The problem of heating is one of the most difficult tasks that owners of country houses have to solve. It is impossible to ignore the organization of the heating system - it is impossible to live in an unheated room in winter. Sudden changes in temperature will quickly render the entire finish unusable. Also significantly reduces the service life of the building.
The optimal solution to heating issues is the organization of a water heating heating system, where coolant will circulate through pipes and radiators. The main problem is to choose a heat generator or a boiler that converts external energy sources into heat. Based on the climate, as well as the degree of accessibility of energy resources, long-term combustion units, in particular solid fuel boilers, are gaining more and more popularity today. What is it, consider below.
What is a good long-burning boiler?
Traditionally, gas boilers are installed in private homes. However, not all places have highways with such fuel. In addition, connecting an individual gas line with a gas trunk will require serious costs.
If you add to these costs the mandatory approval procedures, drafting projects in which all the requirements are fully met, the installation process of such a boiler will only scare away the owners. Especially if there are decent alternative solutions.
It would seem that if it is not possible to install a gas boiler, then you can always purchase an electric one. The choice of such equipment is quite large. The boilers have high efficiency, they are easy to adjust, the number of control systems, and also equipped with an automatic control system. However, all these advantages become disadvantages when owners begin to recall the cost of electricity. An ordinary family will easily go broke on such heating.
In addition, in villages that are remote from regional and city centers, the voltage is not very high-quality - you can observe strong changes in the network. And the owner of the
electric boiler makes itself dependent on the quality and stability of the current supply.
Against the background of constant technological progress, the traditional method of heating houses with firewood and other solid fuels has faded into obscurity. But firewood is a good source of energy, moreover, renewable. There is no shortage of wood for heating now. You can use firewood that house owners harvest on their own, or purchase them. Also, many woodworking enterprises sell production waste.
But not all homes have a stove. Yes, it is efficient and retains heat well due to its design. It is good enough to flood the stove to provide the house with heat for a day. But there is one caveat: what to do with the circulation of the coolant along the contours of the heating system? After all, if you just keep burning in the furnace, it will be a big fuel consumption. This problem can be solved with the help of solid fuel boilers of the upper combustion.
Due to the special design of this device, based on the physicochemical properties of the types of solid fuels, it is possible to load firewood once for 12-15 hours. Some models may work more on a single boot.
The advantage of long burning boilers with top burning is also that, in addition to firewood, a number of other materials can be used. Everything that burns is used - it can be briquettes from waste from woodworking industries, as well as coal or peat. Also now, as a source of energy, the so-called euro-woods have become especially popular.
Operating principle
How conventional solid fuel furnaces work is well known to everyone. Fuel is put into the furnace - briquettes or coal. From the lower chamber, an air stream is supplied, which is necessary for the process. The level of combustion in this case is limited only by the amount of oxygen.
This is an ordinary bonfire, which is enclosed in a metal case, requiring constant addition of fuel. The combustion products are directly discharged into the chimney - this system has many turns and labyrinths. This improves heat transfer and leads to an increase in efficiency. However, this does not increase the overall energy return. Thermal decomposition of wood is a quick process, after which a lot of waste remains, and unused energy is released into the atmosphere.
This energy is obtained due to the special characteristics of the tree, which, in turn, are determined by the biochemical composition. When the wood is heated, it not only oxidizes to coal, but also emit carbon dioxide and carbon monoxide. Exposure to high temperatures always leads to the synthesis of volatile hydrocarbon-based compounds. These compounds have a rather complex chemical formula. Gases per se are an excellent fuel, which goes nowhere in an ordinary stove.
Pyrolysis
The process when wood decomposes into gases is called pyrolysis. Combustion temperatures, as well as heat dissipation, are significantly higher than with conventional combustion. Moreover, the oxidative processes of wood are so deep that practically no waste remains after pyrolysis. Only steam and carbon dioxide escape into the atmosphere.
Hence, it is much more rational to use wood fuel, while minimizing the process of open combustion. It is necessary to achieve the release of gases, which are a source of heat. Based on these principles, top burning boilers and pyrolysis units work. We’ll talk about them later.
Types of long-burning boilers
There are two types of solid fuel wood burning units:
- Pyrolysis.
- Top boot systems.
Both options make it possible to get a high-quality autonomous heating system.
Overhead boilers: features
In ordinary boilers, as well as in stoves and fireplaces, fuel burns from the bottom up. This can be explained by the physical processes during combustion. This scheme is ineffective. This disadvantage is completely eliminated in such units. What is the peculiarity of a long-burning top-burning boiler? It is a way of converting energy. So, fuel does not burn down, but on top. Air is also supplied from above and directly to the combustion zone, and not from below through special grates. These are non-volatile sources of heat - and this is a plus of such systems. But they differ in the cyclical nature of the work. Until the bookmark burns, you cannot add another.
The combustion chamber of such boilers is quite roomy. The fuel does not burn below - it waits until the turn reaches it. As the upper layer burns, the lower layer is also involved. Air is supplied from above through special channels or diffusers. These channels are hot from below. Air from the top of the combustion chamber gradually flows down. Due to heating, it will react faster with solid fuel. Thanks to this, high efficiency of the upper combustion boilers is ensured.
The air distributor in the combustion chamber can move - it is able to rise when the fuel is laid. When the combustion process begins, it relies on fuel. So oxygen will only get into the combustion zone. Only smoldering occurs there, and the products of combustion fall exclusively in the upper part. There they are separated by a massive metal disk. Then air is added to these gases, and the products are burned. And the generated heat will go to the heat exchanger.
Often these systems are cylindrical. However, there are also rectangular models. The combustion chamber, as already mentioned, is quite roomy, due to which the maximum duration of the combustion process is achieved. The cylindrical shape makes the device compact and makes it possible to save space.
Benefits
Boilers with upper combustion of fuel are quite durable and reliable. Due to the gradual distribution of the load in the combustion zone in a top-down direction, the boiler body does not heat up to more than 400 degrees. Due to the simpler design, such systems are safer than gas or electric.
Often, such units are designed for different types of solid fuel. This can be firewood, coal, peat, various combustible mixtures, granules, wood waste. The combustion process can last up to 5 days, depending on the design. If you use firewood, then one load of the top burning boiler may last for a period of 8 to 30 hours.
disadvantages
The disadvantages of this equipment include the exactingness and finicky of fuel quality. If you make the unit work on raw wood, then its efficiency will significantly decrease.
The optimum level of
fuel moisture
for solid fuel boilers for long burning with top burning is 13-20%. If you use a more raw product, the boiler will produce significantly less heat. In addition, in this situation, the device may even go out. In addition, if you burn raw firewood in the boiler, a lot of soot and ash will be released. It is necessary to periodically clean both the stove and the chimney. The disadvantages include the need for manual loading.
Pyrolysis
A slightly different principle is used here. The mechanism is based on the breakdown of fuel into pyrolysis gas and coke. This problem is solved due to the low intensity of combustion. Fuel does not burn, but smolders. The result is a gas that burns, combining with oxygen.
Why are there no wall ones?
The long-burning top-loading boiler is only floor standing. Its weight is too large for wall mounting. But structurally - this is the most common solid fuel boiler.
Power depends on destination. Equipment can not only heat rooms, but also heat water. In this case, the heat exchanger can be flow-through or used as a storage tank. The heat exchanger can be either steel or cast iron.
Cast iron boiler is less susceptible to corrosion. This is a very important feature. Condensation appears on the walls of the chamber, and this is a fairly aggressive environment. Cast iron boilers are made in sections. This makes the transportation process much easier.
And if on your own?
It is quite possible to make a top burning boiler with your own hands, and from improvised means. To do this, you need a two-liter barrel, pipe and channel. So, in the barrel the upper part is cut out, and the edges are leveled. A hole is made from above. A pipe is inserted into it, which goes up. It makes a damper to regulate the air supply. The most difficult stage is regulation. The pipe should not be too low, otherwise the combustion process will be fast. If you equip such a structure with a special load, due to which the fuel will settle slowly, as well as a movable air distribution system, you can get a fairly effective system. One bookmark will burn out in 20 hours.
Conclusion
Solid fuel fired boilers are a great and economical way to provide home warmth. The price of such heat will be very affordable. The cost of a new unit of this type starts from 50 thousand rubles, which is quite acceptable.