The issue of heating in the winter season is acute for everyone who plans to build their own country house. Electrical equipment is too expensive for most consumers, and connecting to a gas supply network is far from affordable. In this case, the alternative will be the well-known wood-burning stoves, which for many centuries have not lost their relevance.
Varieties
Depending on the needs, consumers can choose stove equipment with a water circuit of various capacities. There are stoves equipped with a tank for storing wood pellets, as well as an automatic pellet feeder. It is a screw conveyor or pneumatic device.
Modern wood-burning stoves are equipped with a control system that allows you to set the optimal mode of operation, providing a specific temperature for a certain period of time. With a small load, loading fuel and cleaning ash should not be done often.
If a large volume of water is required for various domestic needs, it is recommended to purchase units in which 10% of the heat is spent on heating needs and 90% is spent on water heating, which will subsequently be sent to the heating system or to the storage.
Distinguish furnaces with a water circuit, which are equipped with a forced ventilation system, programming automation and a remote control.
Such equipment can be called universal heating devices, combining simultaneously the functions of titanium and boiler. Thanks to this, water heating from a wood-burning stove is an ideal option for country houses, cottages and cottages.
Design
A classic oven consists of the following basic elements:
- chimney flue;
- boilers through which combustion products and smoke rise up;
- the firebox in which the combustion of firewood occurs;
- ash pan for efficient cleaning of the furnace from ash.
In the process of operation of the furnace unit, all four walls of the structure are heated. As a heat source, you can use briquettes or firewood. The main material for the construction of the furnace is red brick.
Principle of operation
Units with a water circuit are equipped with a heat exchanger integrated in the furnace or chimney duct. There are models that can function in steam circulation mode.
The wood-burning stove can be made of boiler steel, cast iron, designed to operate under high steam pressure. These devices are used both as additional equipment and as the main source of heat.
A heat exchanger is installed inside the furnace unit. The channels of the heating tank move heated gases that transfer heat to the liquid. A furnace with a boiler in its design can have several tanks at the same time, which can significantly increase its efficiency. Water is heated in one tank, with enhanced heating in the second there is a process of vaporization.
To heat a large building with traditional stove heating, several stoves will be required, while the consumption of coal or fuel will be quite high. Therefore, a more economical and alternative option would be a stove for water heating of a wood-burning house, equipped with a special hot-water boiler mounted in the furnace. Even in severe frosts, a two-time kindling of the furnace is enough for such a heating system.
Such devices are able to heat the building even in between fireboxes. In the process of cooling, the pipelines give off their heat for another 5-6 hours, thereby they carry out heating without fuel consumption. Water heating from a wood burning stove has an efficiency of 80-85%.
Heat dissipation
For example, take a furnace with an iron boiler 35 cm high, 48 wide, 75 cm long and a water circuit measuring 1020 x 1020 mm. In this case, the efficiency of the furnace unit, subject to proper operation, can reach about 85%. With a two-time furnace, the heat transfer of the furnace will be 6500 kcal / h (7600 W), and the heat transfer of the boiler will be 15 000 kcal / h (17 500 W).
If you calculate the total heat transfer of a wood-burning stove with a water tank and boiler, you get about 21,500 kcal / h (25,000 W). Using this heating option in severe frosts will allow heating a room of up to 300 m 2 .
The large heat transfer of the furnace unit is achieved by heating the surface of the water boiler. The body of the metal tank is washed from all sides by hot gases. At the same time, the inner surface of the heating chamber also heats up well, which makes it possible to maintain a heated water boiler in a break between fireboxes (about 7-8 hours).
Thus, compared with conventional solid fuel boilers, water heating from a wood burning stove is much cheaper.
Advantages and disadvantages
Despite the appearance of an incredible number of technical innovations intended for heating rooms, owners of private houses prefer stove equipment. And there are many significant reasons.
Benefits
- Profitability. The services of a stove-maker will be much cheaper than the purchase of modern devices, their maintenance and installation. The stove can be folded from mortar and brick, which remained after the construction of the house. Repair and operation of such devices does not require large investments.
- Variability of design. A modern craftsman can fold an oven of any shape and size. It can be decorated with exquisite designer decor, painted in various colors. There are designs that combine a fireplace and stove.
- High degree of maintainability. Over the years of operation, this equipment requires only minor cosmetic repairs. This is much faster, cheaper and easier than taking an expensive unit to service.
- Possibility of regulation of combustion intensity in the furnace.
- The atmosphere of comfort, which is characteristic only of Russian ancient huts with stoves.
- The intensity and speed of heating the air is determined by the position of the dampers.
disadvantages
- For water heating from a wood burning stove to generate enough heat, it will take some time. Brickwork warms up for a long time.
- The presence of dry firewood and open fire are high fire hazard factors. When burning fuel, you will not have to leave your home and monitor the stove.
- Ash, soot, sawdust from firewood, dust. In the room where the furnace is located, you will have to clean up more often.
- The uneven distribution of heat in the living space reduces the level of comfort.
- Large overall dimensions of the structure reduce the useful area of the building. By its definition, a furnace cannot be small, since efficiency depends on its size.
Project development
As mentioned above, water heating from a brick stove on wood is a rather dangerous design. Therefore, the development of project documentation is recommended to be entrusted to a specialist who will take into account all the subtleties.
Design Features
- Wood burning stoves, water heating in general, it is desirable to design even before the start of construction in order to consider the optimal layout of the living space. Equipment should be located closer to the center to ensure free access to the firebox. It is not necessary to place the front of the stove in the room, it is preferable to move it into the interior corridor or hallway.
- In the case of close proximity of the unit and interior partitions, it is necessary to provide a ventilated indent or an air gap between them to prevent overheating of wooden structures. For greater safety, the furnace can be lined with fireproof materials or lay partitions with bricks. This will reduce the fire hazard of the heating system.
Water heating from a wood-burning stove: diagram
First of all, it is necessary to determine the functionality of the future furnace unit. Will it be used only for heating water or for other purposes. As a rule, a brick furnace for water heating is carried out in conjunction with the hob, which is relevant for country houses.
Additionally, a complex chimney system should be implemented. In the process of passing through them of hot carbon monoxide, the walls will heat up, and heat will enter the room. They can occupy about 70% of the volume of the furnace, which is not always possible for small houses.
The main component of water heating from the furnace is the heat exchanger. This element transfers heat energy from the combustion of fuel (coal, firewood) to the coolant. The heat exchanger is located at the rear of the combustion chamber.
Choosing the most suitable scheme, you can begin construction. The best option would be to purchase a finished steel model, which can subsequently be coated with protective refractory brick in 1 layer. However, if you need a large powerful unit, it is recommended to do it yourself.
DIY oven
The construction of the furnace begins with the foundation. It is important that it is not tied to the foundation of the house. To do this, a concrete screed is poured into the ground, its height should not exceed the floor level by more than 5–7 cm. Only after this, you can proceed with the construction of the structure.
- The first rows of the ash pan are stacked in accordance with the selected scheme.
- Next, the blower door is mounted and the structure is bricked. The door should be made of cast iron, measuring 19.5 x 24 cm.
- In a similar way, a combustion chamber is performed.
- It is preferable to install a finished chimney of circular cross section.
For an ashpit and a combustion chamber, it is advisable to use fireclay chamotte brick. For cladding, you can choose a regular silicate brick, since it is characterized by good heat capacity.