Dual circuit gas boilers - convenient way solve the problem of heating and supplying a private house hot water. They are easy to use, have the most high efficiency and reliability, the main thing is to choose a boiler that is suitable for its characteristics.
The functionality of double-circuit boilers is due to the features of their design. They are equipped with two heat exchange circuits, one of which heats the closed heating system, the second - water for household needs.
The heat carrier in the primary circuit is heated in the gas combustion chamber. Water for DHW systems is heated by the hot coolant from the primary circuit only at the time when you open the valve with warm water. At the same time, the valve built into the boiler shuts off the supply of coolant to the heating system.
Selection by types and parameters
Double-circuit gas boilers are presented on the market with a huge variety of models, and it is sometimes difficult to understand which one is better to choose. Therefore, for the right choice, you must clearly understand the characteristics you need.
These include:
- power, that is, the ability to effectively heat the desired area and heat a sufficient amount of water;
- boiler installation method - mounted (wall-mounted) or floor-mounted;
- type of combustion chamber, it can be open or closed;
- principle of operation - convection, requiring, or condensation, allowing the use of a coaxial chimney;
- degree of automation, type of ignition and the presence of protective functions;
- manufacturer and the degree of trust in him.
Power
It depends on this parameter whether the boiler is really capable of heating the house for a long time, efficiently and without overloads. Full-fledged heat engineering calculation, which is performed by specialists service department, must take into account all the features of the structure:
- wall material and degree of thermal insulation;
- number and total area of windows;
- ceiling height;
- the presence of complex elements - bay windows, glazed heated terraces, greenhouses.
It is quite difficult to perform such a calculation on your own, therefore, a simpler method is usually used. It is enough to calculate the total area of heated premises, and then apply the formula:
P = S 100 / 1000.
where P - required power, kW;
S - area in meters.
For separately standing house with insufficient insulation, this figure is increased by 15% in temperate latitudes and by 30% in the northern regions.
So, for an apartment of 120 square meters the nominal power of the boiler is 12 kW, but for a private house built in the Moscow region, it is better to choose a power of at least 15 kW, and for a colder region - 20 kW. This will allow the boiler to work without overloads.
You should also pay attention to the performance of the DHW circuit. To calculate the consumption of hot water, you need to know the number of water points in a private house and the likelihood of their simultaneous operation. At the same time, a flow rate of 400 liters per hour (6.6 liters per minute) is taken for each point. If two or more points are turned on at the same time, this indicator must be increased by the calculated number of times.
The total capacity of the boiler, sufficient to heat a private house and provide it with hot water, is the sum of the capacity of the heating system and the capacity of the heat exchanger for hot water supply.Wall or floor?
The installation method of the boiler depends on its power.: models designed for heating a private house up to 200-250 square meters are usually available in wall-mounted versions. They are compact and do not exceed in size, they can be placed in any convenient place, for example, in the kitchen or in the bathroom.
Such boilers are designed for a hot water capacity of not more than 14 liters per minute and can simultaneously provide two points of water intake. To reduce losses, it is recommended to install them close to hot water consumers.
Boilers with a total power of more than 20 kW are usually floor-mounted. Their dimensions and weight are superior to wall models, and it is better to place them in a boiler room with an equipped supply and exhaust ventilation system. The requirements for a particular model depend not only on the size, but also on the principle of operation and the type of combustion chamber.
Combustion chamber - which is better?
Gas boilers can be equipped with an open or closed combustion chamber. They differ in the way air is supplied to the combustion zone. In an open chamber, air is sucked in from the volume of the room in which the boiler is installed.
Therefore, they can only be installed in a boiler room equipped with a window or supply ventilation otherwise the air in the room will become unbreathable. In addition, to ensure stable draft and complete removal of flue gases for such a boiler, it is required with a height of the vertical part not less than that indicated in the passport.
The combustion chamber closed type allows you to install the boiler in any room of the house. To supply air and remove exhaust gases in this case, a coaxial chimney, consisting of two corrosion-resistant pipes located one inside the other. By inner tube flue gases exit, and fresh air taken from the street enters through the space between the pipes.
At the same time, fresh air is recuperated (heated), which has a positive effect on the combustion process. The coaxial chimney can be brought out horizontally through the wall. Thrust in this case is provided by a built-in fan. wall models usually have a closed combustion chamber, so they can be used not only for heating a house, but also in apartments. 
Principle of operation
According to the principle of heat removal, gas boilers can be convection and condensing. The difference lies in the fact that in convection, the coolant is heated in the combustion chamber, and in condensation, the heat obtained during the condensation of steam is additionally used.
A plus condensing boiler in its high efficiency- up to 96%. But him minus - strict requirements for the device heating system
: temperature return water, entering the heat exchanger, should not exceed certain values, usually 60ºС, which requires professional calculation and adjustment of the system and large expensive radiators. 
Energy dependence, degree of automation and type of ignition
Most simple models gas boilers do not require connection to electrical network. Their functionality, as a rule, is low - they have an open combustion chamber, require connection to a full-fledged vertical chimney, and their start-up is carried out only manually.
Modern models of gas boilers are connected to the mains, they are equipped with automation that allows them to work completely autonomously, without human intervention.
Two parameters important for usability:
- number of heating stages;
- ignition type.
The cheapest models are single-stage. In them, the heating process alternates with the standby mode. Upon reaching the set temperature, the boiler stops the combustion mode, and heating will start again only after the coolant has cooled to the lower allowable value. This may result in uneven heating.
With two- and three-stage heating, the boiler automatically selects the combustion intensity depending on the set temperature, so that the coolant does not overheat and the room temperature remains stable. The price of such models is slightly higher.
Ignition type in gas boilers sometimes manual- using a piezoelectric element, or electronic- in models equipped with a control unit. Piezo ignition after shutdown requires manual start, the electronic one turns on itself after a break in the power supply or elimination of the emergency operation of the boiler.
Other convenient features built into the gas boiler help make its operation completely safe. They are equipped with almost all modern models boilers. Such functions include control of the flame, draft, gas flow and other modes of combustion and heating system.
You can find out by the codes that are reflected on the display of the electronic control unit, some models also allow you to connect a GSM notification system via SMS.
Famous brands and manufacturers
Focusing only on the equipment manufacturer is not entirely correct, since most companies have a wide range of models with a wide variety of functions. But buying gas equipment from an unknown manufacturer, even with a high-quality assembly, carries a number of risks. That's why When choosing a manufacturer, you should pay attention to the following nuances:
- warranty period and period of use of equipment;
- location service centers where repairs or maintenance can be made;
- the ability to buy or order spare parts and consumables;
When choosing a gas heating equipment As a rule, we are faced with a dozen questions that relate to the characteristics and parameters of this equipment. And, on how accurately we will be able to answer the question, "what kind of boiler do we need?" depends on how efficient heating equipment we purchase. Almost every one of us knows that gas boilers are divided into several classifications and categories. Just how to do right choice, and, in favor of which boiler - with open cam combustion or closed, give preference?
Gas boilers with an open combustion chamber
Gas boilers with an open combustion chamber or, as they are also called, with natural draft - are good example the classical scheme, when the air necessary for combustion and operation of such equipment is taken directly from the room in which such a boiler is installed. In other words, the equipment independently consumes the necessary dose of air that it needs for the subsequent combustion of gas in a special compartment. gas boiler. And, here the exhaust gases and combustion products are discharged through the chimney opening, the presence of which, in this case installation of such a boiler with a closed combustion chamber is mandatory.
The main disadvantage of installing just such a boiler is the fact that if the boiler is installed in residential premises, and in case of insufficiently good ventilation in the room, there may be a lack of oxygen, a feeling of stuffiness and even cases of carbon monoxide poisoning. That is why, experts recommend that in the case when you opt for purchasing a boiler with an open combustion chamber, take care in advance to allocate a specially designed for such equipment small room- furnace. It must meet all the necessary requirements of your heating equipment, be suitable in size and be equipped in accordance with the necessary safety regulations. This room you also need to dress up to equip with a vertical chimney and ventilation (providing 3x air exchange). Such a mini-boiler will become a guarantee and guarantee of the safe operation of a boiler with an open combustion chamber.
As for the price parameters, the cost of boilers with an open combustion chamber is an order of magnitude lower, and it is among the boilers with an open chamber that there are boilers that do not depend on the availability of electricity.
Gas boilers with a closed combustion chamber.
At first glance, when you opt for just such a combustion chamber in heating equipment, you make your life much easier. As a rule, you do not have to additionally equip a room for a mini-boiler room in order to install such a boiler there (although the basic requirements for the room where such a boiler is installed will have to be met). And, in the case when you are a little limited in space - this is a significant plus, it will be enough just to take a few square meters in order to install such a boiler with a closed combustion chamber there.
However, what about the air supply and smoke? Where does what come from and where does it go? In fact, there is nothing complicated in such a closed combustion chamber. Such boilers really do not need a vertical chimney, or a room specially designed for their installation.
However, the removal of combustion products in such gas boilers, if desired, is also carried out by horizontal smoke removal, using the work powerful fan or cooler. The same fan supplies required amount oxygen to keep your boiler running. However, the presence of a fan already implies a certain energy dependence, and such gas heating boilers cannot work without electricity.
Boilers with a closed combustion chamber for combustion take air forcibly from the street, simultaneously heating it with combustion products, which significantly increases the overall efficiency of the boiler. You will also need to install a special coaxial chimney. What it is? Such a chimney is equipped and works according to a very simple principle - a pipe in a pipe. So, the air necessary for combustion is taken not from the room in which such a boiler is installed, but from ... the street, using the installed external pipe. As for the products of combustion, they are also thrown out through a tube (this time internal) of such a coaxial chimney.
This option not only frees you from the need to install additional ventilation systems, but you also get some more important advantages: - the safety of such a coaxial chimney is an order of magnitude higher than the safety of an ordinary chimney. This is achieved due to the fact that the combustion products pass through the inner tube and cool down during their passage due to the fact that outer pipe cold air is coming in.
- the efficiency index of such heating devices is much higher.
- the same high efficiency index indicates that afterburning gas fuel goes much better, which means that the environmental friendliness of such gas heating equipment is also much higher.
- since the combustion cycle is carried out completely isolated from the room in which such a gas boiler with a closed combustion chamber is installed, both safety and the level of comfortable stay in such a room.
As for the cost of boilers with a closed combustion chamber, they are an order of magnitude higher in cost compared to boilers with an open combustion chamber, and they are noisier.
First of all, it is worth noting:
- absolute safety of use;
- high productivity and efficiency;
- oxygen is not burned;
- Rich parameter control functionality.
In other words, such models are great for apartments. multi-storey buildings, as they can be used in small-sized rooms, without bringing any negative impact on human health. High performance and rational use energy resources are the main advantages of boilers of this type.
Wall-mounted double-circuit gas boilers with a closed combustion chamber
Double-circuit models with a closed combustion chamber, capable of using outdoor air to ensure the process of work, are the safest and easiest in terms of operation. In the process of installing them, you do not have to worry about the problems of correct footage or work. natural extract.
The price of a double-circuit wall-mounted gas boiler with a closed combustion chamber partially depends on the situation on the foreign exchange market, since most models of heating equipment are supplied from abroad.
For apartments and small houses a single-circuit wall-mounted gas boiler with a closed combustion chamber is excellent, floor version more often used for heating rooms with a larger quadrature.
Wall-mounted single-circuit gas boilers with a closed combustion chamber
Specifications wall-mounted, floor-standing single-circuit gas boilers with a closed combustion chamber you will find in our catalog, where all necessary information about each particular model. Often this modification is used with the use of coaxial chimneys, which provide both the process of supplying air from the street and the exhaust gas output to the outside. The operation of such a mechanism is impossible without forced ventilation, which is installed in the chimney itself.
It is very easy to buy a wall-mounted single-circuit gas boiler with a closed combustion chamber using the one-click order form. In other words, you will save not only your money, but also precious time. The Technodom online store also presents turbocharged models with a closed combustion chamber from the best manufacturers. To get the necessary advice about the characteristics of a particular boiler or delivery conditions, call the indicated phone numbers or order a call back.
Chosen for home heating gas heating is different a large number parameters. Choosing the right boiler among the proposed models, taking into account the climatic features of the area of \u200b\u200bresidence, is a rather difficult engineering task. First of all, it is necessary to distinguish among the selected equipment groups that are fundamentally different from each other in parameters. Among them, two large groups of boilers stand out:
- With an open combustion chamber,
- With closed combustion chamber.
Each of these groups has its pros and cons, certain requirements for placement.
Consider the advantages and disadvantages of boilers with a closed combustion chamber.
Such boilers are very convenient equipment that requires a minimum of attention from the owner in everyday use.
- A separate room is not required for the installation of a wall-mounted or floor-standing boiler. They are compact, aesthetic, easy to maintain, inexpensive. They can be installed in the bathroom, in the kitchen, even in the hallway. An area of a few square meters (and even less for wall-mounted boilers) is quite enough to place equipment that will provide heat in the house and hot water in the taps.
This quality is very valuable for small apartments and homes where living space is limited. Naturally, the minimum fire safety requirements to the premises for the placement of such boilers exist.
- Not required for exhaust gases vertical chimney. A horizontal coaxial pipe is sufficient. The boiler is equipped with a fan powered by electricity. The fan creates forced draft, removes the results of combustion and supplies fresh air.
Air intake is carried out from the street from the room through coaxial pipe, the exhaust gases are discharged by the fan to the street through the same pipe and along the way in the pipe begin to cool. Therefore, no additional ventilation equipment. The use of boilers of this type is absolutely safe.
- Due to the air intake for combustion from the street, boilers with closed system have more high efficiency are more fuel efficient than open systems.
The only disadvantage of closed system boilers is the dependence on electricity, since it is used to ventilate and ignite the burner flame. In the event of a power outage or malfunction, there is a danger of quickly freezing the house if there is a severe cold outside.
There are two ways to get rid of this disadvantage:
- provide for the possibility of heating with wood during a power outage using a stove or fireplace, which can quickly heat a small room;
- buy a gas generator or UPS;
The design of the coaxial chimney
For normal functioning a boiler with a closed combustion system requires a coaxial chimney. Such a chimney consists of pipes different diameter, inserted one into the other, and is called a “pipe in a pipe”. Through a large pipe, fresh air enters the boiler from the street, and through a pipe of a smaller diameter, exhaust gases are discharged into the street. Hot gases, surrounded by low temperature outdoor air, are rapidly cooled.
A successful engineering solution made it possible to do without installation additional ventilation in the room where the boiler is located. Since the air is not taken from the room for fuel combustion, and the exhaust gases are immediately removed, the combustion products do not spoil the atmosphere in the house, and efficient combustion of the fuel is ensured.
Heat exchangers
The main element of heating boilers are heat exchangers. It is the heat exchangers that are designed to transfer energy from the burnt fuel to the coolant. Naturally, metal is used to perform this function:
- Steel - Steel heat exchangers are easy to manufacture and therefore inexpensive. However, steel rusts, so the service life of steel products is short and the weight is large. The efficiency is inferior to all other materials. Steel Products Prefer domestic producers boilers;
- Copper is very comfortable material for the heat exchanger, does not give in to corrosion, quickly heats up and cools down. Copper heat exchangers are most often used in imported boilers;
- Cast iron is also not subject to corrosion, but due to brittleness and insufficient care, cracks appear on it. Cracks can also appear due to uneven heating during the formation of scale during long-term operation.
Mandatory flushing of the coolant. If the carrier is water, then once a year. If antifreeze, then every two years.
Single and double circuit boilers
Single-circuit models have one function - heating the house. Double circuit model in addition to heating supplies hot water to households. The main advantage of single-circuit boilers is a much lower price. You can buy additional equipment for hot water, but in this case, the cost of additional equipment and a boiler, the complexity of installation, balances or even exceeds the cost of double-circuit boilers. Optional equipment is included in the harness and becomes part of it.
Single-circuit boiler:
- Independence from water pressure;
- Constant supply of hot water;
- There are no restrictions on the amount of hot water consumed in all taps.
Double-circuit boiler
- The cost of a double-circuit is lower than a single-circuit with a boiler;
- Takes up very little space, compact;
- No additional equipment required;
- Ease of installation;
- Efficiency - only the amount of water that is required is heated.
- Variation in hot water temperature. When the valve is opened, the water starts to heat up. Since the water is flowing, the heating occurs gradually from cold to hot. The temperature of the water is affected by the pressure in water pipes. The lower it is, the colder the water from the tap flows;
- The water temperature immediately drops if several taps are open at the same time;
- The farther away the tap is from the boiler, the longer you have to wait for the water to become hot. Therefore, the flowing water is simply poured into the sewer until it is heated to the right temperature;
- The second circuit is turned on only when the water flow is significant. Otherwise, the second circuit with a small stream may not turn on. Because of this feature of dual-circuit modules, water is difficult to save.
Dont Have such a disadvantage devices with storage tank up to 60 liters or a layered heating boiler. They supply water at a constant temperature, regardless of the pressure in the water supply.
Floor boilers
Additional space may be required to place floor boilers, as they have more power and are larger than wall-mounted ones.
Floor boilers, pluses:
- The heat exchangers in them are made of cast iron, which increases the weight of the product, but has a long service life - up to 30 years. Other inexpensive parts are easy to replace during operation;
- A chimney with reinforced draft is not required.
- Due to the cast-iron heat exchanger, it takes up a lot of space on the floor, since the weight and dimensions do not allow hanging the boiler on the wall;
- Requires purchase and installation expansion tank, the heater is tied;
Wall mounted boilers
Wall-mounted heating boilers – perfect option for heating city apartments and individual cottages. Installation of wall-mounted boilers of both types (single or double-circuit) is not difficult. It is also easy to maintain them.
Uninterruptible power supply or generator?
The main disadvantage of a wall-mounted boiler - the inability to work without electricity can be easily eliminated in two ways:
- By purchasing an electric generator (gasoline or diesel). But it must be borne in mind that electricity generated by conventional generators is not suitable for imported boilers with a closed system. In order for the boiler to make friends with the generator, a stabilizer is also required, which converts the generated voltage into desired view sinusoidal waveform with stable standard values.
- By purchasing an uninterruptible power supply (UPS). Because the wall boilers consume, as a rule, insignificant electrical power to ignite the burner flame and operate the fan, then when the mains voltage is turned off, you can use an uninterruptible power supply, and not buy a generator for this.
UPS advantages:
- silent operation
- ease of connection
- no operating costs
- opportunity to provide offline mode work for a long time,
- no need for consumables.
If the UPS is made using “onlain” technology (double converter), then it produces a “pure sine” not only in battery mode, but also from mains voltage.
IMPORTANT!In order to ensure the operation of heating for tens of hours, it is necessary to choose a LongTime (LT) configuration device. It has no internal battery and is supplied with charger increased power. Batteries of the selected capacity are connected to the UPS.
The capacity of the batteries is selected depending on the time during which the UPS will support the operation of the heating boiler.
In practice, the power of home wall-mounted boilers ranges from 50 to 300 watts. This corresponds to a current strength of 70 to 400 volt-amperes.
Installation and maintenance of boilers with a closed system is not difficult.
Therefore, most consumers, when choosing a heating system for their country houses tend to choose wall-mounted boilers with a closed combustion chamber
One of the main differences between household gas heating boilers running on fuel from electric thermal installations (electric boilers) is the presence of combustion products that are removed through the flue.
The normal process of removing gases occurs due to gravity, that is, due to gravitational force, or with the help of excess pressure, which is created in the furnace by an air fan.
A different approach to the issue of removing combustion products requires different approach to constructive solutions when creating combustion chambers. Therefore, all combustion chambers of heating household appliances subdivided into
Pros and cons of boilers with an open combustion chamber
Boilers with an open combustion chamber are equipped with a gas atmospheric burner, that is, the air is taken from the boiler room. This type of construction allows smoke and carbon monoxide to escape with minimal resistance. thermal plant. Almost all boiler units AOGV, AKTGV, Alphatherm, Protherm, Baxi, presented on the Russian specialized market, are arranged according to this principle. These heat generation systems used for heating and hot water supply are characterized by low cost, structural simplicity, ease of installation and maintenance.
The disadvantages of such thermal installations include the need for a vacuum at the outlet of the boiler. So, at low atmospheric pressure or in the case of a clogged gas duct, the risk of tipping over and the penetration of combustion products into the living room increases. To avoid this, heating and hot water boilers with an open type combustion chamber thrust sensor, turning off the gas supply at a high concentration of combustion products in the boiler room. Experts recommend additional equipment boiler roomgas alarm.
Advantages of boilers with a closed combustion chamber
Heat generating plants with a combustion chamber closed type have more complex structure. The air intake is forced from the street, and the efficiency of these heating installations higher, due to the "improved" surface of the heat exchanger. Boiler equipment of this type are performed single and multi-way. The use of closed chambers made it possible to increase their power to 60 kW, without sacrificing compactness.
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