When developing a heating system for our home, we certainly think about the layout of pipes and connecting radiators. Most often, when creating projects, common schemes with two pipes laid through heated rooms are used. A two-pipe heating system is more difficult to install, but it has many undeniable advantages– this is exactly what we will talk about in our review. We will also look at:

• Structural features of two-pipe heating systems;
• Their main disadvantages are;
• Varieties of two-pipe systems.

At the very end we will talk about the most effective ways connecting batteries to heating systems.

Features of two-pipe heating systems

A two-pipe heating system is the most common installation scheme heating pipes and connecting radiators. It involves the use of two pipes - one supplies hot coolant, and the second carries it to the heating boiler. This scheme is different high efficiency and ensures uniform heat distribution throughout all heated rooms.

Single-pipe heating systems, unlike two-pipe ones, have a number of disadvantages:

The difference in the operation of one-pipe and two-pipe heating systems is well illustrated by this picture.

• More limited contour length;
• Uneven distribution of heat throughout heated rooms - the very last rooms suffer;
• It is difficult to heat multi-story buildings;
• Increased hydrodynamic resistance in the heating system;
• Lack of separate adjustment of heating temperature in different rooms;
• Difficulties in repair - it is impossible to remove a faulty battery without stopping the entire system.

Some of the above-mentioned problems are partially solved with the help of the “Leningradka” scheme, but this is not a complete solution to the situation.

A two-pipe heating system involves laying two parallel pipes to which radiators are connected. The coolant from the supply pipe enters the heating devices, after which it is sent to return pipe(return). Despite the more impressive financial and labor costs, the finished system is more functional to operate and easier to repair.

Two-pipe heating is actively used to heat rooms and buildings for various purposes. These include one-story private houses and cottages, multi-story apartment buildings, as well as industrial and administrative buildings. In other words, the scope of its application is distinguished by its breadth.

Advantages and disadvantages of two-pipe heating systems

Two-pipe heating is distinguished by its versatility. It works equally well in both small buildings, and in multi-storey buildings, including high-rise residential buildings. Let's look at the main advantages of two-pipe systems:

When using two-pipe heating, even the most distant radiators in the house will be able to provide heat at an acceptable level.

• Increased length of one line (circuit) - this is important when heating elongated buildings, for example, hospital or hotel buildings;
• Uniform supply of heat to the rooms - unlike single-pipe systems, there will be heat even in the rooms furthest from the boiler;
• Two-pipe heating makes it easy to organize separate temperature control in separate rooms and spaces - for this, thermostatic heads are installed on each radiator;
• The ability to dismantle radiators and convectors without stopping the entire heating system is an important advantage that manifests itself in large buildings;
• Two-pipe heating is ideally suited for heating large buildings - for more uniform heat distribution, certain pipe routing and connection schemes are used heating devices.

Unfortunately, it was not without certain disadvantages:

• High costs for purchasing equipment - compared to single-pipe heating systems, double-pipe heating systems require an increased number of pipes;
• Difficulty in installation - due to an increase in the number of units and the need for optimal distribution of coolant throughout the heated rooms.

Nevertheless, the advantages completely outweigh the above disadvantages.

Types of two-pipe heating systems

We have already become familiar with the advantages and disadvantages of two-pipe heating systems, as well as their distinctive features. It remains to talk about their varieties.

Forced or natural circulation

Natural circulation of the coolant involves the absence of a circulation pump. Heated water circulates through the pipes independently, obeying the forces of gravity. True, this requires pipes of increased diameter - two-pipe heating with thin plastic pipes will not be able to ensure independent circulation, which is associated with high hydrostatic pressure in the system. Heating with natural circulation is simple and cheap, but you must remember the limited length of the circuit - it is not recommended to make it longer than 30 meters.

The scheme of a two-pipe heating system with forced circulation involves the use of a circulation pump. It is installed next to the heating boiler and ensures rapid passage of coolant through the pipes. Thanks to this, the warm-up time is reduced, the length of the heating circuit is increased, and the distribution of thermal energy is noticeably improved. The two-pipe heating system with forced circulation allows you to heat buildings of any number of floors - you just need to select a high-performance pump.

Disadvantages of two-pipe heating systems with circulation pumps:

• Increased cost of installation - good pump it is expensive, while buying a cheap one does not make sense due to its reduced service life;
• Possible noise - cheap pumps sooner or later begin to vibrate, the sounds from their operation travel through the pipes even to the farthest rooms. The higher the rotation speed of the pump shaft, the louder the noise;
• The energy dependence of the heating system - when the power is turned off, the circulation of the coolant stops.

For the correct operation of a two-pipe heating system with a circulation pump, it is necessary to provide a backup power source, otherwise the heating boiler may break down.

It should be noted that cheap circulation pumps are noisy even at the very beginning of operation. Increased noise levels are most noticeable in heating systems with metal pipes. And if any section of the pipe gets into resonance, the sound will only intensify.

You should also pay attention to the method of laying pipes - in two-pipe heating systems with natural circulation, a slope is provided, which ensures normal movement of the coolant. In circuits with forced circulation, no slopes are needed. For the same reason, pipes can be bent as many times as desired, avoiding obstacles - in circuits with natural coolant movement, pipes should be as straight as possible so as not to create excessive hydrodynamic resistance.

Open and closed circuits

Two-pipe heating scheme open type involves the use of a traditional expansion tank, which is mounted at the highest point of the circuit. The pressure here is minimal, the coolant is in contact with the atmosphere. In case of excessive expansion, the water goes into a special pipe extending from the tank. An undoubted advantage of open circuits is the ease of air removal - it exits through the expansion tank on its own. Only, along with the air leaving, the coolant evaporates, so its level must be constantly monitored.

If there is insufficient water in open two-pipe heating systems, gurgling of water can be heard in the radiators.

Closed heating systems include sealed membrane-type expansion tanks. The coolant here circulates in a confined space, so there is nowhere for it to evaporate. If necessary, you can add non-freezing ethylene glycol here. In order to prevent airing of the circuit, air vents are installed in it - automatic or manual.

IN closed systems In heating systems, a circulation pump must be installed, while in open ones its presence is not mandatory.

Vertical and horizontal two-pipe heating systems

A two-pipe horizontal heating system is relevant in one-story houses. Two pipes are laid throughout the premises, parallel to which radiators are connected. If a household or building includes 2-3 floors, then a separate horizontal circuit is created on each floor, connected to vertical risers. This connection scheme ensures uniform distribution of the coolant across all floors and rooms.

Vertical systems are most often installed in apartment buildings. Two vertical pipes are installed here from the top to the bottom floor. Hot coolant is supplied through one, and through the other it descends back to the boiler room. Radiators are connected to both pipes. Most often, the scheme looks like this: separate risers serve all radiators in kitchens, others - in bedrooms, halls and other rooms.

Mixed systems are also installed in buildings, which include both vertical and horizontal sections.

Upper and lower wiring

There are two-pipe heating systems with upper and lower pipe distribution. Top wiring means that the coolant first rises to the very top point contour, and from there it is distributed into separate vertical sections. Two-pipe heating with bottom wiring provides that both pipes pass below (near the floor or under it), and branches extend from them upward, to radiators and separate cascades of radiators.

The upper wiring is aimed at creating two-pipe heating systems with independent movement of the coolant. The pipe from the boiler rises to the top point of the system, where the horizontal section begins - it is made at an angle. A similar slope is made in the return pipe so that the coolant flows independently towards the boiler, obeying the pressure in the circuit and gravity.

The second scheme (bottom) is optimal where you need to hide all the pipes. In this case, a two-pipe heating system with bottom wiring made of polypropylene is hidden in the floors or behind the ceilings; only radiators and convectors are visible in the rooms.

Connecting radiators

We introduced you to the main types of two-pipe heating systems. Now you know that the coolant here is supplied through one pipe and removed through another. This ensures even heat distribution even in the largest buildings. Let's see how we can best connect heating batteries. There are three possible connection schemes:

• Lateral connection - supply and return pipes approach the heating device from the side. Accordingly, areas located only on one edge will be the warmest;
• Bottom connection - supply and return pipes fit to the lower edges of radiators and convectors. Heat losses in such a scheme will be maximum, since the coolant tends to pass through the internal volume “right through”, along the straightest section;
• Diagonal is the most optimal scheme connection, ensuring uniform heat distribution throughout the internal volume of the radiators. For example, the inlet pipe goes to the upper left entrance, and the outlet pipe goes to the lower right (or vice versa). In this case, the coolant will heat the entire area of ​​the heating devices as evenly as possible.

The choice of a suitable scheme depends on the design of the heating system and the number of sections in the radiators. When creating two-pipe heating, we recommend choosing a diagonal and lateral connection.

Video

A two-pipe heating system is more complex than a single-pipe one, and the amount of materials required for installation is significantly greater. Nevertheless, it is the 2-pipe heating system that is more popular. As the name suggests, it uses two circuits. One serves to deliver hot coolant to the radiators, and the second takes the cooled coolant back. Such a device is applicable to any type of structure, as long as its layout allows for the installation of this structure.

The demand for a double-circuit heating system is explained by the presence a number of significant advantages. First of all, it is preferable to a single-circuit one, since in the latter the coolant loses a noticeable part of the heat even before it enters the radiators. In addition, the double-circuit design is more versatile and suitable for houses of different floors.

Disadvantage of a two-pipe system its price is considered high. However, many people mistakenly believe that the presence of 2 circuits requires the use of twice the number of pipes, and the cost of such a system is twice as much as a single-pipe system. The fact is that for a single-pipe design it is necessary to take pipes of large diameter. This ensures normal coolant circulation in the pipeline, and therefore effective work such a design. The advantage of a two-pipe system is that for its installation, pipes of smaller diameter are used, which are significantly cheaper. Accordingly additional elements(pipes, valves, etc.) are also used with a smaller diameter, which also somewhat reduces the cost of the design.

The installation budget for a two-pipe system will not be much larger than for a single-pipe system. On the other hand, the efficiency of the first will be noticeably higher, which will be a good compensation.

Application example

One of the places where two-pipe heating would be very practical is garage. This workroom, so constant heating is not required here. In addition, a two-pipe heating system with your own hands is a very real idea. Installing such a system in a garage is not necessary, but it will be absolutely useful, since winter time It’s very difficult to work here: the engine won’t start, the oil freezes, and it’s just uncomfortable to work with your hands. Two-pipe heating system provides completely acceptable conditions for staying indoors.

Types of two-pipe heating systems

There are several criteria by which such heating structures can be classified.

Open and closed

Closed systems assume the use of an expansion tank with a membrane. They can work with high blood pressure. Instead of ordinary water in closed systems, you can use coolants based on ethylene glycol, which do not freeze at low temperatures(up to 40 °C below zero). Motorists know such liquids as “antifreeze”.

1. Heating boiler; 2. Security group; 3. Relief valve overpressure; 4. Radiator; 5. Return pipe; 6. Expansion tank; 7. Valve; 8. Drain valve; 9. Circulation pump; 10. Pressure gauge; 11. Make-up valve.

However, we must remember that for heating devices there are special compositions of coolants, as well as special additives and additives. The use of ordinary substances can lead to breakdown of expensive heating boilers. Such cases may be regarded as non-warranty, and therefore repairs will require significant costs.

Open system characterized by the fact that expansion tank must be installed strictly at the highest point of the device. It must be equipped with an air connection and a drainage pipeline through which it is drained. excess water from the system. You can also take it through warm water For economic needs. However, such use of the tank requires automatic replenishment of the structure and eliminates the possibility of using additives and additives.

1. Heating boiler; 2. Circulation pump; 3. Heating devices; 4. Differential valve; 5. Gate valves; 6. Expansion tank.

And yet the two-pipe heating system closed type considered safer, therefore modern boilers are most often designed for it.

Horizontal and vertical

These types differ in the location of the main pipeline. It serves to connect all structural elements. Both horizontal and vertical systems have their own advantages and disadvantages. However, both of them demonstrate good heat transfer and hydraulic stability.

Two-pipe horizontal heating design found in one-story buildings, and vertical- in high-rise buildings. It is more complex and, accordingly, more expensive. Here vertical risers are used, to which heating elements are connected on each floor. Advantage vertical systems is that, as a rule, air jams do not occur in them, since the air flows through the pipes up to the expansion tank.

Systems with forced and natural circulation

These types differ in that, firstly, there is an electric pump that forces the coolant to move, and secondly, circulation occurs on its own, obeying physical laws. The disadvantage of pump designs is that they depend on the availability of electricity. For small rooms special meaning in coercive systems no, except that the house will heat up faster. For large areas, such designs will be justified.

To choose the right type of circulation, it is necessary to consider which type of pipe layout used: upper or lower.

Top wiring system involves laying a main pipeline under the ceiling of the building. This provides high pressure coolant, due to which it passes well through the radiators, which means that the use of a pump will be unnecessary. Such devices look more aesthetically pleasing; the pipes at the top can be hidden decorative elements. However, a membrane tank must be installed in this system, which entails additional expenses. It is possible to install an open tank, but it must be at the highest point of the system, that is, in the attic. In this case, the tank must be insulated.

Bottom wiring involves installing the pipeline just below the window sill. In this case, you can install an open expansion tank anywhere in the room slightly above the pipe and radiators. But such a design cannot be done without a pump. In addition, difficulties arise if the pipe must pass past the doorway. Then it is necessary to run it around the perimeter of the door or make 2 separate wings in the contour of the structure.

Dead end and passing

In a dead-end system Hot and cooled coolant flow in different directions. IN passing system , designed according to the Tichelman scheme (loop), both flows go in the same direction. The difference between these types is the ease of balancing. If the associated flow, when using radiators with an equal number of sections, is itself already balanced, then in the dead-end section a thermostatic valve or needle valve must be installed on each radiator.

If the Tichelman scheme uses radiators with an unequal number of sections, the installation of valves or taps is also required here. But even in this case, this design is easier to balance. This is especially noticeable in extended heating systems.

Selection of pipes by diameter

The choice of pipe cross-section must be made based on the volume of coolant that must pass per unit of time. It, in turn, depends on the thermal power required to heat the room.

In our calculations, we will proceed from the fact that the amount of heat loss is known and there is a numerical value of the heat required for heating.

Calculations begin with the final, that is, the farthest radiator of the system. To calculate the coolant flow for a room, you will need the formula:

G=3600×Q/(c×Δt), Where:

• G – water consumption for heating the room (kg/h);
• Q − thermal power, required for heating (kW);
• c – heat capacity of water (4.187 kJ/kg×°C);
• Δt is the temperature difference between the hot and cooled coolant, taken equal to 20 °C.

For example, it is known that the thermal power for heating a room is 3 kW. Then the water consumption will be:
3600×3/(4.187×20)=129 kg/h, that is, about 0.127 cubic meters. m of water per hour.

To water heating was balanced as accurately as possible, it is necessary to determine the cross-section of the pipes. To do this we use the formula:

S=GV/(3600×v), Where:

• S is the cross-sectional area of ​​the pipe (m2);
• GV – volumetric water flow (m3/h);
• v is the speed of water movement, is in the range of 0.3−0.7 m/s.

If the system uses natural circulation, then the movement speed will be minimal - 0.3 m/s. But in the example under consideration, let’s take the average value - 0.5 m/s. Using the indicated formula, we calculate the cross-sectional area, and based on it, the internal diameter of the pipe. It will be 0.1 m. We select polypropylene pipe the nearest larger diameter. This product is with internal diameter 15 mm.

Then we move on to to the next room, we calculate the coolant flow rate for it, sum it up with the flow rate for the calculated room and determine the diameter of the pipe. And so on all the way to the boiler.

System installation

When installing the structure, certain rules should be followed:

• any two-pipe system includes 2 circuits: the upper one serves to supply hot coolant to the radiators, the lower one to remove cooled fluid;
• the pipeline should have a slight slope towards the final radiator;
• the pipes of both circuits must be parallel;
• the central riser must be insulated to prevent heat losses when supplying coolant;
• in reversible two-pipe systems, it is necessary to provide several taps with which it is possible to drain water from the device. This may be needed during repair work;
• when designing a pipeline, it is necessary to provide for the smallest possible number of angles;
• The expansion tank must be installed in the very high place systems;
• the diameters of pipes, taps, pipes, connections must match;
• when installing a pipeline made of heavy steel pipes to support them you need to install special fasteners. Maximum distance between them is 1.2 m.

How to do correct connection heating radiators, which will ensure maximum comfortable conditions in the apartment? When installing two-pipe heating systems, you must adhere to the following sequence:

1. The central riser of the heating system is diverted from the heating boiler.
2. At the highest point, the central riser ends with an expansion tank.
3. Pipes run from it throughout the building, supplying hot coolant to the radiators.
4. To remove cooled coolant from heating radiators with a two-pipe design, a pipeline is laid parallel to the supply one. It must be connected to the bottom of the heating boiler.
5. For systems with forced circulation of coolant, an electric pump must be provided. It can be installed at any convenient point. Most often it is installed near the boiler, near the entry or exit point.

Connecting a heating radiator is not such a difficult process if you approach this issue scrupulously.

According to statistics, over 70% of all residential buildings are heated using water heating. One of its varieties is a two-pipe heating system - this publication is dedicated to it.

The article discusses the advantages and disadvantages, diagrams, drawings and recommendations for installing two-pipe wiring with your own hands.

Contents of the article

Differences between a two-pipe heating system and a single-pipe one

Any heating system is a closed circuit through which coolant circulates. However, unlike a one-pipe network, where water is supplied to all radiators in turn through the same pipe, a two-pipe system involves dividing the wiring into two lines - supply and return.

A two-pipe heating system for a private house, in comparison with a single-pipe configuration, has the following advantages:

1. Minimal coolant losses. In a single-pipe system, radiators are alternately connected to the supply line, as a result of which the coolant passing through the battery loses temperature and enters the next radiator partially cooled. With two-pipe configuration, each battery is connected to the supply pipe with a separate outlet. You get the opportunity to install on each of the radiators, which will allow you to regulate the temperature in different rooms houses independently of each other.
2. Low hydraulic losses. When installing a system with forced circulation (necessary in large buildings), a two-pipe system requires the installation of a less efficient circulation pump, which allows for significant savings.
3. Versatility. A two-pipe heating system can be used in multi-apartment, single or two-story building.
4. Maintainability. On each branch of the supply pipeline it is possible to install shut-off valves, which makes it possible to cut off the coolant supply and repair damaged pipes or radiators without stopping the entire system.

Among the disadvantages of this configuration, we note a twofold increase in the length of the pipes used, however, this does not threaten a dramatic increase in financial costs, since the diameter of the pipes and fittings used is smaller than when installing single pipe system.

Classification of two-pipe heating

The two-pipe heating system of a private house, depending on its spatial location, is classified into vertical and horizontal. The more common is the horizontal configuration, which involves connecting radiators on a building floor to a single riser, while in vertical systems radiators from different floors are connected to the riser.

The use of vertical systems is justified in a two-story building. Despite the fact that the arrangement of such a configuration is more expensive due to the need to use more pipes, with vertically located risers, the possibility of formation of air jams inside radiators, which increases the reliability of the system as a whole.

Also, a two-pipe heating system is classified according to the direction of movement of the coolant, according to which it can be direct-flow or dead-end. In dead-end systems, liquid circulates through the return and supply pipes in different directions; in direct-flow systems, their movement coincides.

Depending on the method of transporting the coolant, systems are divided into:

• with natural circulation;
• with forced circulation.

Heating with natural circulation can be used in one-story buildings with up to 150 square meters. It does not provide for the installation of additional pumps - the coolant moves due to its own density. Characteristic feature systems with natural circulation is to lay pipes at an angle to horizontal plane. Their advantage is independence from the availability of power supply, the disadvantage is the inability to adjust the water supply speed.

In a two-story building, a two-pipe heating system is always performed with forced circulation. In terms of efficiency, this configuration is more effective, since you get the opportunity to regulate the flow and speed of the coolant using a circulation pump, which is installed on the supply pipe leaving the boiler. In heating with forced circulation, pipes of relatively small diameters (up to 20 mm) are used, which are laid without a slope.

Which heating network layout to choose?

Depending on the location of the supply pipeline, two-pipe heating is classified into two types - with upper and lower wiring.

The diagram of a two-pipe heating system with overhead wiring involves installation expansion tank and the distribution line at the highest point of the heating circuit, above the radiators. This installation cannot be done in one-story building With flat roof, since to place communications you will need an insulated attic or a specially designated room on the second floor of a two-story house.

A two-pipe heating system with bottom wiring differs from the top one in that the distribution pipeline in it is located in the basement or in an underground niche, under the radiators. The outermost heating circuit is the return pipe, which is installed 20-30 cm lower than the supply line.

It's more complex configuration, requiring the connection of an upper air pipe through which excess air will be removed from the radiators. With absence basement additional problems may arise due to the need to install the boiler below the level of the radiators.

Both the lower and upper circuits of a two-pipe heating system can be made in a horizontal or vertical configuration. However, vertical networks, as a rule, are made with bottom wiring. With this installation, there is no need to install a powerful pump for forced circulation, since due to the difference between the temperatures in the return and supply pipes, a strong pressure drop is created, increasing the speed of movement of the coolant. If, due to the specific layout of the building, such installation cannot be done, a main line with overhead routing is installed.

Making a two-pipe system with your own hands (video)

Selecting pipe diameters and rules for installing a two-pipe network

When installing two-pipe heating, it is extremely important to choose the correct pipe diameter, otherwise you may get uneven heating of radiators located far from the boiler. Most boilers for domestic use have a diameter of the supply and return pipes of 25 or 32 mm, which is suitable for a two-pipe configuration. If you have a boiler with 20 mm pipes, it is better to opt for a single-pipe heating system.

Size chart available on the market polymer pipes consists of diameters 16, 20, 25 and 32 mm. When installing the system yourself, you need to take into account the key rule: the first section of the distribution pipe must match the diameter of the boiler pipes, and each subsequent pipe section after the branch tee to the radiator is one size smaller.

In practice, it looks like this: a diameter of 32 mm comes out of the boiler, a radiator is connected to it through a tee with a 16 mm pipe, then after the tee the diameter of the supply line is reduced to 25 mm, at the next branch to the radiator line 16 mm after the tee the diameter is reduced to 20 mm and so on. If the number of radiators is greater than the standard sizes of pipes, it is necessary to divide the supply line into two arms.

When installing the system yourself, adhere to the following recommendations:

• the supply and return lines must be parallel to each other;
• each outlet to the radiator must be equipped with a shut-off valve;
• distribution tank, if installed in attic when installing a network with top wiring, it is necessary to insulate it;
• pipe fastenings on the walls should be placed in increments of no more than 60 cm.

When setting up a system with forced circulation, it is important to correctly select the power of the circulation pump. Specific choice is done based on the size of the building:

• for houses with an area of ​​up to 250 m2, a pump with a capacity of 3.5 m3 / hour and a pressure of 0.4 MPa is sufficient;
• 250-350 m2 – power from 4.5 m3/hour, pressure 0.6 MPa;
• over 350 m 2 - power from 11 m 3 / hour, pressure from 0.8 MPa.

Despite the fact that it is more difficult to install two-pipe heating with your own hands than a one-pipe network, such a system, due to its high reliability and efficiency, fully justifies itself during operation.

The heating system is divided into two types: single-pipe and double-pipe. Obviously, it is most profitable to install a more efficient one that will not only cope with its functions, but will also serve you for many years. So as not to be left “in the cold” and not make a mistake with the choice of heating system.

You need to thoroughly understand which heating system is best for you and why.

Thus, you will know which system is better from a technical point of view and how to choose it, taking into account your budget.

High water pressure ensures natural cycle, and antifreeze makes the system more economical.

Disadvantages of a one-pipe system - a very complex thermal and hydraulic calculation of the network, since if an error is made in the calculations of devices, it is very difficult to eliminate it.

Also, this is a very high hydrodynamic resistance and an involuntary number of heating devices on one line.

The coolant flows into everything at once and is not subject to separate adjustment.

In addition, there are very high heat losses.

In order to be able to regulate the operation of individual devices connected to one riser, bypasses (closing sections) are connected to the network - this is a jumper in the form of a piece of pipe connected by the forward and return radiator pipes, with taps and valves.

To be able to regulate the temperature of each separately, the bypass allows you to connect auto-thermostats to the radiator.

In addition, this also makes it possible, in the event of a breakdown, to replace or repair individual devices without turning off the entire heating system.

Single-pipe heating is divided into vertical and horizontal:

• vertical – this is connecting all batteries in series from top to bottom.
• horizontal - This is a serial connection of all heating devices on all floors.

Due to the accumulation of air in the batteries and pipes, so-called traffic jams occur, which is a disadvantage of both systems.

Installation of a one-pipe system

The connection is made according to the diagram, using taps to vent the radiators, which close the taps and plugs.

System pressure testing - after which coolant is poured into the battery and the system is directly adjusted.

Two-pipe heating system

The advantage of a two-pipe heating system – this is the installation of automatic thermostats, which gives full control of the temperature in individual rooms.

This also includes the independence of operation of circuit devices, which is ensured by a special collector system.

The difference between a two-pipe and a one-pipe system is that the first can be connected extra batteries after connecting the main ones, as well as the possibility of extension in vertical and horizontal directions.

Unlike the single-pipe system, it is also possible to easily correct errors.

Disadvantages of this system minimal if you have sufficient quantity material resources and have the opportunity to call a specialist.

Installation of a heating system with lower horizontal piping

This system allows you to locate an open tank in a convenient warm place. Also, it is possible to combine expansion and supply tanks allowing you to use hot water directly from the heating system itself.

In systems with forced circulation, to reduce pipe consumption, the outlet and supply risers are located at the level of the first.

In the process of designing a heating system, the question arises of how best to connect radiators - according to single-pipe scheme or according to two-pipe?

Each connection method has its own characteristics, advantages and disadvantages. To choose the wiring diagram correctly, you need to define it efficiency for your home. What is the difference between one- and two-pipe systems? And by what criteria do they make a choice?

Single-circuit heating circuit

The single-pipe system is the most simple option connections between radiators and boiler. It is used for heating small and medium-sized rooms.

It has an important advantage - it gives possibility to organize work independently of the electric circulation pump.

The main advantages of single-pipe wiring are simplicity and independence from electricity. How does it work?

Principle of operation

In a single-pipe scheme, the same pipe performs the supply function hot water and return cold. Main pipe connects in series all radiators. At the same time, in each of them the water loses part of the heat. Therefore, in a single-pipe heating circuit there are hotter radiators at the beginning, and cooler ones at the end of the circuit.

Attention! The warmest rooms will be those located immediately after the boiler. The rooms located in front of the boiler entrance will be cool. This must be taken into account when building a house.

With such a heating scheme, large rooms should be the first from the boiler - kitchens, dining rooms, halls. And the last ones are small bedrooms.

Arrangement

Single-pipe wiring is ideal for organizing the movement of coolant by gravity. At correct location heating devices, the water inside the pipes will move independently, without the help of a circulation pump. To do this it is necessary to organize significant height difference between the boiler and the distribution manifold.

The coolant heating boiler is located as low as possible- on the ground floor of the premises or in the basement.

The collector through which heated water is distributed is located as high as possible - under the ceiling of the top floor or in the attic. Water rises from the boiler to the collector during the heating process.

When heated, it expands, becomes lighter and therefore - rises up. Then from the distribution manifold it enters the supply pipe, then into the radiators and returns to the heating boiler.

Reference! In heating big house single-pipe circuit can be divided for several successive connections. In this case, they will all start from the distribution manifold and end in front of the boiler.

In addition to the boiler, distribution manifold and radiators, the circuit must be built expansion tank. The expansion coefficient of water depends on the amount of heating, at different heating Water expands in different ways. In this case, a certain amount of coolant is displaced from the system. To collect and store displaced water, a tank.

home driving force coolant - temperature rise of water. The higher the temperature of the coolant, the greater the speed of water movement through the pipes. Also, the gravity flow rate is affected by the diameter of the pipes, the presence of corners and bends in them, the type and quantity locking devices. In such a system they install only Ball Valves. Conventional valves even in open position create a barrier to the movement of water.

Vertical and horizontal wiring: differences

More often a single-pipe scheme assembled on one floor level- in the horizontal plane.

Pipes are laid along the floor, connecting radiators into neighboring rooms located on the same floor. This arrangement is called horizontal.

Less often the scheme is assembled V multi-storey building vertically. In this case, pipes connect rooms located above each other. This heating scheme is called vertical. What is the difference between the two wiring, and which one is better for a private home?

Vertical diagram:

• Requires connection of specific batteries - elongated in height. Most radiators on the market are designed to be included in a horizontal system - they are elongated in width. If radiators are connected incorrectly, their operating efficiency will be reduced.
• Narrow radiators for vertical wiring provide good heating small premises. And worse - large rooms.
• Is different low probability of pipe airing, the formation of air jams - air is removed through a vertical riser.

Attention! Vertical layout is optimal for large quantity floors at small areas rooms.

Horizontal layout:

• Provides great selection of radiators.
• Works more efficient vertical, which is due to the physics of coolant movement through pipes.

Horizontal wiring is used for heating installations on the same floor. In a house with several floors, water is transferred between floors through a vertical riser. Thus, for two- or three-story cottage will be optimal combined system with elements of vertical and horizontal wiring.

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Pros and cons of Leningrad

Let us list the advantages of single-pipe heating:

• Simple and inexpensive arrangement , which provides a small number of pipes, connectors, pipes and other additional devices in the system.
• Ideal scheme for movement of water by gravity and for the organization gravity heating system, without the need for a circulation pump.

Flaws:

• Uneven heating rooms - there are hot and cool rooms.
• Not suitable for heating big houses, whose area more than 150 sq.m, or in the heating system of which it is built more than 20 radiators.
• Large diameter makes pipes unaesthetic their appearance on the walls.

Dual-circuit battery wiring

A two-pipe heating system differs from a single-pipe heating system by dividing it into two pipes - coolant supply and return. It ensures uniform heating of all rooms. This type of wiring is used in most new houses.

Principle of operation

In a two-pipe scheme, water from the boiler flows to the radiators through supply pipe (main).

Near each radiator, the supply line has a connecting inlet pipe, through which the coolant enters the battery. The supply line ends near the last radiator.

In addition to the incoming pipe, each radiator has outlet pipe. He connects it to the return pipe. The return line starts from the first battery and ends at the entrance to the boiler.

Thus, the heated water flows into the radiators evenly and at the same temperature. From each radiator, water is discharged into the return pipe, where it is collected and supplied to the boiler for subsequent heating. Thanks to this movement of the coolant, all rooms in the room are heated equally.

What is the difference

A two-pipe heating system includes elements of a single-pipe system and additional devices. In addition to the boiler, radiators, supply and return water collection pipes (the so-called return), the two-pipe scheme also includes circulation pump.

The large length of the lines, the presence of corners and turns in the supply pipes complicate the movement of the coolant. That's why necessary his forced circulation electric pump.

Photo 1. Circulation pump model 32-40, voltage 220 Volts, manufacturer - Oasis, China.

Also in the two-pipe circuit there is more taps, regulating water supply and quantity. Such a tap is installed in front of each radiator - at the inlet and outlet.

Classification by location

In a horizontal two-pipe system, pipes connect the radiators horizontally. This scheme works in heating one-story house or one floor of a multi-storey cottage.

In a vertical two-pipe system, pipes connect radiators located one above the other in one “riser”. However, there are differences from the single-pipe vertical scheme. Here - thanks to the presence of a supply and return pipe, in vertical heating can be used batteries of any width — multi-section(since the supply and return risers can be located at a distance from each other). Therefore, the efficiency of two-pipe vertical heating is higher.

Reference! It is desirable that the batteries of rooms located one above the other have the same number of sections. It's easier to lay this way vertical pipe return lines

Bottom and top harness: which is more effective?

The terms “bottom” and “top” trim mean way to connect batteries to the system heating. At bottom harness incoming water enters the battery through the lower pipe.

If it also comes out of the radiator at the bottom, then the efficiency of the radiator will be reduced by 20-22%.

If the outlet pipe is located at the top, the efficiency of the radiator will be reduced. by 10-15%. In any case, with lower water supply to the batteries, the heating efficiency decreases.

At top harness(supply) the incoming pipe is connected to the radiator at the top. In this case, the movement of the coolant is organized more efficiently, the battery will work by 97-100% (97% - if the inlet and outlet pipes are located on one side of the radiator, and 100% - if the inlet pipe is on one side from above, and the outlet pipe is on the other side from below).

Advantages and disadvantages

Advantages:

• Suitable for heating large private houses, in this case the circulation pump necessarily crashes into the system.
• Heats all rooms on the floor or in the riser evenly.

Flaws:

• Costs expensive single-pipe system, since twice as many materials are required - pipes between the boiler and radiators, as well as connecting devices, taps, and valves.
• An electric circulation pump makes the system work dependent on the availability of electricity.

Important! An increase in the number of pipes and the amount of coolant in the system leads to increase in hydrodynamic resistance and does not allow water to move by gravity. Forced circulation and a working circulation pump are required.