A wood-fired boiler is an excellent solution for a modern lifestyle, given the periodic increase in the cost of energy. Some five years ago, few people were interested in how such boilers work, but now more and more people are interested in the possibility of installing such a device at home.
If you do not yet have a boiler for long burning on wood for a home, then you can either upgrade the one that you have, while receiving quite acceptable efficiency, or buy a new model. It will work efficiently and economically and will make it possible to recoup all investments in a short time.
Fuel price
Besides the fact that a wood-fired boiler will help you save your money, it also helps to save the planet’s energy resource. Installation of such an installation helps to take care not only of your family budget, but also of the entire environment.
The price of wood-fired boilers must also be taken into account, based on its further operation, so it is worthwhile to find out the price for fuel. If you are interested in the current cost of fuel for this heating system, then you can familiarize yourself with the numbers:
- Firewood for heating boilers. A cubic meter of firewood costs from 30 to 50 dollars. For the heating season, a small building needs about 12 cubic meters.
- Pellets This is a relatively new type of fuel, but it is very popular. Numerous wood wastes are sent to the press and the resulting raw materials are sold at $ 100 per bag. In the bag is 40 kilograms of pellets. It is worth considering that heating systems for such fuel give an efficiency of 95%, which is very impressive. The use of such fuel will allow you to recoup all expenses in 1.5 years.
- Gas is a very expensive fuel in our time, which costs about $ 8 for the first 200 m 3 . If you exceed the norm, then the tariff for use will almost double. Thus, for a building on 400 square meters for the entire heating season will have to spend about $ 3,000.
- Coal. Its cost varies from 130 to 240 dollars per ton. It all depends on the brand, among which anthracite is the highest price. A small house needs about 2 tons of fuel for the entire heating season.
As you can see, solid fuels are much more financially efficient than electricity or gas. Related to this is the fact that most heating boilers are designed for firewood and coal. Pellets, of course, are considered the most profitable solution, but they are not always available.
The advantages of classic boilers
Before you purchase a boiler for heating a house on wood, you must also understand what its strengths and weaknesses are.
Why not use traditional boilers? Nowadays, modern models of wood-fired boilers practically do not have any competitors, since classical installations that work on the principle of continuous burning, like fireplaces and stoves, have a number of significant drawbacks.
- Low indicator of efficiency.
- High consumption of raw materials.
- Weak energy intensity indicators.
- Short-term heat production.
Also, technical indicators are not particularly impressive, if we compare them with modern installations:
- Power. For classic models - 7-50 kW, long burning - up to 100 kW.
- Working hours. Direct burning - 4-6 hours, lasting from 24 to 144 hours;
- Temperature indicators. Classic installations - 60-70 ° , modern - 70-80 ° .
- Raw materials for heating. Direct burning models only support firewood and coal, and long-burning plants work with all wood waste, as well as coal.
Moreover, boilers of an obsolete type will certainly need constant attention. There it is periodically necessary to add new fuel, remove accumulated ash and other residues. Without careful monitoring of such boilers by the owner, he will quickly begin to fade or, not at all for the better, burn out and fail.
The cheapest fuel for a solid fuel boiler is still considered firewood. If you combine this raw material with a fuel unit, then the owners will certainly get a tangible advantage from this choice. It is also worth noting that the installation of any model of gas boilers, taking into account all the inherent bureaucratic red tape, such as design, preparation of permits, project development and much more, will be equivalent to buying a modern boiler model that runs on solid fuels.
The main advantage that a wood-fired boiler has for a private house is that the cost of each unit of thermal energy received will be significantly less than for any other type of fuel.
How do modern boiler models work?
The structure of the operation of this device is based on restricting the access of oxygen, due to which the fuel decays very slowly, releasing gas. It burns out after allocation, which helps to increase the efficiency of the entire device.
According to their design features, wood-burning boilers for home can be divided into three categories:
- Equipped with an extended firebox. Air enters portionwise immediately into the combustion area. Thus, one load burns out in about 8 hours.
- Top burning. The difference between this model and the classical type lies directly in the installation of the burner - arson is carried out from top to bottom, so that an optimal solution is obtained that ensures a long and uniform burning of the resource. Moreover, with this method of combustion, the fuel inside does not burn out so quickly, which makes it possible to give more heat.
- Pyrolysis models. Such devices are considered the most effective, since they have two working chambers in their structure. The first is the boot bay located at the top. You need to put firewood or other fuel in it, like pellets or briquettes, after which it is set on fire. As soon as the fire becomes uniform, pumps that partially draw out oxygen are automatically started. A smoldering process takes place followed by gas evolution. The smoldering area is separated from the common loading compartment thanks to the air distributor. It allows you to provide the necessary boiler operating time for you. The interval between downloads varies from 8 to 24 hours. The second chamber is the final combustion zone, it is located below. This area of the furnace is responsible for burning the gas that has formed inside, and increasing the overall efficiency. Inside the chamber, gas is supplied by nozzles. To ensure the most effective result, fans are installed here. They evenly blow air. All soot and other heavy residues of raw materials are also burned here. The combustion temperature inside reaches a mark of 1000 ° C.
The smoke resulting from combustion does not harm the environment, because it does not contain any harmful components.
The advantage of this solution
Even if you don’t know how to choose a boiler with long burning wood, you will certainly get a lot of advantages from this solution:
- Excellent performance indicators for each model. On average, it is 90-95%, which is a real record for such devices.
- It is possible to set automatic download. Fuel enters the burner without manual intervention. This feature is certainly indicated in the technical passport.
- Energy efficiency is not more than 650 ° C. This temperature can be achieved through proper operation.
- Safety for the environment. Even carbon monoxide burns inside the firebox.
- If necessary, you can smoothly change the intensity of combustion.
- There is an automatic remote control that can report possible problems in the system. However, such functionality is not present in all wood-fired boilers.
- Adjustable water temperature. Such a solution will be relevant for wood-fired boilers with a water circuit.
- Compact and reasonable system. The whole structure takes up very little living space.
- Ease of use. This also applies to the installation process.
Disadvantages of the solution
Classic and combined wood-fired boilers have several drawbacks that are worth mentioning:
- It is necessary to have a special room where fuel will be stored. Boilers are extremely sensitive to the moisture content of the fuel used.
- If you have chosen a model without automatic fuel loading, then you will have to do your own loading of firewood and other raw materials.
- Some models may not have automatic temperature settings. You can familiarize yourself with the instruction manual in advance; it is supplied with the product.
If you want to put an ordinary or water boiler on wood for a house, then you also need qualified help from a specialist who will help with the right choice of the right model.
Varieties of boilers
There are a large variety of models of solid fuel boilers. They can have their own characteristics and unique functions, which can affect your decision. Moreover, the price of a wood-fired boiler also depends on this.
Cast iron model
Cast iron boilers can be equipped with manual or automatic bookmarking. It is worth noting that manufacturers with automatic bookmarking are increasingly called stations. The presented devices for heating contain an automation unit and controllers in the form of a system of temperature sensors. Fuel in such a system is not only firewood, but also coal. The combustion process runs from top to bottom.
Product Features:
- Material - cast iron.
- The burning time from one bookmark is 24 hours from firewood, 144 hours on coal.
- Fuel: coal, firewood, briquettes, pellets and other wood waste.
- The efficiency indicator is 90%.
- The power of the device starts from 9 kW.
Advantages:
- excellent indicator of efficiency;
- simple operating mode, fuel loading is rarely needed;
- You can choose different fuel options;
- the material has a long life of 50 years; for example, steel can last about 10 years.
Cons of the device:
- heaviness;
- difficult installation, due to the large weight;
- high cost of goods.
The price of wood-fired boilers depends most of all on the product brand. The average price starts at $ 1,200.
Pyrolysis boiler
Such upgraded options are also called gas boiler, equipped with two working chambers. They make it possible to burn not only fuel, but also the gas that is released during combustion. The combustion process lasts until the moment when the temperature does not reach the mark of 200 ° C. Next, the damper is closed by air distributors. After that, only smoldering and burning of gas occurs. The device is highly efficient.
Key device parameters:
- Material - alloy steel, the thickness of which is 8 millimeters.
- Burning time of one bookmark is from 6 to 24 hours.
- Fuel - waste from wood and firewood.
- The efficiency of the device is 95-98%.
- Power indicator - from 50 kW.
Advantages of choice:
- high efficiency;
- ease of use;
- high efficiency indicators;
- no harm to the environment.
Cons of the decision:
- The need for electricity for a wood heating boiler. Oxygen is supplied by fans.
- High price of goods.
- The effectiveness of the device depends on the level of moisture in the fuel (the maximum allowable parameter is 35%).
Cost starts from 1800 dollars.
Long burning boilers
They can be equipped with a top ignition of fuel or provide slow burning due to the elongated model of the furnace. These are universal models that can be used to load a variety of kindling material.
Main qualities:
- Material - metal, steel and cast iron, steady against high temperatures.
- The burning period of one bookmark is from 6 to 12 hours.
- Material for fuel - wood waste and firewood are mainly used, however, there are models designed for coal.
- Efficiency - 90%.
- Power level - from 10 kW.
The advantages of this model:
- easy installation and ease of operation;
- excellent efficiency;
- easy way to download;
- low cost in comparison with other options.
Minus models:
- during combustion, carbon monoxide is emitted into the atmosphere.
The cost varies from 500 to 700 dollars.
How does a dual camera work?
Long burning devices can get the maximum heat from the fuel due to the presence of two working chambers. Inside one of them, the process of fuel combustion occurs, when in the other all the released raw materials from gas and other combustion components, such as ash, are burned.
Combustion waste can be burned in various areas of the device, depending on the model. It can be above, behind or below. Nevertheless, the unconditional classic is precisely the lower combustion.
By the type of fuel used, such boilers are universal. A variety of wood waste, such as pressed wood, peat or coal, can be sent inside the firebox. The main requirement for raw materials can be called dryness. Wet fuel reduces gas production and the efficiency of all heating, because some of the stove’s power will go just to dry the fuel.
Most often, the furnace is loaded to the maximum, as much as the volume allows. Kindle is in progress, doors are closing. The oxygen supply is additionally regulated using a special sensor. After one working cycle, only a small handful of ash will remain at the bottom.
Advantages of indirect heating
Devices that have the function of heating water in a special boiler or heat exchanger are very popular with consumers. After it can be used for various household needs. Such devices are equipped simultaneously with two working circuits that heat the house and heat the water, a heat exchange component and a water jacket.
The system for heating water works according to the scheme of the accumulating boiler or according to the flow pattern. It all depends on the direct installation model. The larger the boiler has volume, the greater will be the supply of warm water for the owners themselves. Thus, two problems can be solved simultaneously - to get a heated house with hot water, as well as significantly save energy costs.
Automatic feed
An important part of such boilers is the installation for automatic fuel loading. This module is available on all pyrolysis boilers that work with pellets or coal. The system practically does not need human intervention. Everything is carried out automatically: raw materials are supplied, kindling takes place, then all ash is removed from the furnace area. Nevertheless, the presence of such automation makes the boiler dependent on electrical power, because you need working fans. Also, its cost is higher than that of devices with manual loading.