Combined boilers for heating a house: types, description of the principle of operation + selection tips

Combined boilers are often used to heat private homes or country cottages for heating a house - they will ensure a comfortable temperature in all rooms, regardless of the presence or absence of a centralized gas supply or firewood.

A significant plus of such units is the adjustment of cost estimates not only for heating the building, but also for the supply of hot water. In addition, it is very convenient to be able to use different types of fuel, agree?

The effectiveness of combined boilers in the absence of access to the central supply system of energy resources is confirmed by numerous reviews of their owners. The main task is to choose the optimal type of heating unit.

We will help you make the right choice. The article describes the features of the operation, operation and maintenance of different types of combined boilers. We identified the main criteria for evaluating equipment and gave practical recommendations for choosing a heating unit.

The main types of combined boilers

Combined heating equipment is focused on loading and processing of two or more types of fuel materials.

More than 70% of the models on the market are equipped with special electric heaters that contribute to the partial or complete refusal to use the main heating elements to heat water in the summer season.

The type of fuel material used allows you to conditionally divide the equipment into 2 main groups:

• standard - apply no more than two different types of fuel;
• universal - able to work on three or more fuel options.

In most cases, it is possible to replace the burner in order to change the fuel supply function. Also available are models equipped with hobs and even two burners with electronic or electromechanical type of control.

The catch here is one - the more extended the functionality of such an aggregate, the more complicated the process of its installation will be.

Pellet boiler refers to solid fuel plants. It burns pellet pellets made from wood waste (+)

Owners of country houses in which heating is provided by a combined heating boiler unanimously declares its indisputable advantage. Especially if the house is located far from large settlements, and the lack of gas supply and frequent power outages are the norm in this area.

In addition, the combined boiler, which is also called universal, has many other advantages.

They allow you to compete with the most popular types of single-component systems:

• the ability to connect multiple circuits;
• a wide range of resources for technical modernization - burner replacement, boiler installation;
• modern level of program management;
• no interruptions in the heating system - at the time of the cessation of the supply of one of the types of fuel there is the opportunity to apply an alternative
• economical consumption of funds for providing a heating system.

Models with electromechanical control will become simply indispensable in homes located in areas that are often faced with power outages.

This option allows, if necessary, to switch the boiler unit into manual adjustment mode, without losing its productivity.

The performance of the boiler becomes the main one when choosing a boiler from the wide range

Popular fuel combination options

Various variations of combined heating units make it possible to solve various problems - from large-scale to less global problems. For example, they are able to provide hot water supply for a single family of 3-5 people, as well as heating an office building or an apartment building.

Option # 1 - gas / electricity combination

Electricity is the most effective for heating water.A rapid increase in temperature is due to exposure to the coolant, with the least share of delay.

The main priority quality of equipment with a combination of gas / electricity is its variability, which is manifested in the possibility of connecting to several heating systems, as well as the option of installing several circuits

Characteristics of combined heating appliances that provide significant advantages:

• Small sizes. The device has an oversized combustion chamber for burning gases, a heat exchanger with a built-in heating element or other type of heating device;
• Low power consumption. The boiler operates on gas, and the electric heater is put into operation only on demand - for quick heating of water or in the absence of access to gas supply;
• Low price category. This is achieved due to the absence of a separate combustion chamber - the heater is installed inside the heat exchanger. In equipment where there is no secondary circuit, the option of connecting a water heater is planned;
• TENY with a small power - many models on the market are designed only to support the specified temperature.

Although gas is an economical type of fuel, this cannot be said about electricity. Therefore, for houses located in an area with a poorly developed gas supply network, you should look at another version of the boiler that runs on different fuel.

Option # 2 - a combination of firewood / gas

More economical types of fuel are gas and firewood. The dimensions of the heating apparatus operating on such fuel are impressive - it has separate combustion chambers for each type of fuel.

Design features of boilers with a combination of gas / firewood type determine the placement of one or two heat exchangers. For the first case, it serves as a common element for all combustion chambers.

In case of interruptions in gas supply, the equipment will switch to electricity - for a month of such heating there will be a round in the payment for electricity

AT double-circuit boiler only one type of fuel is used to provide hot water. This type of combined boilers requires you to pre-issue permits for installation.

In addition, these boilers are divided into two subspecies: with a common and separate combustion chamber. The first option relates to installations created independently. They are used to minimize the final budget for the heating system of a country house.

With your own hands, a gas burner is installed in the classic boiler model, if solid fuel is used, it is dismantled. This option creates unacceptable working conditions for the heat exchanger - exposure to high temperature during burner operation. It is this that is a frequent cause of boiler malfunction.

When issuing a permit to install a boiler of a gas / firewood combination, the main aspects are the technical indicators of the solid fuel zone, which should not affect the gas

The design with separate chambers of the furnace is equipped with a dual-circuit system, one of which is used to heat water during heating, and the other to provide hot water.

In the event of a solid fuel boiler conversion for the use of diesel fuel, only blast burners are installed:

The transfer of solid fuel heating equipment to the liquid version will reduce costs without losing productivity. This solution is advisable if it is not yet possible to switch to the use of main gas. Still, diesel heating is 2-3 more expensive than gas.

Option # 3 - a combination of firewood / electricity

If it is impossible to connect to the main gas supply or the installation of heating cylinders are most often used solid fuel boilers. They have great power and are non-volatile.

Structurally, combined wood / electricity boilers are quite similar to gas models. Self-production of this type of device is also available. It will be enough to determine the required power, choose heaterand mount it into the heat exchanger.

Factory models of universal boilers for heating wood / electricity are equipped with a full set of necessary elements. They correctly designed the power and placement of the heating element, which leads to a high level of safety during the operational period

In addition to these characteristics, it is necessary to note the following features of combined heating boilers running on wood and electricity:

• auxiliary features - connection of the heating element block through the contact zone with the temperature controller or a special software unit that provides remote control of the boiler;
• increased breakage resistance - factory ones provide heat supply due to the operation of heating elements (heating elements) that can withstand high thermal effects during operation of the furnace compartment;
• maintainability - in case of failure of the electrical part of the boiler, it can easily be replaced. In many models of gas heat generating plants, such a function is not available.

The capacity of a solid fuel boiler is relatively slowly regulated. In connection with this feature, manufacturers recommend using the electronic part of the heating system to quickly adjust the heating level.

Option # 4 - multi-fuel plants

Design features of multi-fuel heating equipment for domestic use are based on the use of several alternative fuels. Such heating systems include models with the combination of pellet pellets / gas / firewood / electricity.

In most variations of pellet boilers of a combined type of heating, the burner is presented as a removable element, therefore its combustion chamber can be used for other types of fuel

The most significant structural feature of pellet combined heating boilers is the equipping with several combustion chambers, adapted to use one of the types of fuel - solid or liquid.

In addition to the functionality, it is possible to install an electric heating element located in the heat exchanger chamber.

Due to the easily removable pellet burner, it becomes possible to use other types of fuel, for example, diesel or gas.

For the application of this kind of energy, the necessary conditions for creating a forced draft pressure and certain structural features of the heat exchanger. All these characteristics are intrinsic. pellet boilers.

A multi-fuel heating system can be installed only after the following requirements are met:

• Uninterrupted power supply - a necessary condition for enhancing the operation of a pellet heating boiler, gas and diesel burners (the use of solid fuel materials is an exception);
• Organized supply of fuel materials to the boiler - this is the most acute problem when designing the installation of heating boilers with a combination of gas / firewood / electricity;
• Providing storage space for energy - for the use of balloon heating, external steel boxes are mounted or a separate room is allocated, and in some cases a building; diesel is stored in tanks connected to the pump unit.

Before purchasing universal heating equipment, it is necessary to analyze the main factors affecting the choice of a specific model.

So, the appropriateness of using each type of energy, because the cost of such a device is much higher than single-fuel systems.

The necessary diameter of the chimney must be calculated in advance, as traction coefficient must meet at least the minimum requirements for each fuel material

How to choose the right boiler?

The only objective criterion for choosing a combined boiler for your home is the necessary power to ensure the functioning of the heating system. Moreover, the number of connected circuits should not affect this indicator.

It makes no sense to pay more for a powerful boiler in the hope of adjusting its operation by automation. This approach contributes to the "idle" operation of the device, which leads to a faster failure. In addition, this mode of operation accelerates the condensation process.

As for the calculation of power, theoretically, for heating an area of ​​10 m2, 1 kW of heat energy will be required.

But this is a rather conditional indicator, which is adjusted based on such parameters:

• ceiling heights in the house;
• number of floors;
• degree of insulation of the building.

Therefore, it is advisable to use one and a half coefficient in their calculations, i.e. in the calculations, increase the supply by 0.5 kW. The power of a multi-circuit heating system is calculated with a premium of 25-30%.

So, to heat a building with an area of ​​100 m2, a power of 10-15 kW is required for single-circuit heating of the coolant and 15-20 kW for double-circuit.

To select a gas burner in a solid fuel boiler, you need to accurately measure the dimensions of the combustion chamber. It is to these proportions that the size of the gas burner will correspond

An equally important criterion when choosing a combined heating boiler is the price category. The price of the device depends on the power, number of functions and manufacturer.

Other characteristics are equally important for users:

• DHW
• material of manufacture;
• convenience in management;
• dimensions;
• components;
• weight and installation features;
• other things.

The issue of domestic hot water needs to be resolved immediately: will the boiler provide hot water or is there electric boiler.

In the case of determining the first option, a more preferable method is selected - accumulative or flowing, as well as the parameters of the water tank according to needs (calculated based on the number of residents).

As for the dimensions of the equipment, they only matter if they are installed in a room with a small area.

According to the manufacturing material, a wide range of boilers is presented. But the most popular options are steel or cast iron. Also, such a boiler is able to withstand high and long temperature load, has a higher service life.

Judging by the intensity of sales and relying on consumer reviews, the following models are actively in demand:

Automation of control affects usability, and the security system depends on how automated the process of energy combustion. Most models can be controlled using convenient remote controls or panels.

Most models are equipped with additional equipment. This may include the presence of a cooking surface for cooking, injectors, draft regulators, burners, noise insulation casing, etc.

Choosing a boiler for this parameter should be based on personal preferences and the amount allocated for the purchase.

When choosing a heating boiler with a combination of firewood / electricity, it is necessary to calculate the required power of the heating element. It is recommended to choose models with an indicator of at least 60% of the required coefficient for heating a house

But on the weight of the equipment and the complexity of its installation, you must immediately pay attention.

Installation in the residential building of most floor models of combined boilers for heating, equipped with several combustion chambers, requires an additional concrete pedestal, because the standard floor covering will not be able to withstand such a load. Optimal solution - equip a separate boiler room.

Knowing the main parameters that affect the choice of a combined boiler, you can choose the most suitable model.

Additional selection recommendations, as well as a comparative overview of different heating units for a private house, are given in this article.

Conclusions and useful video on the topic

The principle of operation of universal heating equipment in the video:

Rules for choosing a combined boiler in the video:

An example of a pellet combined heating boiler:

Regardless of the type of equipment chosen, it is necessary to design a future heat supply system before purchasing it. These include: pipelines, chimney and safety measures during operation of the heater.

This will ensure full functioning the system heating at the minimum cost on the energy resources.

Looking for an efficient combination boiler for your home? Or is there experience in using such installations? Please leave comments on the article, participate in discussions and share your impressions about the use of heating units.