In the housing market, private houses and apartments in multi-storey new buildings that have autonomous heating systems and water heating for their own needs (DHW) are especially valued. For autonomous heating of houses, various water heating equipment is used, but a single-circuit gas boiler is especially popular. And this is thanks to its simplicity and safety.

Advantages

Modern models gas boilers with one heating circuit for heating the heating system could be called primitive water heating devices if they were not equipped with high-precision control and monitoring equipment to ensure the reliability and safety of all operating cycles. To solve the problems of regulation and safety of boilers, an automatic boiler protection system with gas flow and pressure regulators, fittings that regulate the flow, temperature and pressure of heated water, all kinds of sensors, instruments and safety devices is aimed. This is the main advantage of gas boilers.

Other important benefits:

• simplicity of design and installation of the boiler, which includes a combustion chamber with a gas burner, a loop heat exchanger in the firebox, a system of manifolds and pipelines, and pumping equipment;
• efficiency achieved by automation and adjustment work for optimal and efficient combustion of fuel, mixing processes and regulation of coolant parameters in accordance with standards;
• the ability to connect boilers to cascade heating systems within cities and large towns, which allows not only to centrally control the system, but also to ensure reliable and high-quality heat supply to consumers in residential areas, neighborhoods, microdistricts, as well as enterprises whose boiler houses are included in the cascade;
• more environmentally friendly emissions of gas combustion products into the atmosphere compared to similar boiler houses using liquid and solid fuels.

Operating principle

The working circuit of the heating boiler is formed by the following elements:

• its own water heater (heat exchanger), located in the combustion chamber and heated by hot gas combustion products, which enters the furnace through the burner;
• a return pipeline supplying the boiler heat exchanger with cooled coolant (water) from the heating network;
• a direct pipeline of heated water leading from the heat exchanger to the heating system;
• a circulation pump that drives the coolant in a circle.

That's the whole concept diagram of the working cycle of a single-circuit boiler. Make-up (compensation for inevitable water losses) of the heating system of small boiler houses is usually carried out from the city water supply, which has a pressure in its pipelines higher than the pressure in the heating system.

The functional limitations of a single-circuit boiler, expressed in its use only for heating, is a significant disadvantage compared to its double-circuit “brother”.

But if the boiler is combined with an indirect heating boiler and thereby provides the consumer with hot water for domestic needs, then the capabilities of the boilers are equalized.

Subtleties of work

If, when searching for heating equipment for your own home or apartment, the choice stops at a single-circuit boiler and you plan to connect a boiler to it, then the following features of the operation of the boiler in tandem with this heat exchanger must be taken into account.

1. From the moment the boiler is turned on until the water in it is completely heated, the heating system will not work. Based on this problem, it is necessary to choose a hot water supply heat exchanger according to the maximum water heating time, which would be enough to prevent freezing of heating pipes in the extreme frost of the region where you live.
2. Choose a boiler based on power, connecting it with the heated area of ​​​​the premises, not forgetting about the climate zone of residence, what the house is built from and whether its walls have thermal insulation - all this is important when choosing the power of the heating unit.
3. Having decided on the power, you can say with accuracy whether such a boiler will handle a boiler water heating system or not.

Heating specialists believe that a boiler installation can only function normally with a boiler with a power of at least 24 kW. Another expert figure is that the boiler takes up to 50% of the power from the boiler. These are the numbers you need to focus on when choosing a gas boiler model for your home. And avoid a situation where a 35 kW boiler is installed with an estimated heating power consumption of 25 kW, and the boiler takes 17 kW. As a result, a boiler power deficit of 7 kW is formed.

It is also worth noting the fact that in some cases a boiler with high performance is required, with a capacity of 200 or even 500 liters.

Such boilers are produced with built-in circulation pumps for domestic hot water.

Types

Manufacturers of water heating devices do not skimp on developing cutting-edge models, having correctly taken into account the public interest in autonomous heating and hot water supply devices for private homes that emerged several years ago.

Currently, there are two types of single-circuit heating devices:

• floor;
• wall-mounted

Floor-standing options are more powerful, but their placement requires separate rooms in the form of an extension. Wall-mounted water heater – compact, small-sized, installed on the wall. That is why the first of these models became widespread among owners of country and city private houses, dachas and cottages, and wall-mounted boilers found their admirers in urban areas.

Both boilers have a simple and understandable design, attractive appearance, high degree of security. You only need to form your own opinion about which ones are better depending on the tasks they face. Sometimes it is more profitable to purchase a single-circuit wall-mounted unit with less power, but which is enough for a full-fledged heating system at home, and make a simple connection to connect the wall structure to a column used to heat cold water for your own needs (the column can be electric or gas). The hose tying kit can be purchased separately.

Why do you need a hot water boiler for a double-circuit gas boiler or water heater?

For heating and hot water supply (DHW) of houses and apartments, owners often install double-circuit gas boilers or geysers. A DHW system with such a boiler (column) is relatively cheap and takes up little space.

However, after some time, the owners begin to be annoyed by the shortcomings in the operation of hot water supply with a double-circuit boiler (column).

Flow-through heat exchanger for hot water supply of a double-circuit boiler (column) begins to heat the water at the moment the water is drawn when the hot water tap is opened.

All energy spent on heating passes from the heater to the water almost instantly, in a very short time of water movement through the heater. In order to obtain water at the required temperature in a short period of time, the design of an instantaneous water heater provides for limiting the speed of water flow. The water temperature at the outlet of the flow-through heater depends very much on the water flow — the size of the stream of hot water flowing from the tap.

To heat an economy class home, a lower power boiler is usually sufficient. That's why, choose the power of a double-circuit boiler based on the need for hot water.

A DHW circuit with a double-circuit gas boiler or water heater cannot provide comfortable and economical use of hot water in the house for the following reasons:

• The temperature and pressure of water in the pipes very much depend on the amount of water flow. For this reason when you open another tap, the water temperature and pressure in the hot water system changes significantly. It is very uncomfortable to use water even in two places at the same time.
• When the flow of hot water is low, the instantaneous water heater does not turn on at all and does not heat the water. To obtain water at the required temperature, it is often necessary to use more water than necessary.
• Each time the water tap is opened, the double-circuit boiler or column restarts, constantly turning on and off, which reduces the resource of their work. Frequent re-ignition of the burner reduces the efficiency of the water heater and increases gas consumption. Each time, hot water appears with a delay, only after the heating mode has stabilized. Some of the water goes down the drain uselessly.
• The power of a gas boiler (heater) in DHW mode often turns out to be more than necessary, which leads to cycling (clocking) of hot water heating. The boiler (column) burner in DHW mode periodically turns on and goes off. Accordingly, consumers there is either cold or hot water, and also all the disadvantages of frequent re-ignition of the boiler burner indicated above appear. To eliminate clocking, water flow is usually increased beyond what is necessary.
• In DHW systems with a double-circuit boiler it is impossible to recirculate water in the distribution pipes around the house. The waiting time for hot water increases as the length of the pipes from the boiler to the water collection point increases. Some of the water at the very beginning has to be drained uselessly into the sewer. Moreover, this is water that has already been heated, but has managed to cool down in the pipes.

Ultimately, the use of a double-circuit boiler (column) in a hot water supply system leads to an unreasonable increase in water consumption and the volume of sewage waste, to an increase in electricity and gas consumption for heating, as well as to insufficiently comfortable use of hot water in the house.

A hot water supply system with a double-circuit boiler is used, despite its disadvantages, for the reason relatively low cost and small size equipment.

A heating and hot water system with a single-circuit boiler and an indirect heating boiler is more economical and comfortable.

But what to do if a double-circuit boiler or water heater is already installed in a house or apartment, and the owners are not satisfied with the operation of the hot water supply system, and they want to get rid of its shortcomings.

Three options for connecting a boiler to a double-circuit gas boiler or water heater

1. There is an option to purchase indirect heating boiler, with a heat exchanger inside, and connect it to the heating circuit of a double-circuit boiler. But the cost of such a boiler and additional equipment for its connection and piping is quite high. This option is not discussed in this article.

2. I recommend installing in a DHW system with a double-circuit boiler or water heater stratified heating boiler. This boiler does not have a heat exchanger, which significantly reduces its cost.

3. Or, in a DHW circuit, between a double-circuit boiler (column) and hot water consumers, install electric storage water heater- boiler. This option does not eliminate all the shortcomings of the hot water system, but it can significantly improve the comfort of using water.

Connecting a storage electric hot water heater to a double-circuit gas boiler

The most in a simple way To improve the DHW system with a double-circuit gas boiler or water heater is to install an electric storage water heater - an electric boiler.

Connection diagram for an electric hot water boiler to a double-circuit gas boiler, as a storage buffer tank between the boiler and consumers.

An electric boiler is used as a buffer tank between the boiler and hot water consumers. From the DHW circuit of a double-circuit boiler, hot water enters the electric boiler before reaching the consumer. Hot water is supplied to the water taps from the boiler.

Electric storage water heater - a boiler is used to store a supply of hot water heated by a gas boiler. In addition, the temperature of the water in the boiler is maintained at a given level by turning on the electric heating element. The inclusion of the electric heater is controlled by the boiler thermostat.

In the diagram, on the water supply pipe from the boiler to the boiler, a block of two valves is installed - a check valve and a safety valve. Valves are usually sold complete with an electric boiler.

Check valve prevents water from leaving the boiler when water disappears in the water supply.

Safety valve relieves excess pressure from the hot water system associated with the expansion of water when heated. A small amount of water periodically leaks from the valve which needs to be disposed of somewhere.

In addition, the electric boiler manufacturer prescribes regularly, every two weeks, checking the serviceability of the valve by manually actuating it. In order to avoid these problems, I recommend additional install an expansion tank for hot water supply, which will compensate for changes in water pressure in the DHW system.

Safety valve response pressure 6 - 8 bar, depending on the boiler model. If the water pressure in the water supply system is greater than the valve response pressure, then water pipe you need to install pressure reducing valve. The valve is set to reduce the outlet water pressure - no more than 80% of the safety valve response pressure.

The DHW circuit with a gas double-circuit boiler (boiler) and an electric storage water heater - boiler is somewhat popular due to its simplicity and lower cost. There is no circulation pump in the circuit; you can use a regular electric boiler; the amount of fittings for piping is also minimal. But operating a DHW system with a buffer electric boiler has its drawbacks.

Advantages and disadvantages of a hot water supply system with a buffer electric boiler

DHW circuit with buffer electric boiler ensures stable water temperature at the outlet to consumers, including at low water consumption and when the boiler is clocked. The water temperature in the boiler can be set above 60 o C , (temperature produced by the boiler). Using hot water will become more comfortable, but you will have to pay for it with higher electricity consumption.

The circuit with a buffer electric boiler has three main disadvantages.

First of all, it's quite significant energy consumption for heating water. Electricity is spent to compensate for heat losses (water cooling) when storing hot water in the boiler, as well as to heat that part of the water that flows from the boiler into the cold boiler.

Some of the water from the boiler enters the boiler cold. This happens during the start of the boiler’s DHW mode each time the water tap is opened, as well as in the case of boiler cycling. Besides, cold water from the boiler to the boiler is supplied in the case of insignificant hot water consumption, when the flow rate is less than the minimum threshold required to start the boiler in DHW mode.

Electricity is also spent on heating water, if the boiler thermostat is set to a temperature above 60 o C.

The second drawback is that the boiler’s DHW mode is still turned on every time the water tap is opened. Boiler clocking is not eliminated, but only becomes invisible to the consumer. All this, as mentioned above, reduces the boiler’s operating life, and frequent re-ignition of the burner reduces the efficiency of the boiler and increases gas consumption. Some owners find it beneficial turn on the DHW mode on the boiler only when taking a shower or filling the bath. For washing dishes and in other cases when the need for hot water is small, the water in the boiler is heated only by electricity.

Thirdly, the dependence of the pressure in the hot water pipes on the water flow remains, since water from the water supply continues to pass through the flow limiter in a double-circuit boiler or column. For this reason, when the second water tap is opened, the temperature of the water in the first mixer may change, although not so much.

Choosing an electric boiler for a hot water supply system with a double-circuit boiler or water heater

To get the benefits of using hot water from a hot water system with a boiler and an electric boiler, it is enough to install a small-capacity boiler, 30 (50) liters. In addition, a small boiler will consume less electricity than a large one.

I recommend choosing an electric boiler with a cylindrical stainless steel tank. The boiler is often installed next to the boiler or water heater. To ensure that the dimensions of the boiler do not go beyond the dimensions of the boiler, it is convenient to use electric water heaters with a vertical tank of small diameter. The brand name of such boilers usually contains the word Slim.

I recommend, Thermex Ultra Slim IU 30 (or 50) V has a stainless steel tank, a metal body, three stages of heating element power 0.7/1.3/2.0 kW., maximum outer diameter 285 mm., and height 800 (1235) mm., mechanical control. Warranty - 7 years.

Electric storage water heaters with a flat body shape should not be chosen. In the housing of flat water heaters, two cylindrical tanks of small diameter are installed side by side and connected to each other by pipes. Such complex design creates problems ensuring their durability, with the distribution of water temperature in the tanks, and also increases their price.

At the end of this article you will find DHW circuit with boiler and hot water recirculation, as well as recommendations for choosing equipment.

Where and how much to buy an electric boiler in your city

Cumulative electric water heater Thermex Ultra Slim IU

DHW system with a double-circuit boiler (or column), but with a layer-by-layer heating boiler eliminates all the disadvantages.

Operating principle of a DHW layer heating boiler

Last time The hot water supply system with a layer-by-layer heating boiler is gaining popularity, the water in which is heated by a flow-through water heater. This boiler does not have a heat exchanger, which reduces its cost.

Hot water is drawn from the top of the tank. In its place, cold water from the water supply immediately flows into the lower part of the tank. The pump drives water from the tank through a flow-through heater of a gas boiler or water heater, and supplies it directly to the top of the tank. Thereby, The consumer gets hot water very quickly— you don’t need to wait until almost the entire volume of water warms up, as happens in an indirect heating boiler.

Rapid heating of the top layer of water, allows you to install a smaller boiler in the house, as well as reduce the power of the flow-through heater, without sacrificing comfort.

Manufacturers produce double-circuit boilers with a built-in or remote layer-by-layer heating boiler. As a result,the cost and dimensions of the DHW system equipment are somewhat smaller,than with an indirect heating boiler

The water in the boiler is heated in advance, regardless of whether it is spent or not. The hot water reserve in the tank allows you to use hot water in the house for several hours.

Thanks to this, the water in the tank can be heated for quite a long time, gradually accumulating thermal energy in the hot water.

Long duration of water heating allows use a relatively low power heater.

Scheme of operation of a layer-by-layer heating storage boiler with a double-circuit boiler

Schematic diagram connecting a stratified heating storage boiler to a double-circuit boiler

In the diagram, arrows show the direction of water movement in the DHW circuit of the boiler during operation of the circulation pump. The pump is turned on by the temperature sensor, boiler thermostat.

The circulation of water in the DHW circuit of the boiler starts the boiler in DHW mode. The water heated by the boiler enters the boiler, where it rises. Cold water from the bottom of the boiler is pumped into the boiler. This continues until the water in the boiler heats up until the boiler temperature sensor is triggered. The sensor turns off the pump, water circulation in the heating circuit stops and the DHW mode of the boiler is switched off.

Hot water to the water taps comes from the top of the boiler through a separate pipe. This solution makes it possible by simple means to stabilize the temperature of the water that goes to the consumer. When hot water from the boiler is consumed, it is replaced by cold water from the water supply.

The water circulation rate in the DHW circuit of the boiler is selected so that the water in the boiler has time to heat up to the set temperature quickly enough so that consumers do not experience discomfort. To do this, it is convenient to install a pump that allows you to switch the operating speed.

Connecting a boiler to a double-circuit gas boiler

The Galmet SG (S) Fusion 100 L stratified heating boiler (for double-circuit boilers) has a built-in three-speed circulation pump. Boiler height 90 cm., diameter 60 cm.

You can find it on sale Layered heating boilers specially designed for connection to a double-circuit boiler. For example, the figure shows a diagram of connecting a boiler made in Poland to a boiler.

Thanks to the technology of layer-by-layer heating of water with the accumulation of hot water in the boiler, the number of boiler starts is reduced, which extends its service life and reduces gas consumption.

Uniform water temperature (without sudden changes) ensures comfortable use of water at more than one tap point.

The boiler has five pipes for connecting external pipelines. Moreover, the ends of the pipes inside the boiler are at different heights. Such a large number and arrangement of pipes allows the boiler to serve as a hydraulic separator. This solution eliminates the mutual influence on the circulation mode and water temperature in different circuits of the system and makes it easier and cheaper to connect equipment with fittings.

For example, two pipes are intended for the hot water recirculation circuit in the distribution pipes around the house. The waiting time for hot water will not depend on the length of the pipes to the water collection point. The DHW heating circuit of the boiler is connected to the other two pipes. For cold water from the water supply there is also a separate pipe.

An expansion tank and a safety valve are connected to the cold water supply pipe from the water supply system, and a check valve is also installed (not shown in the diagram).

A floor-standing boiler is also good because dirt and sludge settles and accumulates at the bottom, does not get into the pipes and does not affect the operation of the equipment.

How to make a stratified heating boiler from an electric boiler

Continued: go to

A heating boiler is a device that uses the combustion of fuel (or electricity) to heat the coolant.

Device (design) of a heating boiler: heat exchanger, heat-insulated housing, hydraulic unit, as well as safety elements and automation for control and monitoring. Gas and diesel boilers have a burner in their design, while solid fuel boilers have a firebox for wood or coal. Such boilers require a chimney connection to remove combustion products. Electric boilers are equipped with heating elements and do not have burners or a chimney. Many modern boilers are equipped with built-in pumps for forced circulation water.

Operating principle of a heating boiler- the coolant, passing through the heat exchanger, heats up and then circulates through the heating system, releasing the resulting thermal energy through radiators, heated floors, heated towel rails, and also providing water heating in an indirect heating boiler (if it is connected to the boiler).

A heat exchanger is a metal container in which the coolant (water or antifreeze) is heated - can be made of steel, cast iron, copper, etc. Cast iron heat exchangers are resistant to corrosion and quite durable, but are sensitive to sudden temperature changes and are heavy. Steel ones can suffer from rust, so their internal surfaces are protected with various anti-corrosion coatings to increase their service life. Such heat exchangers are the most common in the production of boilers. Copper heat exchangers are not susceptible to corrosion, and due to their high heat transfer coefficient, low weight and dimensions, such heat exchangers are popular and are often used in wall-mounted boilers, but are usually more expensive than steel ones.
In addition to the heat exchanger, an important part of gas or liquid fuel boilers is the burner, which can be various types: atmospheric or fan, single-stage or two-stage, with smooth modulation, double. (A detailed description of the burners is presented in articles about gas and liquid fuel boilers).

To control the boiler, automation is used with various settings and functions (for example, a weather-dependent control system), as well as devices for remote control of the boiler - a GSM module (regulating the operation of the device via SMS messages).

Main technical characteristics heating boilers are: boiler power, type of energy carrier, number of heating circuits, type of combustion chamber, type of burner, type of installation, presence of a pump, expansion tank, boiler automation, etc.

To determine required power For a heating boiler for a house or apartment, a simple formula is used - 1 kW of boiler power to heat 10 m 2 of a well-insulated room with a ceiling height of up to 3 m. Accordingly, if heating is required for a basement, a glassed-in winter garden, rooms with non-standard ceilings, etc. The boiler power must be increased. It is also necessary to increase the power (about 20-50%) when providing a boiler and hot water supply (especially if it is necessary to heat the water in the pool).

Let us note a feature of calculating power for gas boilers: the nominal gas pressure at which the boiler operates at 100% of the power declared by the manufacturer, for most boilers is from 13 to 20 mbar, and the actual pressure in gas networks in Russia can be 10 mbar, and sometimes below. Accordingly, a gas boiler often operates at only 2/3 of its capacity and this must be taken into account when calculating. When choosing the boiler power, be sure to note all the features of the thermal insulation of the house and premises. For more details, see the table for calculating the power of a heating boiler.

So which boiler is better to choose? Let's look at the types of boilers:

"Middle class"- average price, not so prestigious, but quite reliable, standard standard solutions are presented. These are Italian boilers Ariston, Hermann and Baxi, Swedish Electrolux, German Unitherm and boilers from Slovakia Protherm.

"Economy class" - budget options, simple models, service life is shorter than that of boilers of a higher category. Some manufacturers have budget boiler models, for example,

If it is possible to connect main gas to the house, then an automated gas boiler will be used to prepare hot water and heat the house. Today, this is a self-evident solution due to the low cost of natural gas and the ease of use of the boiler.

The choice is not difficult, but...

There are usually no problems with choosing a gas boiler. It is known that a wall-mounted boiler with a burner closed type, in which a short chimney exits through the wall, most preferable for low heating capacities - up to 30 kW.

With the boiler power, everything is also clear - it is selected according to known criteria or according to the recommendations of specialists.

But the difficulty is mainly caused by the question of whether to choose a single-circuit or double-circuit boiler. And also whether an indirect heating boiler is needed or not - after all, this is a significant additional expense. And if you buy a boiler, then how to connect it to the boiler.

Features of each boiler

In a single-circuit boiler, the liquid can be heated in only one heat exchanger to heat the house. There is no heat exchanger for water supply, and the boiler has two hydraulic connections - supply and return for heating.

In a double-circuit boiler, heating fluid and water for hot water supply (DHW) can be heated.

In order to obtain hot water for domestic needs with a single-circuit boiler, you need to connect an indirect heating boiler to it. This is a large container in a heat insulator, inside of which there is a coil for the passage of coolant from the heating system.

The DHW boiler is connected to the heating circuit according to a special scheme. Which, as a rule, provides the so-called “Boiler Priority”. If the water in the DHW system has cooled below the set value, the boiler switches completely to heating the boiler. When the water has warmed up, usually to 50 - 55 degrees, the heating is turned on again.

Additional equipment for connecting the boiler

Additional equipment is installed with the boiler:

• An expansion tank in a domestic hot water system is a device that compensates for the increase in water volume when heated. Capacity – 1/10 of the boiler volume.
• A circulation pump that will provide hot water supply and pressure in the DHW system.
• Safety valve, as well as additional pipelines, taps and other system elements.

You also need to remember that installing all this yourself is not so easy if you haven’t “turned the nuts” before. You'll have to invite a specialist.

It is unlikely that it will be possible to place a boiler with a boiler and other elements of the system in the kitchen. And it’s not rational because of the clutter and noise of the equipment. Therefore, it is advisable to allocate a separate room for it - a boiler room.

Features and disadvantages of a double-circuit boiler

A double-circuit boiler is a mini-boiler room in “one cabinet”; it already contains safety devices and circulation pumps, and
some models and expansion tanks. And all this fits in a small device hanging on the wall.

The performance of direct water heating in the circuit is not high - it is calculated only for one open tap. This means that only one person can take a shower and it is advisable that he is not disturbed at this time by opening a hot tap in the kitchen, and the bathroom should not be too large, since it takes a long time to fill it with high-temperature water.

Each time the tap is opened, the second circuit of the boiler will be switched on if the water heating mode is set. Frequent switching on of the boiler often simply worries the owners - will it break down prematurely?

Placement of dual circuit

The main purpose of double-circuit boilers is small houses and apartments where the equipment is located near the kitchen, but not far from the bathroom. Short distances are a necessity for this type of boiler; the shorter the path of hot water to the consumer, the better, so that you don’t have to wait too long for hot water to flow.

Experts believe that the maximum distance from the heating circuit to the tap is 7 meters. Anything more and it all just becomes wasteful. The usual distances are from 1.5 to 3 meters. But the priority placement is the kitchen, where the hot tap opens frequently.

When do you need a boiler?

For a large house, where there are significant distances between hot water consumers, and also where there is a high consumption of hot water, or where people want to consume a lot of hot water, you need to choose an indirect heating boiler - it can instantly produce an “avalanche” of heated liquid without significant temperature changes.

You can also make a system of constant circulation of hot water between the tap and the boiler, and if you open the tap even 20 meters from the boiler, you will immediately get hot water.

This is much more economical than waiting a couple of minutes, flushing tons of cold water. In such conditions with a double-circuit boiler, the lack of power in the second circuit will already cause significant inconvenience.

Boiler volume

Typically, boilers with a volume of 80 to 300 liters are installed. The volume of the boiler, in principle, is not very limited by the power of the boiler and is selected according to preference. The greater the number of baths, the larger the boiler needed. Let's just say that for a large bathtub with hydromassage, even 300 liters is not enough - you need 500.

In most cases, the choice is limited to sizes of 100 - 200 liters.
The same volume will very quickly heat up a conventional gas boiler with a capacity of 12 - 20 kW.

Question of price

A double-circuit boiler is only slightly more expensive than a single-circuit boiler. But the kit - a single-circuit boiler, plus a boiler, plus the entire system for the boiler - is quite significant in price - several hundred dollars more expensive than a double-circuit boiler.

Another factor pushing you to make the same choice is the lack of information. People often don’t know why else they need an expensive boiler element and all the complications associated with it, and they don’t want to understand it. And this often leads to the following result.

How not to connect a hot water boiler

This situation often happens. Feeling the lack of comfort in using hot water from a double-circuit boiler, residents decide to rectify the situation and buy a boiler. But how to connect it?

The answer would seem obvious - without additional automation, cheaply, directly to the second free circuit of the boiler.

But this cannot be done. The second circuit is limited in temperature to 60 degrees, so that there are no burns from the hot water supply. Therefore, it will never heat the water in the boiler to 60 degrees, even to 50. When heated, the temperature at the return of this circuit will rise to 50 degrees, and the boiler will operate in an abnormal mode, with a minimum flame, constantly turning off and on, etc. Therefore, it remains to connect the boiler, as it should be according to the classical scheme, to a high-temperature heating circuit.

Boilers with built-in hot water boiler

These are floor-standing devices that resemble a refrigerator in appearance, but can be low-power, i.e. These are adapted samples of wall-mounted boilers. With a boiler capacity of up to 100 liters, they can also be wall-mounted.

The peculiarity is that boilers combined with a boiler can be installed as a separate unit not only in the boiler room, but also in another utility room - a convenient thing when there is a lack of space, and there is no need to mount the system together.
It is not recommended to install any boilers in places where people are constantly present, as they make noise. Installation in the kitchen is rather a necessary measure.

As a result, we figured out when it is worth buying a double-circuit boiler, and when you need a single-circuit one. But in principle, there is an opinion that there is no need to save on the hot water supply system. It should be as comfortable as possible. Therefore, a boiler with a single-circuit boiler is still a priority.

The hot water supply system in your home can be organized in different ways. Fortunately, manufacturers today offer various options. The easiest way is to install a hot water gas boiler, which will heat water in its tank to the required temperature. True, this is not the most economical option, so there are better ways. For example, you can install a gas boiler with a boiler. What is it and how does it all work?

The lineup

Let's start with the fact that there are two models that work using the same technology, but the boiler itself is located differently:

• Models with a free-standing boiler.
• With built-in reservoir.

First option

For this, a separate gas boiler and a separate boiler are purchased. Here it is very important to accurately correlate the boiler power with the volume of the container. It may happen that the performance of a gas boiler is not enough to heat the water inside the boiler to a certain temperature (often up to +60°C) in a short period of time. This means you will not receive either hot water or an efficient heating system. Why?

It's all about the principle of operation of wall-mounted or floor-standing gas boilers with a boiler. It turns out that the coolant, heating up inside the boiler, is redistributed as needed. If the temperature of water for household needs inside the boiler corresponds to the programmed indicator, then the coolant works for the heating system. As soon as the temperature becomes lower, it is immediately redistributed to the DHW system. That is, the supply of coolant to the heating system is immediately turned off. This means the temperature in the house becomes lower.

Floor-standing with boiler

Attention! The larger the boiler volume you choose, the higher the likelihood that when the coolant is redistributed, the temperature in the house will always be lower than necessary. That is why we already said above that it is necessary to accurately correlate two indicators: the power of the heating unit and the volume of the boiler.

Currently, manufacturers offer two options for this type of boiler:

1. Single-circuit with a separate hot water tank.
2. Dual-circuit.

In the first case, these are floor-standing gas boilers with high power. In the second - these are wall structures. And here the question arises, which one to choose? It all depends on how much area you have to heat. If it's an apartment or small Vacation home(dacha), then the second option. If it's big a private house, then only the first one. But keep in mind that each type has its own advantages and disadvantages.

With built-in boiler

For example, a double-circuit gas boiler with a boiler has a heat exchanger with a small cross-section, that is, with a small cross-section. This is a minus. In addition, salt and mud deposits quickly settle in them, which means they will have to be washed and purged more often. In addition, maintenance of a single-circuit boiler and the boiler itself is simpler; in fact, the consumer receives a kind of central network through which the coolant flows, used for both heating and domestic hot water.

Second option

Gas boilers with a built-in boiler are double-circuit wall-mounted models, where part of the thermal energy is spent on heating water inside the tank, which is built into the body of the boiler itself. So to speak:

• The built-in tank complicates and enlarges the design.
• The tank volume is not very large. There is both a plus and a minus here. Plus - quick heating of a small amount of water located in the boiler, and, therefore, a reduction in heat costs. The downside is a small amount of hot water, which may last for a few minutes.
• Typically, double-circuit wall-mounted units are equipped with a complex automation system. There are pros and cons here too. Pros - boilers operate efficiently and economically. Cons: the automation itself is very capricious and often breaks down.

Boiler and boiler wiring diagram

On Russian market wall-mounted gas boilers with a built-in boiler are not very popular. Our compatriots are trying to purchase units that create the least problems with their operation. Complex setup temperature regime, all kinds of switching, monitoring pressure and temperature - all this annoys us. Therefore, Russians choose more simplified designs. And here a boiler (wall-mounted or floor-mounted) with a separate boiler is the optimal solution.

Other options

We talked above about storage-type structures. That is, the water in the tank has a certain volume, which heats up. But there are also flow-type models on the market. In them, water is heated to a certain temperature as it moves through a special heat exchanger.

Typically, the heat exchanger is made of a material with high thermal conductivity and good corrosion resistance. Therefore, this unit is most often made of copper, aluminum or stainless steel. But their shape is coiled, because you have to install a heat exchanger of quite a long length in a small volume. And the longer it is, the more efficiently it heats the water. By the way, water heating gas boilers, which were already mentioned above, operate using this system.

Simple connection diagram

Advantages of single-circuit boilers with a boiler

So, we have established that single-circuit gas boilers with a separate boiler are considered the most popular today. Therefore, there is a need to outline all its advantages:

• Large internal cross-section of the heat exchanger. This helps reduce scale formation. Unfortunately, the quality of water used in domestic water supply systems leaves much to be desired.
• High reliability indicator, which is determined by the simplicity of the design of the device itself.
• In this model, the consumption of thermal energy is more rational, and, therefore, this is the reason for the high efficiency and savings in fuel consumption.
• The water inside the boiler almost always has a certain temperature. It is not affected by pressure surges inside the gas line or temperature surges inside the heating system of the house.
• Ease of maintenance, where it is necessary to note a minimum of automation devices.
• The entire set (gas boiler plus boiler) consistently provides hot water to your home, regardless of the time of day. In addition, the heating also works stably.
• Simple built-in automation will help you set the necessary parameters for hot water in the DHW system and coolant in the heating system. She also controls these parameters.

Boilers

Conclusion

So, let's summarize. Nowadays, it is not difficult to organize a hot water supply system in your home. The main thing is to choose the type and method of organization wisely. As you can see, there are several options. Which one is right for you is up to you to decide. Our task is to consider the options offered by the modern market and give recommendations regarding one or another method.

Gas boiler with boiler - selection criteria

To choose the right gas boiler with a boiler, you need to understand all the designs that are offered today by leading boiler manufacturers

Gas boiler with boiler, frequently asked questions, reviews

People who do not have enough space in their apartment or house to equip a boiler room often try to save space and purchase a double-circuit boiler. This is a smart choice, however, in order to provide your family with hot liquid for the bath and everyday life, you should take care of the availability of additional equipment. Choosing a suitable tank is not difficult; you can take a tank or other container. However, to make the task easier, you can simply buy a special gas boiler with a boiler.

Possibility of connecting a boiler

A boiler for a gas boiler is a storage tank, inside of which a heat exchanger is located. This model is essentially a dual-circuit model, as it has connections for both the heating system and the hot water supply.

Double-circuit models have a built-in instantaneous water heater, which single-circuit models cannot boast of. The advantage of a gas boiler with a built-in storage tank is that there is no need to create an indirect heating boiler. In addition, the water is heated much faster than in single-circuit options and does not reduce the efficiency of the heating fluid.

A separate boiler can also be connected to double-circuit boilers to provide more hot water. Such equipment belongs to the layer-by-layer heating technique. You can also buy a double-circuit gas boiler with a built-in indirect heating boiler. Such devices are combined with the boiler, although separate devices can be purchased. Depending on what is best for you: ease of transportation and installation or compact placement, you can choose a separate or adjacent model.

If a single-circuit boiler is already installed, you can purchase a special layer-by-layer heating boiler for it, which is equipped with a flow-through liquid heater. If you need to save space in your apartment, you can opt for a single-circuit boiler with a built-in indirect heating boiler.

Heater power

Depending on the power of the gas burner, the liquid flow rate in the instantaneous water heater varies. Also, the rate of water heating depends on design features heat exchanger. A feature of heating the liquid is its short contact with the heat exchanger, so in order to warm the coolant to the desired temperature, a lot of heat is needed. To increase the performance of the heating element, you need to increase the burner power and increase the gas flow.

In order for the water temperature in the shower to be 40 degrees, you will have to set the burner to produce a power of 20 kW, but if the burner is not designed for such power, then it is impossible to take a warm shower. For a bath, you also need to have a powerful burner, since the water must heat up quickly in large volumes for a normal set.

Most boilers have a power of about 20–30 kW, and 10 kW is enough to heat a house. Thus, the entire difference can be used to provide domestic hot water. For hot water boilers, modulating burners have been developed that cover a range from 30 to 100 percent of maximum power.

However, even the weakest boilers have excess power, which leads to frequent turning on and off of the burner. This process leads to rapid wear of equipment and increases fuel consumption. These problems make purchasing a more powerful boiler model to provide more hot liquid an unprofitable and unjustified solution.

That is why double-circuit models have a boiler that holds hot water, which allows it to be released in large volumes while taking a shower or bath. Thus, layer-by-layer heating of water is optimal: it ensures normal operation of the equipment and does not lead to burner wear.

Features of layer-by-layer heating of liquid

In double-circuit models with layer-by-layer heating, water is heated using a plate radiator or tubular water heater. The presence of an additional heat exchanger is beneficial in condensing models, as it provides additional heat from combustion products. The liquid enters the boiler with layer-by-layer heating already heated, which allows you to quickly prepare hot liquid in the required volume.

Floor-standing double-circuit gas heating boilers with a boiler have a number of advantages.

1. The flow of hot water into the upper layers of the boiler allows you to take a shower 5 minutes after turning on the heat exchanger. In contrast, boilers with an indirect heating boiler provide longer heating of the liquid, since time is spent convecting warm water from below the heat source.
2. The absence of a heat exchanger inside the storage tank allows you to collect more warm water for domestic needs. The performance of such boilers is 1.5 times higher than in models with indirect heating.

FAQ

Most often, people do not understand why there is also a boiler in the boiler. The fact is that the built-in model allows for comfortable use of warm water. This allows you to quickly ensure the availability of hot liquid when opening several water intake points, something that a conventional double-circuit boiler could never cope with.

Moreover, there are cases when a small pressure of warm water is needed, which a boiler with an instantaneous water heater is not capable of, since it has a limited lower pressure limit.

Floor-standing models with a built-in storage tank are similar to a refrigerator. They hold up to 100 liters of liquid, which is enough to provide warm water for an entire family.

The connection diagram for a double-circuit gas boiler with a boiler is practically no different from standard connection. An important difference is the need to connect not only to the heating system, but also to the water supply. It is necessary to cut into the system before the water exit points, but after the toilet. This will ensure the release of hot liquid from all water intake taps. It is best to consult with specialists to connect everything correctly.

A special gas boiler with a built-in boiler has positive reviews, since its simplicity and convenience allow you to save as much space in the house as possible and at the same time solve the problem of hot water. What people say.

Veniamin, Nizhny Novgorod

I bought myself a boiler in which the boiler heats the water layer by layer. On the one hand, this made it possible to take a shower ten minutes after turning it on, but now the problem is different: a girl appeared, and the water consumption increased five times! My boiler can't cope required quantity heating the liquid, and I constantly get cold water. Now I’m thinking: change the model to a more powerful option or buy a gas water heater type heater? In general, before buying a boiler with a boiler, it is better to calculate the required volume of hot water with a reserve.

My husband bought a cool double-circuit boiler with a built-in boiler, and we are happy with this purchase. We have a family of four (me, my husband and two children), so the water consumption is considerable. The advantage of such a boiler is that it fully provides us with the necessary amount of warm liquid for showering and household needs. Moreover, the boiler itself is compact, its dimensions are no larger than those of standard models, but it replaces both the boiler and the heating device. As a result, we saved space in the bathroom. Beautiful appearance allows the boiler to become a designer element of the kitchen. Such built-in equipment looks great and does not disappoint in terms of functionality!

Not long ago I installed a double-circuit floor-standing boiler with a built-in boiler in my house; before that I had a wall-mounted gas boiler with a boiler installed. The new version is larger than the wall-mounted versions, but it also has a larger boiler volume. Having a instantaneous water heater is simply a masterpiece in this technique! Due to it, the water heats up quickly, which allows you to calmly take a shower, wash dishes or just wash your face. There is enough warm liquid for all occasions in life. I'm happy with the purchase and recommend it to everyone. Especially such a unit will be appropriate for small-sized rooms, where every meter is worth conquering. The water heats up quickly in the boiler, so there are no problems with waiting.

Gas boiler with boiler, frequently asked questions, reviews

Possibility of connecting a boiler, heater power. Features of layer-by-layer heating of liquid. Operation of a gas boiler with a boiler - video. Frequently asked questions and feedback

Choosing a floor-standing gas boiler with a heat accumulator boiler

The distinctive characteristic that a floor-standing gas boiler with a boiler has is the instant supply of hot water to the consumer, immediately after opening the water supply tap. The built-in storage tank has a volume from 40 to 500 liters.

The principle of operation of a floor-standing boiler with a built-in boiler

Double-circuit floor-standing gas boilers, with a built-in hot water heating boiler, differ from classic boiler equipment with two heat exchangers. The operating principle is as follows:

• Heating hot water and maintaining a constant temperature in the boiler is carried out in constant mode.

Choosing a floor-standing gas boiler with an integrated boiler

When choosing a 2-circuit boiler with an integrated storage tank-water heater, take into account the thermal characteristics and the operating principle used. According to their internal structure, the following models are distinguished:

• Atmospheric boilers have an open combustion chamber. During operation, the air from the room is burned. The installation requirements are high.

After selecting the boiler by type of operation, carry out the calculation required power and throughput.

Calculation of the required boiler power

When calculating a double-circuit unit with a built-in storage tank, two operating parameters are taken into account:

• Required power to heat the room.

The first parameter is calculated using a simple formula, 1 kW = 10 m². So, for a house of 100 m², you will need a 10 kW heating device. An additional 30% is added for DHW heating. The volume of the built-in tank varies from 40-60 liters for domestic boiler equipment, to 500 liters in industrial units.

Which brand of boiler with an internal boiler is better?

A floor-standing double-circuit gas heating boiler with an indirect heating boiler is offered by foreign manufacturers. You can make it easier to select a suitable boiler by distributing the most popular models by region:

• Germany – Bosch Condens, Vaillant ecoCOMPACT, Wolf CGS.

In order for the model you like to enjoy a long period of flawless operation, before purchasing you should pay attention to the following:

• Adaptation to domestic operating conditions - in the EU countries and the Russian Federation, different parameters of main gas pressure, water quality for hot water supply, etc.

A consultant from a company selling heating equipment will provide assistance in choosing a suitable boiler.

Floor-standing boiler with internal boiler - pros and cons

Floor-standing double-circuit gas heating boilers with an internal boiler have the following advantages:

• Fast supply of hot water to the user.

With proper installation, the boiler remains operational for the entire service life declared by the manufacturer. Installation work must be performed by a qualified and licensed professional.

Calculation of power and temperature of a warm water floor

Heating boiler power selection calculator

Calculator for calculating the number of radiator sections

Calculator for calculating the footage of a warm water floor pipe

Calculation of heat loss and boiler performance

Calculation of heating costs depending on the type of fuel

Calculator for calculating the volume of the expansion tank

Calculator for calculating heating PLEN and electric boiler

Heating costs with boiler and heat pump

Floor-standing gas boiler with storage tank for hot water supply

Easy to use, floor-standing gas boilers with a boiler provide the required amount of hot water with minimal costs fuel. The volume of the built-in storage capacity is selected according to

Gas boiler with boiler

An increasing number of consumers are striving to organize an autonomous heating system. The funds spent on the purchase and installation of heating equipment will soon pay off thanks to savings on energy resources and the ability to independently regulate the power of the system.

The optimal way to heat private houses and apartments while simultaneously obtaining hot water at any time and in the required quantity is to use a gas boiler equipped with a built-in boiler.

Design and principle of operation of a boiler with a built-in boiler

An integral part of such a heating unit is a container designed to accumulate hot water. Its volume can vary from 10 to 100 liters. A secondary heat exchanger is built inside the tank. The method of installing such a boiler largely depends on the volume of the boiler. Boilers with a capacity of up to 60 liters are usually wall-mounted, and those with a capacity of more than 60 liters are floor-mounted.

These units may have an open or closed combustion chamber. In the first case, heating equipment operates using traditional chimneys, in the second, combustion products are removed through coaxial chimneys.

Attention! The power range of boilers with a built-in boiler usually starts from 28 kW.

To get hot water, simply open the tap. While hot water is being consumed, the boiler heats up its new supply.

Advantages of heating units with built-in water storage

A gas boiler with a boiler is an ideal solution when using several water points (2-4) and provides the following advantages:

• A significant positive point is the ability to heat water even during peak hours, when the pressure in the pipeline is very weak.

Attention! In this case, double-circuit conventional boilers may simply not switch on to the water heating mode in the DHW circuit.

• To put into operation a unit with a built-in hot water storage tank, a separate installation of water supply and heating systems is not required. It is enough to connect energy carriers to the boiler - gas and electricity (for automatic operation), as well as water.
• The units are compact, so they do not require much space for their placement. All components of the equipment are assembled in a single housing.

Among boiler equipment equipped with storage tanks, units of the Beretta and Protherm brands can be distinguished.

Beretta boiler with built-in boiler

The Italian company Beretta produces all types of heating equipment. The products of this company belong to the economy class, but only high-quality materials are used for their production.

Beretta Boiler 28 BAI is a wall-mounted turbocharged boiler with a 60-liter boiler made of stainless steel. The power of the unit is 28 kW.

Features of the model that ensure its comfortable and safe operation:

• Automatic electric ignition, ionization control function of the burner flame.
• The modulating burner provides the ability to smoothly change power.
• The atmospheric burner, made of stainless steel, provides an easy transition from operating on main gas to liquefied gas.
• The boiler is equipped with a three-speed circulation pump with deaerator.
• The heating equipment is equipped with two expansion tanks. One, with a volume of 8 liters, is installed in the heating circuit, the second has a volume of two liters and is installed in the DHW circuit.
• The boiler has two modes “Winter-Summer”. In the “Winter” mode, the S.A.R.A. function is activated, which provides automatic adjustment of the coolant temperature; it is recommended to use a room temperature regulator.
• The Safety Baby function (protection against burns) provides for a water temperature in the storage tank of approximately 43 0 C without the ability to regulate it.

Advice! The Safety Baby function can only be activated by contacting the service department.

• The system protects the boiler from freezing and the pump from blocking.
• External control devices can be connected to the equipment, which include a room thermostat, programmer, and outside temperature sensor.

Attention! Connecting a programmer and an outside temperature sensor provides the function of weather-dependent control of the coolant temperature.

The control panel contains: a thermomanometer, an operating mode switch, a coolant temperature regulator in the heating circuit, a water temperature regulator in the circuit responsible for supplying hot water, and an indicator indicating the state of the boiler.

The cost of this unit is approximately $1,500.

Design features of the Protherm Bear 30 KLZ boiler

The boiler model Protherm 30 KLZ is an excellent solution for those who, along with an efficient heating system, want to have an uninterrupted supply of hot water in the required quantity. The unit is equipped with a horizontal boiler with a capacity of 90 liters.

Design features of the gas boiler Protherm 30 KLZ:

• The storage tank contains a magnesium electrode that protects the container from corrosion, and a built-in circulation pump.
• The power of the unit can be varied from 70 to 100% using a modulating burner.
• Combustion products can be removed naturally or forcibly using a turbo attachment.
• The boiler has a floor-standing design and can be adjusted in height to provide stability to the unit.
• This equipment can be controlled by a thermostat and an outside temperature sensor.
• The boiler is equipped with two expansion tanks - 4 liters for the boiler and 10 liters for the heating circuit.

Attention! The Protherm 30 KLZ unit is used for heating and supplying hot water to private housing construction, apartments, office premises, and small industrial enterprises that have running water.

The approximate cost of the unit is $2,500.

Gas boiler with boiler: design and principle of operation, advantages of models with built-in water storage, review of the Beretta Boiler 28 BAI and Protherm Medved 30 KLZ boilers, “All about heating boilers”

The optimal way to heat private houses and apartments while simultaneously obtaining hot water at any time and in the required quantity is to use a gas boiler equipped with a built-in boiler.