties.
Solid fuel boilers are a broad category of devices that operate under the same scheme as the classic wood stove. Energy release occurs due to the combustion of fuel, then the heat comes into the room. In our store you can order a solid fuel boiler of the desired capacity with delivery in the city and region.
Solid fuel boilers
There are still places in the country where there is no electricity and gas. Mainly these are garden associations. How to organize the heating of the house in such places? To solve the problem you need to buy a solid fuel boiler. These devices heat the room with firewood or briquettes. Solid fuel boilers can be installed in any home, even with gas and electricity. In a holiday home heating system, which includes such a device, will feel as comfortable as in an apartment.
Solid fuel boilers
Solid fuel boilers are equipment for efficient heating of a country house and heating water for household needs. The operation makes it convenient to set the temperature of the coolant and DHW water, and in some models and the speed of the fuel material.
Design and operation of solid fuel boilers
The design of the solid fuel boiler includes:
- the stoking chamber where the solid fuel is placed;
- A heat exchanger where the heating medium and water are heated
- Ash box, where the ash from the spent heating material is accumulated.
When burning firewood, coal or coke, the heat generated goes into the heat exchanger. It heats the water and distributes it over the radiators. Together with a solid fuel boiler it is important to install a condenser tank with thermal insulation. When the temperature of the heating medium is at the set level and the fuel has not yet burned through, the heated water flows into the condenser. There it will not cool down, because the tank has good insulation, and will enter the heating system when needed.
Pyrolysis boilers
Their design differs in the presence of an additional chamber, which is necessary for the combustion of pyrolysis gas, which is formed during the operation of the boiler. It is located in the upper part.
Pyrolysis wood boilers require not only the fuel material, but also electricity, which goes to work the fan. It draws in air used for pyrolysis gas combustion.
It is worth noting that the price of pyrolysis boilers exceeds the cost of a traditional heating boiler. At the same time during its operation the heat loss is reduced and the efficiency level is close to 90.
Long combustion boilers
Characterized by a large combustion chamber. For example, you can compare the models of solid fuel boilers of the well-known manufacturer Buderus Logano. In solid fuel boilers long combustion series G221 combustion chamber size 57 cm, and conventional boilers of the same manufacturer from 30 to 53 cm. The capacity of the first is from 20 to 40 kW, and the second from 12 to 45 kW.
And one more remark: during the operation of boilers on the long combustion wood it is necessary to put the fuel material into the furnace less often, which makes maintenance much easier.
The material of the heat exchanger
Cast iron can withstand high temperatures of air heating; they rarely corrode. The material is nonplastic, so a sharp change in temperature may cause cracks in the product, which can later lead to corrosion. The service life of such a heat exchanger is usually about 20 years.
Steel ones are made of plastic material. They are insured against micro-cracking if the level of heating fluid varies. Because of the condensate that appears on the walls of the boiler during operation, rust can occur. Relatively inexpensive compared to cast iron heat exchangers.
Copper is smaller in size than cast iron or steel products, so the size of the heating boiler is also small. Thermal conductivity of material is higher, than analogues of other materials. Practically not affected by corrosion.
Popular manufacturers of solid fuel boilers
At the online store VseInstrumenty.boilers for heating with solid fuel from foreign producers, like German company Buderus, Czech brand Protherm, Italian brand SIME. Presented products have high quality of manufacturing. The manufacturers provide warranty on goods for up to 24 months.
Order equipment in online store VseInstrumenty.ru online shop right now! You will need just a few minutes to place your order. The goods will be delivered to the specified location in the short term. Our company provides services and installation of boilers for heating. If you need these works, specify it to the manager when you make a purchase by calling: 8-800 333 83 28.
Calculation of minimum required boiler output
Proper power calculation will allow you to live through any frosts without worries and always have warm water in sufficient quantity. The minimum required power is calculated on the basis of 1 kW per 10 m2 of heated area for a standard house with a masonry of 2 bricks and a ceiling height of no more than 2.7 meters.
According to the technology for each room is calculated separately, but in practice often the total area divided by 10 and multiplied by 1 kW. Then add losses and inaccuracies in the calculations to increase the resulting power by 20%, if the planned and the circuit of hot water, you must add another 20% margin.
For example, the standard boiler capacity for heating and DHW when working on an area of 150 m 2 can be: (150×1)/10 = 15 kW for heating. But it is necessary to reserve the power. 15 kW x 0.2 = 3 kW reserve for frost, losses and deviations. 15 kW x 0.2 = 3 kW for DHW. Minimum required boiler capacity in this case must be at least 15 3 3 = 21 kW.
Overdimensioning gives the boiler an under-utilization, but keeps it in a position to expand its use in the future. Mistake in power shortage promises loss of comfort and inevitable redesign of the heating system.
This is largely approximate calculation, you can for the exact calculation to attract heat engineer or yourself based on SNiP 2.04.01-85 recalculate the flow rate of DHW in accordance with the norms, but will still have to take into account the safety margin, and the choice of a particular model such estimates affect little. For a detached house up to 400 m2. the above calculation is sufficient in more than 90% of cases.
How to calculate the required boiler capacity Individual calculation, formula and correction factors
Moving out of the city to the countryside in a private home for permanent residence will inevitably put before a modern man two extremely important problems: a reliable and comfortable heating and enough hot water. It is not uncommon to add another circuit to the heating. floor heating. You can arrange all three circuits: heating, DHW and underfloor heating is completely independent of each other, but the equipment with control and piping can take a significant part of the living space and reduce the reliability of the system, not to mention the higher cost and installation costs.
Two-circuit solid fuel boilers can solve these problems. For those wishing to become independent of expensive gas and reduce electricity consumption, there are many two-circuit solid fuel boilers on the market. Despite the fact that they are more expensive than single-circuit (sometimes the price is higher by 30%), this is the most budget-friendly way to organize the hot water supply. The right choice of boiler will create a simple, reliable, and with the availability of inexpensive fuel, cost-effective system.
Models of greater power, using different types of fuel, as well as different principles of combustion and additional options will cost the buyer and 100 000.
The use of two-circuit solid fuel boilers provides the following features:
- Full independence from gas and electricity networks (in the case of a boiler unit energy-independent or alternative sources of electricity are used);
- real economy at the expense of rather high efficiency and use of accessible inexpensive fuel (wood and its waste, coal, then).
- Ease of maintenance, especially with inexpensive systems without automatic fuel delivery;
- reliability and long-term use with proper installation and operation.
But there are also many disadvantages of systems that use solid fuel boilers:
- The need to stock fuel without getting wet and provide additional meters in the boiler room for loading;
- The need for inexpensive boilers to load fuel manually. Automatic loading, which allows the boiler to work for several days, is a rare and expensive option, reducing the reliability of the system;
- Careful attention to the quality of fuel takes time;
- Regular cleaning of ash, cleaning of carbon deposits and inspection of the chimney.
