Heating a private house with a solid fuel wood boiler

The cost of gas and electricity is increasing, and it is impossible to save on heat in the Russian climate. An alternative option is heating with wood or wood waste. In addition, there are settlements where heating with a wood-burning stove is the only possible option. But old-fashioned stoves are a thing of the past. To provide heat to be economical and safe, it is important to choose and install a modern wood-fired boiler correctly.

Device and principle of operation

Each heating boiler must have a combustion chamber, a heat exchange element, an ash pan and a chimney. The simplest apparatus is an oven equipped with a water tank. It is heated by wood combustion and sent to the heating circuit.

Heating equipment works as follows:

1. Firewood is loaded into the combustion chamber, where it burns and gives off heat to the heat exchanger.
2. Pipes are connected to the heat exchange device, the purpose of which is to supply hot water to the general heating system. It is equipped with batteries, an expansion tank and pipes. In addition to heating the liquid, the unit heats the room where it is installed.
3. When wood burns, smoke appears, which is discharged through a chimney to the street. At the same time, soot settles on the walls. A significant amount of it in the chimney leads to a decrease in draft and an increase in the risk of fire.
4. The supply of cold water and the removal of hot water from the heat exchange element is carried out using branch pipes. Automatic systems are installed on the devices of the new generation, which simplify as much as possible the maintenance of boilers for a house on wood.

Chimney cleaning is carried out using special openings called closed dampers. For this purpose, brushes and ruffs are used. You can also add a composition to the firewood, which cleans the chimney from the inside during combustion.

Advantages and disadvantages

Modern boilers for heating with wood for the home are distinguished by an increased efficiency - about 80 percent. In addition, modern units have many other advantages:

• for installation, it is not required to obtain permission from gas workers and firefighters, as well as notify neighbors;
• there are modifications that are adapted to work not only on wood, but also on pellets, coal;
• often devices are equipped with hobs for cooking or heating food;
• combined devices allow not only to heat the home, but also to heat the water.

The most important advantages are independence from electricity and economy. The cost of firewood is about half that of natural gas. Heating with electric appliances is even more expensive in comparison with gas heating.

Wood-burning units also have their drawbacks. In cheap boilers, you have to add fuel every 2-4 hours. In addition to the boiler room, a place is required where firewood will be stored.

The performance of wood-fired boilers is influenced by the type and quality of the fuel. If only wood heating is provided, it is not allowed to use peat briquettes and coal. It is also not allowed to use insufficiently dry wood - when burning, they emit a lot of steam and soot.

Varieties of wood-fired boilers

Solid fuel devices are divided according to the type of combustion. For simple boilers, the efficiency is not too high, and the fuel consumption is significant.The operation of modern devices is based on the principle of long burning. It involves limiting the access of oxygen during the combustion of wood. In fact, the wood smolders rather than burns, while generating more heat. It is possible to regulate the allocated power. The peculiarity is that one batch of fuel is enough for 20-22 hours on average, the time depends on the size of the combustion chamber.

Pyrolysis models are also classified as continuous burning equipment. Their difference lies in the separation of the fuel into a solid residue and pyrolysis gas, which accumulates in the chamber adjacent to the firebox. Due to this, the efficiency is increased to 85 percent, and the ash volume is reduced to 7-15 percent. Gas generating boilers have only one drawback - they require chamber drying fuel, otherwise the unit will not work in normal mode.

Domestic boilers are also subdivided according to the number of circuits that heat water. They are single-circuit and double-circuit.

The first type is intended only for space heating. The second is also used for hot water supply. For this, two coils are installed in the combustion compartment.

Single-circuit boilers can also be used to provide residents with hot water. For this, indirect heating water heaters are connected to them. But at the same time there is a minus - the need to purchase additional equipment.

Criterias of choice

When choosing a boiler, it is worth considering the following indicators:

• Heated area. Approximate efficiency calculations are performed according to the formula 1 kW = 10 sq. M. For example, in the central part of Russia, to heat a house with an area of ​​150 square meters, a device with a capacity of 15 kW is required. For colder regions, a more powerful unit is needed. To heat a similar house in Siberia, it is worth taking a device with a capacity of 30 percent more. When connecting a second DHW circuit, add another 15–20 percent to the total value.
• Material. Cast iron equipment can last 35 years, it has the best thermal and technical performance. But such units are unstable to mechanical damage and weigh a lot. Steel devices are cheaper, they are not afraid of shocks, but their service life is on average 10-15 years shorter.
• Firewood loading type. More often, devices are made in which a side supply of fuel is provided. But there are also top-loading models. A similar design is used in gas-fired boilers. The main advantage of the solution is the possibility of pre-drying the wood, which increases the heating efficiency.
• The ratio of the volume of the combustion chamber and the output of the boiler - how many times during the day it is necessary to load fuel. For devices made of steel, this value is on average 1.5-2.5 l / kW versus 1.1-1.4 l / kW for cast iron.
• Burn protection. An important characteristic, especially with open access to the boiler room. This is achieved by insulating the handles of the combustion chamber and other highly heating elements that protect the cases and grates.
• Additional functionality - automatic sensors, built-in storage boiler, remote control system. All this makes the operation of the heater more convenient. But for some options, it is necessary to connect to an electrical power source, which deprives the unit of autonomy.

In addition to technical indicators, you will need to decide on the brand of the wood boiler and the cost. One of the modifications of the Kupper boiler will be a good option in terms of price and functionality. Their advantage is also in their compactness, which will allow placing the device in a small area.

Installation features

A wood-fired heating boiler can be installed anywhere if it meets technological and fire standards.A technical room with ceilings above 2.2 m and an area of ​​8–12 sq.m is suitable for the boiler room. Supply and exhaust ventilation must be installed, light supplied. Only non-combustible materials are suitable for interior decoration. It is possible to mount the boiler in the basement, provided that it is dry.

When installing, you also need to consider:

• The wood-fired boiler is mounted on a solid foundation. When connecting a cast iron device, you will need to build a concrete base.
• To prevent accidental ignition during fuel loading, a wooden base in the direction of opening the firebox door is covered with a sheet of metal or asbestos cement.
• The installation of the unit is carried out in a place where it will be convenient to service it. All elements must be freely available.
• Firewood should be stored in an adjacent room.
• The chimney is installed following the fire safety requirements during installation. All parts that heat up and pass through the floor slabs and the roof are insulated. A spark arrester is installed at the outlet of the chimney.

If the design of the unit requires connection to the electrical network, a voltage stabilizer and an uninterruptible power supply are used. Automation is connected from the panel by means of circuit breakers and RCDs. In general, the installation is not difficult, it is quite possible to do it yourself.

Rules for the operation of wood-burning boilers

In the process of using a wood-burning boiler to heat a private house, observe the following precautions:

• do not leave the operating equipment for a long time unattended to avoid overheating;
• when working with the firebox, do not forget to wear gloves that protect against burns;
• keep children away from the boiler.

It is important to store firewood no closer than a meter from the firebox, but better in a specially equipped room.

For the efficient operation of a wood-burning heater, it is necessary to constantly procure large quantities of fuel, store it in low humidity conditions. However, you can be sure that the house will be warm even if there is an interruption in the supply of electricity or gas.