Double-circuit wall-mounted gas boilers for heating a private house: the right choice at first glance

In an area without central heating and hot water supply, owners of private homes have to organize the work of these systems on one's own.

This requires a heat source, which is a double-circuit gas boiler. The larger the device, the higher its power., heavier in weight and larger in size.

Therefore, for large areas they are used floor unit, and for small private houses and even apartments - wall option. One contour such a device provides heating, and another — hot water supply (DHW).

Types of wall-mounted heating devices

Double-circuit wall-mounted gas boilers are:

• energy-dependent and autonomous;
• convection and condensation;
• with closed and open combustion chambers.

Energy dependent The devices operate using electricity. For them to work, the house must have an electrical network capable of withstanding the load from the boiler.

Autonomous The devices do not require electricity. Gas boilers can be used in a heating system with natural circulation.

In convection In boilers, water vapor after heating the heat exchanger is removed with smoke. In condensation - is passed through economizer, which generates additional heat.

Unit with open chamber combustion requires vertical chimney and a well-adjusted ventilation system in the room. For a unit with a chamber closed type a small one is enough coaxial a chimney (a pipe within a pipe) that exits onto the street through an external wall.

Gas boiler device

At the wall structure there are no global differences from the floor. The main difference is only in the installation method.

A wall-mounted gas boiler should not be heavy, so materials that can be found in a floor-mounted boiler (for example, cast iron) are not used. The wall-mounted version has power limitations.

Operating principle common to all gas boilers and consists of in gas combustion, after which the released heat enters the heat exchanger.

It gives it to the coolant (usually water), circulating in the circuit to which the radiators are connected. When a tap is opened in the kitchen or bathroom, a valve is triggered that redirects the coolant into the second circuit, designed for hot water supplyThis is how heating and hot water appear in a private house.

The work scheme deserves special attention. condensation gas boilers. They have higher productivity due to the additionally installed economizer, which, in addition to the heat from burning gas, also uses the heat of steam. But such units are more expensive than the widely used convection units.

Power of the device

The weight and dimensions of the boiler should not prevent its installation on the wall. The dimensions depend on its power. Usually, wall-mounted versions of gas boilers have average threshold 95-100 kW, which is suitable for a private house with an area of about 900 sq. m. Power of wall-mounted gas boilers — one of the key technical characteristics, because it is this that influences the amount of heat at which the house will be comfortable.

Photo 1. Wall-mounted gas boiler model Eco Four 24F, double-circuit, with a closed combustion chamber, manufacturer - "Baxi".

It is determined by calculation 1 kW per 10 sq. m, adding stock in 20%. This is due to the fact that working all the time only at maximum power, the device may fail. In addition, it is often required that the unit function all year round, and at different times different temperature levels are needed. Therefore, for year-round operation, two-stage boilers or devices with adjustable power are used.

Combustion chamber type

In wall-mounted gas boilers with two circuits cameras are used open and closed combustion types.

In the first case oxygen for the combustion process is taken from the environment naturally, so it should work well in the room ventilation. It also ensures the safety of the operation of the devices, removing combustion products from the room through a vertical chimney. Such units can work autonomously without electricity supply.

In the second In this case, air is forced into the chamber and removed from it using a fan through a small coaxial chimney.

Boilers with this type of chamber are safer for the environment, since they do not take oxygen from it and do not emit combustion products. However, for such a system to work power supply required.

Heat exchanger type

Wall-mounted gas boiler models use heat exchangers made of copper and stainless steel. Copper has high heat transfer and corrosion resistance. However, it is more susceptible to mechanical impact than steel. A stainless steel heat exchanger is stronger than copper, although it is inferior to it in heat transfer characteristics.

There are also bithermal heat exchangers that operate on the "pipe in pipe" principle: the heat carrier for heating flows through the outer pipe and heats the inner pipe through which the heat carrier for the DHW circuit flows. However, if very hot water is needed, then you can also use device with two heat exchangers: one for heating, another for hot water supply.

In most cases, such units combine one copper heat exchanger and one is made of stainless steel.

Choosing a wall-mounted boiler for a private home

When choosing a double-circuit boiler you need to be guided by goals, in which it is purchased.

For example, if the device is only needed for heating and hot water supply in the cold season, then a single-stage device operating at one power will be suitable.

For year-round use it is better to choose two-stage option gas boiler or a device with adjustable power.

Affects the choice gas boiler and building infrastructure. If there is no electricity and natural circulation of the coolant is not established, then an autonomous boiler will do. And if the house has all the infrastructure, including the Internet, you can use a device with electronic filling and remote control.

Required comfort level

One of the determining factors for choosing a wall-mounted gas boiler.

This includes the following capabilities:

• in sufficient quantity heat premises;
• provide DHW at the required temperature;
• demand minimum effort for maintenance;
• fit in design premises.

For example, small appliances with a coaxial chimney fit perfectly into the kitchen interior, being located in a niche near the outer wall (for the convenience of removing the chimney).

Automatic control

One of the ways to make the least effort to operate it. This control is best in electricity dependent devices.

This includes automatic ignition, gas supply shutdown in an emergency situation, and regulation of the operating intensity.

For example, programming the modes of a wall-mounted gas boiler allows in the absence of the owners save fuel and heat the room at a minimum level, and upon their return, restore comfortable parameters.

Chimney characteristics

To install a unit with an open combustion chamber, the chimney must:

• was vertical;
• had no more than two rotary couplings;
• had the length of one horizontal section no more than 1 m;

• 

  did not intersect with ventilation duct;
• was at a distance 25 cm from flammable building elements.

The chimney may be brick, metal or ceramic.

The practice of installing is widespread insulated stainless steel chimneys: they are distinguished by their affordable price, ease of installation, and efficient performance.

Which manufacturer to choose

The boiler manufacturer can play an important role throughout the entire life of the device. The fact is that any mechanism sooner or later it requires repair, and if the manufacturer is well-known and has its own service centers, then there will be no problems with spare parts and maintenance of the unit.

Among the manufacturers of modern devices are both well-known foreign and domestic brands: Bosh, Baxi, Buderus, NevaLux, Borinsky, Lemax.

Price

Cost of gas boilers is determined by the set of functions and materials for production.

The price range for domestic and foreign models fluctuates on average from 20 to 400 thousand rubles. Convection boilers are cheaper, condensing boilers are more expensive.

Most wall-mounted appliances are energy dependent, so for them electrical network requiredOn the other hand, this is a plus, since programmable models can be more expensive, but their price is offset by cost savings due to the electronically controlled operating mode. A boiler with an optimal set of functions for a medium-sized house can cost from 30 to 70 thousand rubles.

Features of operation

One of the important features of successful operation of the boiler is no heat loss in the room. No matter how good and powerful the device is, if there are many cracks in the house, the fuel is spent unproductively, and there is not enough heat in the room. Therefore, you cannot start the gas boiler until you are sure that heat loss is reduced to a minimum.

If the boiler is equipped programmable module, it can be left on during your absence.

For example, when the owners leave the house the unit will support minimum required temperature indoors, and upon returning, restore parameters that are comfortable for a person.

In the case of a double-circuit boiler, you should not use the DHW circuit too often, if the device has one heat exchanger. During the supply of hot water, the heating temperature decreases. In such cases, it is better to buy a device with two heat exchangers or connect a boiler to the DHW system.

Useful video

Watch the video to learn how to choose a gas boiler and when you should choose a double-circuit one.

Where to use a wall-mounted gas double-circuit boiler

The main advantage of a wall-mounted device is the availability of its installation in utility rooms private house and even apartment (for example, in the kitchen). If the area of ​​the building is not very large, then a wall-mounted boiler will cope with its heating and provide residents with hot water.

The disadvantages of using the devices include: use in it explosive fuel and the principle of operation, based on its combustion, which leads to the release of products harmful to the body.

However modern security systems In case of an accident, the gas supply is automatically shut off, and coaxial chimneys prevent smoke from entering living spaces.

The advantages of wall-mounted devices include their economy And ease of installationIn places where there is no central heating, using gas for space heating and hot water supply is associated with lower costs than electricity.

In this case, the boiler has a coaxial chimney takes up minimal space, does not require a separate room, ventilation or foundation, as is the case with a floor-standing gas boiler.