How to choose a gas wall-mounted double-circuit boiler: what to look for + what the market offers

The best inexpensive boilers

Low price does not always mean low quality. If the manufacturer saves on minor details that do not affect the operation of the boiler, such a purchase will be justified.

Lemax Premium-30

4.9

★★★★★
editorial score

89%
buyers recommend this product

See review

A 30 kW unit is suitable for economical homeowners for heating an area of ​​\u200b\u200bno more than 250 m2. The set of functions here is minimal, but all the necessary security features are there. The manufacturer abandoned the complex electronic filling, so the boiler is completely non-volatile - just connect it to the gas supply, and everything will work.

The floor model itself is made soundly, the heat exchanger inside is steel. And with an efficiency of 90%, Lemax consumes the minimum amount of blue fuel - no more than 1.75 m3 / h.

Advantages:

• Good build quality;
• Gas control;
• There is protection against overheating;
• Very economical;
• Heat carrier heating up to +90 °С.

Flaws:

Manual control.

To maintain the required temperature in the system connected to Lemax, constant monitoring will be required. Otherwise, there will be no problems with it, and a non-volatile boiler will save a lot of money.

Mora-Top Meteor Plus PK18ST

4.8

★★★★★
editorial score

88%
buyers recommend this product

See review

The Czech company Mora is known for its high-quality gas stoves. But the heating boilers of this brand are no worse. Here, for example, is a Meteor Plus wall-mounted single-circuit unit with a thermal output of up to 19 kW, a built-in expander and a circulation pump. It works flawlessly, consumes no more than 2.16 m3 / h of gas, has the entire minimum set of protective functions and at the same time costs much less than branded counterparts.

Advantages:

• Burner with automatic modulation;
• Low fuel consumption;
• Possibility of external control;
• Quiet operation;
• There is protection against overheating and freezing;
• Calmly transfers pressure drops of gas.

Flaws:

Not the highest efficiency (90%).

To install Mora, you will need a little more space than for compact Italian or German models, and this boiler loses to them in design. But Meteor fulfills its cost completely and is extremely simple to maintain.

Wall-mounted gas boilers: the main differences from the floor type

Wall and floor boilers have their pros and cons.

The wall view of gas boilers has recently gained large-scale popularity among the population, although previously only the floor version of the equipment was known. It's all about the following features and benefits of wall products:

1. Serious space saving. Floor-standing boilers are characterized by large weight parameters, due to their manufacture from cast iron. For the operation of such boilers, it was sometimes necessary to allocate a separate room (semi-basement type), where the boiler, expansion tank, etc. were placed.
2. No need for regular cleaning. In floor-standing boilers, a large amount of soot accumulates, which must be removed in a timely manner so that the operational performance of the equipment is at a constant level.
3. No need for the presence of an expensive chimney, which has to be made of brick or asbestos pipe in the case of using a floor type gas boiler. This option is not acceptable in the apartment.
4. No combustion of oxygen. In this case, the necessary air is supplied from the environment using a special flexible tube, which has a positive effect on the microclimate of the room.

Features of gas heating

Despite the presence of a large number of alternatives (electricity, diesel, diesel fuel, fuel oil, firewood, coal), it is gas heating that is still the leader in the world. And there are good reasons for this:

Profitability. Compared to other options, gas is relatively cheap and has a high efficiency. At the same time, not only the cost of the fuel itself is taken into account, but also additional costs for its storage (for the consumer), maintenance of the entire system, and so on.So, parts for rare types of boilers can be difficult to get, sometimes you have to overpay

This is also taken into account.
Minimum human involvement. Space heating with wood or coal requires mechanical addition of fuel

Here everything is automated, including the flow of gas and control of the flame.
Cleanliness, lack of soot, soot and other things. Boilers can be easily installed in the kitchen.
Possibility of heating large rooms. One powerful boiler can cope with a building on several floors.

At the same time, gas heating has its drawbacks. Or rather specific.

Installation must only be carried out by specialists

In particular, the installation of the boiler requires coordination with Gaztekhnadzor. You can entrust the installation only to an organization with a license that gives the right to provide such services.

In addition, you need to take care of ventilation. The products of combustion can be removed from the building in a natural way. But if there are problems with traction, you need to change the installation location of the boiler (which is not always possible) or provide it forcibly.

Which boiler is better to choose?

When choosing the best boiler, it should be borne in mind that each type of equipment is designed for certain conditions. Under which they will show maximum efficiency, allow you to achieve the expected result and level the shortcomings.

Therefore, it is so important to determine your requirements and take into account living conditions. So, if the equipment is selected in an apartment and there is no extra space for installation, then a double-circuit wall-mounted boiler will be an ideal option.

And although it is inferior in power to floor models, it is quite capable of meeting the needs of residents.

For a summer residence or a private house, where there is a separate room for the arrangement of a boiler room, a great solution would be to install a floor-mounted single-circuit gas boiler in conjunction with a boiler of the required volume. That will provide the needs of the family in hot water and heat.

When installing any model of a floor single-circuit boiler with a boiler, an order of magnitude more space will be required than for double-circuit analogues

And the load on the equipment in this case will be higher, so it is important to choose the right boiler power. If you are choosing a heating unit for a country two-story house or cottage, then in this situation it is best to stop at a powerful double-circuit floor-standing boiler with a built-in large-volume heater

If you are choosing a heating unit for a country two-story house or cottage, then in this situation it is best to stop at a powerful double-circuit floor-standing boiler with a built-in large-volume heater.

Floor-standing gas boilers with one and two circuits are more powerful than their wall-mounted "brothers". They are also mostly non-volatile. This is quite convenient, especially if there are power outages in the region.

We have given more recommendations and important criteria for choosing gas boilers in the next article.

Other types of heating boilers

In addition to gas, there are other types of boilers:

• electric;
• solid fuel;
• liquid fuel (diesel);
• combined.

electric boiler

The electric heating boiler is easy to operate, does not require fuel for its operation, this type of boiler has a high degree of safety. It is installed if the cottage, country house or apartment is located in a protected natural area where emissions of harmful substances are prohibited. Before choosing this type of boiler, you should think about the high cost of electricity. For comparison: 200 m² of area will require about 50 kW of power.

Liquid fuel (diesel)

Such boilers are not used for heating apartments. Diesel fuel is used as a heat source (it is considered an expensive type of fuel, and it is constantly consumed to maintain heat). The disadvantages include the characteristic smell of fuel, for this reason, liquid fuel boilers, as a rule, are placed in a separate building.

solid fuel

Such boilers are not installed in apartments for private use. In the modern world, solid fuel is used very rarely: it is difficult to imagine that a cottage will be heated with coal. However, now in stores you can find a heating boiler in which firewood, a special combustible product, coal, and wood waste are used as fuel. In terms of power, such boilers hardly reach 60 kW.

Combined

Allows the use of multiple fuels, such as gas and coal. Easy to use, especially in country houses and cottages.

Advantages of double-circuit gas boilers

Installing a wall-mounted gas boiler allows you to simultaneously solve the issue of uninterrupted supply of hot water and ensure optimal temperature conditions in the house. The main advantages of such units are:

• Small overall dimensions make it possible to install gas equipment not only in the private sector, but also in a city apartment;
• The cost-effectiveness of such systems significantly reduces utility bills;
• The price of a double-circuit installation is much lower than the cost of a single-circuit boiler with an indirect heating boiler.

In addition to these advantages, it should be noted that the design of modern wall-mounted gas boilers allows them to organically fit into any interior.

Advantages of wall-mounted gas boilers

The wall model is presented in the form of a housing device consisting of a gas heater, a technical device for heat exchange and electronics that control the unit.

Gas boilers are very advantageous, both in terms of reliability and practicality, as well as in terms of purchase and operating costs.

Providing hot water and heating with a hinged gas boiler has several advantages:

• Interesting design.
• Lightness and low weight. Suspended models are made of steel or copper. A separate room is not required for the arrangement of the unit. Compact dimensions allow installation under any furniture or device.
• High efficiency (90-94%), which leads to a reduction in energy consumption and energy savings. It is achieved thanks to the circulation pump and modulating burner included in the package.
• The autonomy of the functioning of the equipment does not require regular monitoring of the operation of the boiler.
• Low cost.
• The presence of additional devices (some models are equipped with two circulation pumps, a thermometer, a pressure gauge, safety sensors, etc.).
• Possibility of supplying hot water through an indirect heating system.
• Adaptation to work with different energy carriers.
• A diverse set of functions (pump blocking, protection against freezing and overheating, self-diagnosis, etc.).

Every year, more and more clearly, one can observe a trend towards preference for wall models.

Placement of the heat generator - requirements for the room

Heating gas-using equipment is much easier to install than to issue permits and put into operation. We propose to consider the first question - the independent installation of a wall-mounted gas boiler in an apartment or a private house. We gave the algorithm of actions for obtaining technical conditions and developing a project in the instructions for installing a double-circuit heat generator.

The requirements of the norms for the room for the location of the gas heating unit are as follows:

1. The heater must not be installed in living rooms and bathrooms. A hinged boiler may be placed in the corridor, in the kitchen and other non-residential premises on any floor, outdoor extension or a separate boiler room.
2. If a wall-mounted heat generator runs on a liquefied propane-butane mixture from cylinders or a gas tank, it cannot be installed in the basement of a private house.
3. The minimum allowable ceiling height is 2 m, the volume is 7.5 m³. If there is a natural gas water heater in the room, then the requirements become more stringent: the ceiling height should reach 2.5 m, the volume should be 13.5 cubic meters.
4. The room should have windows facing the street. The minimum dimensions of the glazed part are calculated as follows: we multiply the volume of the room by 0.03, we get the area of ​​​​the translucent structure in m².
5. When installing a furnace, supply and exhaust ventilation is required. Within 1 hour, the room air must be renewed three times (3-fold air exchange). To the volume of inflow, we add the air consumed by the burner for fuel combustion. In the kitchen, a window is made for ventilation.
6. The minimum distance from the front panel of the suspended boiler to the wall or other objects is 1250 mm (passage width).

The above rules apply equally to all types of heating units - wall and floor, with an open and closed combustion chamber. The installation site of the boiler must be agreed with the engineer who is developing your project. The designer will tell you where it is better to hang the boiler, given the location of the gas pipe.

Our expert will tell you more about the requirements for a gas boiler house in the video:

Connection diagram for boilers with two circuits

The main gas, to which urban residential buildings, enterprises and public institutions are connected, is the cheapest fuel. Even taking into account the paperwork and approvals in several instances, the installation of gas boilers justifies itself. A correctly selected model will be able to serve both the heating system and the autonomous DHW network.

The boiler is installed in a place convenient for maintenance. It is necessary to provide a safe connection of the gas pipe that meets the installation standards and lead the chimney to the outside for transporting combustion products.

Wiring diagram for a wall-mounted double-circuit boiler. Yellow line - natural gas supply, blue - cold water, red - hot water, purple and pink - heating circuit

Cold water is supplied to the boiler, after heating (when a certain temperature is reached), it is transported to the points of water intake, the main of which are a shower cabin, a bathtub, a sink in the kitchen. The in-house heating network is a closed circuit with a circulating coolant that serves the “warm floor” system, radiators, convectors and a heated towel rail in the bathroom.

When choosing a boiler, it is necessary to take into account its performance, since household-class double-circuit equipment is not designed to service a large number of connected water distribution and heating devices

An alternative to installing a two-circuit model is to install a 1-circuit boiler + BKN kit, where an indirect heating boiler serves the DHW system. This scheme is good because hot water of the required temperature is always present in the taps.

The disadvantage of installing a boiler is easily understood by owners of houses and apartments with a shortage of free space. Another drawback concerns the cost of a kit with a single-circuit boiler - it comes out more expensive than a double-circuit boiler

In double-circuit models, the heating system and hot water inside the device do not intersect, which gives its bonuses. For example, not a universal filler - water, but a special solution is used as a coolant.

Gas bypass selection options

Despite the similar principle of operation, different models differ in a considerable number of fundamental parameters.

Combustion chamber type

According to the type of combustion chambers, household gas heaters are divided into two types:

• with an open combustion chamber (atmospheric);
• with a closed combustion chamber (with forced air injection).

In the first case, the air necessary for the combustion of domestic gas is taken directly from the room in which the boiler is located. In the lower part of the combustion chamber, special holes are made for the inflow of fresh air.

Having participated in the combustion process, it, along with other decay products, enters the ventilation duct and exits through the chimney to the street. The construction of a chimney with good draft is a must for this type of boiler.

In the room where the boiler with an open combustion chamber is installed, there must be good ventilation, regardless of whether it is a kitchen or a boiler room.

In boilers with a closed combustion chamber, air is sucked in from the street with the help of suction fans, and the gaseous products of combustion are removed there by force. For such boilers, special coaxial chimneys are used. Exhaust gases are emitted along the inner contour, and fresh air is taken in from the outer one.

Expert opinion
Torsunov Pavel Maksimovich

Boilers with a closed combustion chamber are indispensable in cases where the construction of a full-fledged chimney with good draft is impossible. This type is relevant even for city apartments in old houses, when there is no connection to the central hot water system.

Dimensions and placement

All gas double-circuit valves are divided into two types according to dimensions and type of fastening:

1. Wall. The power of these devices usually does not exceed a certain limit - usually 50 - 60 kilowatts. The main trump card is compactness. Wall mounting practically does not take up usable area. You can place the device in the kitchen, providing a sufficient supply of ventilation in advance.Also, users of such devices are attracted by the aesthetics of execution - Italian and German products are distinguished by their elegant design. Wall-mounted boilers are suitable for use in houses up to 150 - 200 square meters, depending on the insulation and hot water consumption.
2. Floor. These devices are usually placed in a boiler room - a special technical room. It is easier to organize forced ventilation in it, and a rather noisy boiler will not interfere. For large houses with an area of ​​​​400 - 500 squares, powerful units are used that require installation in the basement or in a separate extension.

What type of gas boiler is installed in your home?

OutdoorWall

Heat exchanger configuration

The primary and secondary heat exchangers can be two elements spaced apart in the housing during installation or combined into one structural unit.

The separate system contains a tubular primary heat exchanger equipped with a radiator to improve thermal conductivity, and a secondary plate heat exchanger that combines a small heating circuit with tap water pipes.

The bithermic system consists of two tube circuits, one of which is placed inside the other. Typically, the outer channel serves to circulate the coolant, and water flows through the inner channel for the DHW system.

Power

The larger the area of ​​\u200b\u200bthe house, the more powerful the boiler needs to be. At the same time, in a double-circuit unit, only about 30% of the power is spent on heating, the rest goes to the rapid heating of DHW water. When calculating the power, it is necessary to take into account not only the water consumption, but also the degree of insulation of walls, roofs and floors, as well as the degree of cold penetration through the windows.

Small wall-mounted boilers for small houses start at 8 kilowatts, and powerful units for installation in a boiler room can consume more than 150 kW.