Every year, modern autonomous heating systems are becoming more and more popular among owners of suburban real estate. For one reason or another, traditional gas heating units are rejected by the owners of private houses (mainly due to the high cost and unavailability of gas) and they are being replaced by universal combined boilers.

These are surprisingly reliable, functional and efficient devices, thanks to which you can provide heating for your home or any other property.

Combined heating boilers: electricity and wood as the main fuel

Currently, the greatest demand among the combined equipment is used for heating boilers for wood and electricity. A feature of this technique, as you can see from the name, is the simultaneous operation of both solid fuel (wood, woodworking waste) and electricity. This versatility is ensured due to the unique well-thought-out and rather practical design of the equipment.

By and large, wood and electricity heating boilers differ from traditional solid fuel boilers only by the additionally built-in heating element (installed in the heat exchanger tank). It should be noted that also in such heating equipment, an automation system is used, which allows you to change the boiler power, operating modes, and also ensure switching between types of fuel.

Heating technology: accessories and functionality enhancements

A variety of combined heating boilers, gas, firewood and electricity are often equipped with special sensors and other systems, due to which the productivity of equipment is significantly increased. Such sensors allow the equipment to automatically turn on electric heating elements, thereby ensuring the continuity of heating.

Such versatility is especially effective in cases where the power of the equipment in the mode of combustion of wood or other solid fuel is not enough.

Any heating boiler powered by electricity and wood is also good because it perfectly copes with low-power operating modes. The instruction for such a technique assumes that even with irregular operation of the boiler, it will be able to effectively maintain a constant minimum temperature in the room, excluding the possibility of liquid freezing in the heating system.

Design features of boilers

Any heating boiler on wood and electricity has, as a rule, a fairly simple, but at the same time well thought-out design. Often, a firebox is installed at the bottom of the unit, where any solid fuel is loaded, be it firewood, coal or peat.

The heat released during the combustion of the fuel heats up the heat exchanger with the liquid, which subsequently enters the heating system.

Heat source: firewood - electricity in the house

If you switch the heat source to operation on electricity, then the coolant in the system will be heated by heating elements. And even with low-power operation, it is electricity that allows maintaining a constant minimum temperature of the coolant in automatic mode.

Installation and operating conditions of combi boilers

Unlike traditional heating units, boilers using a combination of several types of energy require special installation and maintenance conditions. It is especially important to consider these requirements for the installation process if the work is done by hand.

First, you should point out the fact that for such heating units in a private house, it is imperative to assign a special separate room. Also, it is necessary to provide a concrete cushion for the unit, equip a chimney and a ventilation system. On our website you can see photos and videos of installed boilers in various houses.

Advice. If you are not confident in your own abilities, entrust the performance of all installation work to qualified specialists. Real masters in the shortest possible time will perform the entire range of works, ensuring their high quality and compliance with requirements and standards. In addition, you will have a guarantee for the work performed.

Advantages of solid fuel and electricity boilers

If we compare the combined equipment for heating country houses with traditional gas or simple solid fuel boilers, then their advantages are simply obvious:

• Fuel availability and low price. Due to the possibility of working on solid fuel, it is possible to ensure the incineration of almost any waste of the woodworking industry, the cost of which is just a penny;
• Versatility. Due to the presence of heating elements in the design, heat can be obtained from the boiler even when there is no possibility of using firewood;
• Profitability. Wood and electricity are the most affordable types of fuel in our time, and therefore, you can significantly save on installing a combined boiler and heating a house. Savings are especially relevant in light of the regular rise in gas prices;
• Ecological cleanliness and absence of harmful emissions from the heating system;
• Availability of automation systems and special programmers. Such equipment makes possible the operation of heating equipment in automatic mode in the absence of owners in the house;

• High quality heating. The products of the woodworking industry, like electricity, emit a lot of heat, and therefore the heating of the coolant will be carried out as quickly and efficiently as possible. In addition, there are no significant energy losses, since the combined equipment has a well-thought-out design;
• Duration of trouble-free operation.

Conclusion

Combined heating systems are an excellent choice for any private home. The availability of fuel, reliability, versatility and high performance distinguish the units favorably from the total number of heating boilers on the domestic market.

During the heating season, comfortable living in a country house cannot be imagined without high-quality heating of the home. And therefore, for the owners of private houses located far from cities and regional centers, the question of acquiring a high-quality autonomous boiler is becoming more and more urgent.

In the absence of gas supply and the inexpediency of stretching the gas network to the house, for example, if the gas main is removed or there is none at all in the region, many owners of private households use alternative sources generating heat, for example, using solid fuels or electricity.

Advantages of combined boilers

Using firewood and electricity separately has many disadvantages, which practically disappear if you use a combined firewood-electricity boiler to heat a house.

The advantages of heating boilers on wood and electricity are:

• use in any region of the country, without being tied to a gas pipeline, because access to firewood and electricity is practically unlimited;
• there is no dependence on the supply of electricity, because, when the light is turned off as a result of a wire break or for some other reason, you can always switch to an alternative heating method;
• the use of firewood will save on electricity, since their price in many regions is lower than the cost of electricity;
• the opportunity for the owner to decide for himself about the beginning or end of the heating season;
• there is no need to constantly monitor the presence of firewood in the firebox;
• built-in automation that allows you to set the required temperature and heating power;
• affordable price.

Thanks to the automatic burner switching system, the owner of the house is not tied to a place and can leave the home for a while without worrying that the heating system will defrost. After all, if the solid fuel burns out, but there is no new supply, when the temperature in the heat exchanger drops, the automatics are triggered, switching the operation of the device from wood to electric heating mode... And the boiler starts working only on electricity until solid fuel gets into the furnace. Therefore, freezing of the heating system is completely excluded by maintaining the minimum temperature of the heat exchanger.

Firewood boiler device - electricity

Combined boiler has a fairly simple design and consists of:

• furnaces for loading solid fuel;
• ash chambers, through which air is circulated, which is necessary for the combustion process;
• a heat exchanger in which water is heated;
• grate.

Unlike simple boilers operating only on solid fuels, an electric heating element is built into the heat exchanger of a combined boiler, which maintains the required temperature. In this case, firewood is the main type of fuel. They are loaded into a specially provided firebox, heating the coolant, the heat from which goes to the heating system. Boiler start-up it is recommended to start with firewood, and only after warming up the heat exchanger, transfer to operation from the network. This will reduce energy consumption and heat the room in a short time.

The solid fuel and electrical systems are controlled separately. The heating elements are controlled by an electric unit, and the thermostat, by changing the opening angle of the ash chamber flap, supplies air into it, which maintains the required force of solid fuel combustion.

From both sides, pipes are supplied to the device, at the inlet with cold water, at the outlet with hot water, which, in turn, goes to the radiators or warm floor.

Mixed boiler selection

When choosing a combi boiler for heating, you should pay attention to the following points:

Installation Requirements

When installing a combi boiler, a chimney is a prerequisite, as for a unit with solid fuel. For the flawless operation of the device, one of the main rules for installing the chimney is good draft, for this the height of the required pipe head must be at least 0.5 m.

Combined boilers are produced only in a floor-standing version and should be installed in a separate well-ventilated room - a boiler room. The main room and chimney requirements:

It must be remembered that a combi boiler cannot be installed without permits. Indeed, for him without fail, a dedicated power line designed for 380 volts is required. The unit is connected strictly according to the instructions, because the slightest deviation from its points can cause the device to malfunction... For safe operation of the boiler, it must be grounded. In addition, strict adherence to fire safety is necessary, for this:

• there must be no flammable or flammable materials in the boiler room around the appliance;
• it is necessary to lay a metal sheet in front of the firebox, this will help prevent fire when a burning fuel or spark falls out of the firebox.

Correctly installed, working electric boiler for heating does not harm the environment. But with all the advantages of a mixed boiler, it has there are some disadvantages:

• high cost of electricity;
• the need to prepare firewood for the heating period and store them in a separate room.

Using a combi boiler for heating will help create comfortable warmth and coziness in the house. And in the absence of centralized gas supply, it is the best choice.

Combined solid fuel boiler is considered the most common type of universal equipment. Below we will talk about all types of fuel combinations.

To begin with, we note that universal boilers can have two circuits:

1. One circuit - designed for heating the room.
2. Two circuits - the ability to provide a room with heat and hot water in a flowing mode.

Just like other units, universal boilers are floor-standing and wall-mounted. Unlike a boiler with a steel heat exchanger, equipment equipped with a cast iron heat exchanger has a greater weight, and, accordingly, a floor modification. However, cast iron is a much more durable material and increases the life of the boiler. The average service life of such a device is 30 years, subject to all the necessary rules for tying such equipment.

Universal heating boilers

Undoubtedly, the combi boiler has a lot of positive characteristics. The main advantages are, of course, its versatility and practicality.

Before buying a universal heating boiler for a home, we recommend that you familiarize yourself with all the variations offered to the consumer. By the number of burners used, such boilers are divided into:

1. Multi-fuel - is used from three types of fuel.
2. Bi-fuel - it is possible to use two types of fuel.

Prices for universal boilers for heating a private house are higher than for conventional boilers that run on one type of fuel. Nevertheless, such equipment is a great opportunity to use all available resources.

The owners of universal equipment claim that buying a double-circuit combined boiler for heating a private house was the right decision, since such a device is very economical and efficient.

Gas fired boilers with combi fuels

The versatile equipment has many fuel combinations.

Multi-fuel:

1. Are used:

• firewood
• electricity

1. Are used:

• firewood coal pellets
• electricity

Bi-fuel:

• gas electricity
• gas diesel
• gas firewood coal pellets

Coal gas heating boilers are very popular.

Wood and electricity boilers

An electric wood-fired heating boiler is ideal for rooms that are not connected to the main gas. Basically, such equipment can operate on different types of fuel. For a combined heating boiler, firewood and electricity, the price, as well as for other similar units, depends on the capacity of the equipment. Other technical characteristics of the equipment also affect the pricing. A universal boiler, working according to the firewood electricity scheme, is easy to operate. Typically, the design of such a boiler is as follows: a solid fuel steel boiler is combined with an electric heating element of various capacities. It can be either natively built-in or built-in if necessary. Electricity is used to maintain the temperature of the coolant after the firewood burns out. The standard electric heating element is selected based on the power of the solid fuel boiler in a ratio of 1: 2. Equipment that uses solid fuel, wood, coal, electricity, is considered highly efficient and economical. A solid fuel boiler with an electric heating element is the most profitable combined heating equipment. Like any other solid fuel unit, such boilers require a stainless steel chimney with thermal insulation and the presence of compulsory supply ventilation in the room where it is installed.

Heating boilers combined with solid and diesel fuel

The boiler for liquid and solid fuels can operate on diesel and wood (coal, pellets). Various modifications of such boilers are presented in the range. It is advisable to install a universal boiler for wood and diesel fuel in a separate room. It is recommended to entrust the installation to specialists. The combination of two types of fuel (diesel and wood) is the most cost-effective for the consumer.

Combined solid fuel boilers

Solid fuels can be combined in different variations:

• wood pellets;
• wood chips pellets;
• coal pellets;

Be sure to read the instructions supplied with the equipment. The manufacturer indicates which type of fuel can be used in the operation of this particular boiler.

Combined boilers: main advantages

Gas is the optimal energy carrier for a heat generator in a private house, it is environmentally friendly and inexpensive. Heating devices operating on such fuel do not require constant maintenance (like, for example, solid fuel boilers). But the fact is that for work, a gas pressure of 3.5 mbar is necessary, and it can be unstable.

Combined heating boilers for a private house can reduce the risk of interruptions in the supply of energy, and when these interruptions occur, the device automatically switches to an alternative fuel. Thanks to this mechanism, home owners do not have to switch the device on their own - such a boiler will not freeze under any conditions.

The autonomous operation of these devices is not without certain disadvantages:

• they are quite heavy and cumbersome, therefore they are produced only in floor-standing versions;
• their installation requires a separate room;
• complex design of devices, predetermined problems with repair and service.

Types of combined boilers

Combined boilers are classified according to the combination of the type of energy carrier used. Such devices can use all existing types of coolant:

• electricity;
• solid fuel;
• liquid fuel;
• natural gas.

Some models of heat generators can use only two types of fuel, for example, electricity-wood or gas-electricity, and the most "advanced" models can work with all types of energy carriers. When you consider models of combined heating devices in a store, it is not immediately clear what type of energy carrier is used in it. This issue will be clarified by the special marking present on all combined boilers.

For example, the “TG” label indicates that the device can operate on gas and solid fuel, and the “TE” label indicates that the boiler runs on electricity and solid fuel. The most advanced units are marked "TGE". The design of these devices includes a gas and liquid fuel burner, a solid fuel furnace and electric heating elements. Therefore, such devices are able to provide complete autonomy.

Quite popular among summer residents, whose dwellings are located in villages with a gas pipeline, a combined gas boiler, firewood. This is justified by the fact that in many summer cottages, gas is supplied, but pressure and supply failures are possible, as mentioned earlier. Also, such units are used in remote private houses where gas tanks are installed. If the gas supply is abruptly interrupted, the alternative would be to switch to another energy source - solid fuel.

The most popular among consumers are heating boilers, combined firewood, electricity. This popularity is due to the relatively low cost compared to TGE models and the availability of the energy carrier. Electricity, unlike gas, is available even in the most remote places, and it is not difficult to stock up on firewood.

Advantages

In such boilers, solid fuel acts as the main one, and electricity only serves to maintain a comfortable temperature in the house. Modern models can carry out the transition automatically by time or upon reaching a certain temperature in the room. It is especially convenient to use electricity at night, when during sleep the owner cannot personally control the process of burning firewood.

The most important advantage of the unit is the use of a two-tariff electricity meter at night. The ideal economical system is precisely heating at night, and during the day, only maintaining the temperature with wood and using them in case of problems with the main energy source.

How to choose a boiler firewood electricity

Combined boiler firewood electricity can be single or double-circuit. In the first case, the unit only heats the room, and in the second, it also heats the water for domestic needs. If you decide to opt for this type of combined boilers, then when buying a heat generator of this type, you should pay attention to the following nuances:

• volume of the firebox;
• the possibility of silent work;
• heat generator power;
• unit weight;
• grate material;
• heat exchanger material.

The last two points should be clarified in more detail, since the efficiency and service life of the combi boiler depend on them. The grates can be made of cast iron or ceramics. Cast iron is preferable when firewood is used as solid fuel, they are more heat-resistant. Ceramic grates are more suitable when it is planned to use bulk fuel - pellets, straw, sawdust.

Heat exchanger material

The heat exchanger can be made of carbon steel, cast iron or stainless steel. The first option tolerates temperature changes well, but is susceptible to corrosion. However, this drawback can be eliminated if not water is used as a heat carrier, but an anti-freeze liquid.

Heat carriers made of stainless steel and cast iron are not subject to corrosion, but cast iron does not tolerate sudden temperature changes and mechanical damage, and a stainless steel heat exchanger has half the service life.

What to look for when choosing a combined boiler for heating a private house

Before choosing a combi boiler, there are many factors to consider:

• single or double-circuit - according to the configuration of the heating system of a private house;
• power - calculate by the size of the dwelling and its thermal insulation;
• take into account the economic component;
• the fuel used according to the availability of a particular type of energy carrier, both primary and secondary;
• the presence of a chimney, depending on the structural characteristics of the building.

And these are far from all the nuances that determine the model of the combined boiler. By contacting professional consultants, you can avoid unnecessary expenses, choose the right model and ensure warmth and comfort in your home at any time of the year.

Outcome

Combined boilers can be a real salvation in the case when it is not possible to use a reliable and constant source of energy. In addition, such boilers can help save money by using a more expensive type of fuel only as an auxiliary option.

Until recently, the owners of private houses did not even think about what kind of fuel the heat source would operate on to heat their homes. The question was considered rhetorical, and the answer was clear - it is natural gas. However, the time has come for non-standard solutions, since energy resources are constantly becoming more expensive, and it is not known which of them will be beneficial for use tomorrow. That is why there has been a massive interest in heating installations such as an electric wood-fired boiler.

Why are combined units so good?

The solution is really non-standard, and it makes it possible to kill several birds with one stone:

• find an alternative to natural gas for heating;
• to play it safe for the future, having in reserve as many as two additional energy carriers;
• at the same time ensure comfortable operation of the heater, eliminating the need to fiddle with firewood in the furnace at night.

It is also important to organize heating with electric wood-burning boilers in new buildings, for the same reasons. At the same time, it is possible to recall the old-fashioned methods and install a gravity heating system in order to maximize independence from external influences. Although the convection system is not the best solution in terms of efficiency, it is affordable for installation. And in the event of a power outage, you can always safely switch to firewood.

Unit design features

Externally, the device of an electric-wood boiler practically does not differ from a traditional solid fuel heat generator. Only in one place, where the unit's water jacket is located under the casing and thermal insulation, is there a special hole from which the contacts for connecting electrical wires are visible. In reality, the combi plant has a combustion chamber for loading solid fuels, an ash chamber with a damper through which combustion air passes, and a grate.

Domestic combined boilers for wood and electricity can be equipped with both a water-tube heat exchanger and smoke tubes. Some models are also equipped with hobs located in the upper part of the combustion chamber. That is, these are full-fledged solid fuel plants with an efficiency of 75-85%. But they have one design feature: one of the walls of the firebox, which is the inner lining of the water jacket, has a complex profile, made using cold stamping. Thanks to this profile, one or more heating elements are placed in the space between the inner and outer skin of the shirt. This is a special case of the scheme according to which electric-wood heating boilers are made, heating elements can be built into the boiler tank in other ways.

When, for any reason, the boiler cannot operate on the main fuel - wood, it automatically switches to electricity and vice versa, when the furnace is ignited, the electric heaters are turned off.

Boiler operation description

The heating elements are controlled by the electric unit, and the intensity of solid fuel combustion is regulated by the air supply thermostat, opening the ash chamber flap with a chain at a certain angle. That is, the control functions of the electric and solid fuel parts of the heater are separate. If the air is supplied to the furnace forcibly by a fan, then both parts are controlled by the automatics for the wood-burning boiler. In the first case, the operation algorithm is as follows:

After connecting the heat generator to the network, the electric heater turns on. The temperature of the coolant is set on the control panel and the heating element begins to heat the water in automatic mode. It is better to set the temperature 10-15 ºС below the working temperature.

At this time, fuel is loaded into the combustion chamber and ignited. From this moment, the heating of the coolant occurs jointly, if the electric heaters are not forcibly turned off.

Having reached the water temperature set on the control panel, the heating elements are turned off and the coolant is heated with wood until the operating temperature. The intensity of combustion is controlled by a chain-driven thermostat, and as soon as the water reaches the operating temperature, it shuts off the air supply.

When the combi boiler burns its main fuel and there is no new load, the coolant will start to cool down and at a certain moment the sensor of the electric unit will work and it will turn on the heaters that will maintain the water temperature until the next firewood is loaded.

The algorithm for working with an air supply fan and a single electronic unit is similar to that described above, only the process of setting up the equipment is simplified. In this case, the non-volatility of the solid fuel part of the unit is lost.

Due to their design and principle of operation, electric-wood heating boilers for a private house acquire some advantages that are unusual for conventional solid fuel units:

1. Condensation does not form on the inner walls of the furnace due to the flow of cold water from the return pipeline, since the boiler tank is constantly heated by the heating element.
2. As a result, the building heating system can be connected directly to the heat source, without the organization of a small circuit and a mixing unit with a three-way valve.
3. Theoretically, the efficiency of the combined water heater rises to 97-99% while the electric heating is in effect and the main firebox is not functioning.

At the same time, the versatility of the unit does not eliminate the disadvantages inherent in both types of heaters separately. This is inertia, which is expressed in the inability to immediately stop heating the coolant when the maximum temperature is reached.

Another drawback is the relatively low power of the electrical part, it will not be significantly increased by the device of a water jacket, it is impossible to build many electric heaters into it. For this reason, the power of the electric heaters is equal to the power of the wood-burning combustion chamber in the range of 6-25 kW. If a higher indicator is required, then the electricity will serve only as heating and will be able to maintain the temperature of the coolant at a certain level.

Conclusion

The use of universal installations electricity - solid fuel for heating a small private house is a fairly rational solution that gives a lot of advantages over a separate system. Yes, and the question of cost plays a role; at the price of a combined heater, it will not be possible to buy separately solid fuel and electric heating boilers.