A two-pipe heating system has a more complex architecture, and its installation requires a large amount of materials. And, nevertheless, this system is more in demand than a simple one-pipe heating system. The two-pipe heating system consists of two closed circuits, one of which serves to supply the heated coolant to the radiators, and the second to drain the already used (cooled) liquid. The use of this system is acceptable for all types of buildings, provided that the layout of the premises itself allows its installation.

Two-pipe heating system

Types and advantages of a two-pipe heating system

A technical feature of this type of heating system is that it consists of two pipelines. One is used to transport the coolant heated in the boiler directly to the heating sources - radiators. And the second circuit is necessary for the outflow from the radiators of the already used coolant - the cooled liquid, which gave up its heat.

A double-circuit heating system has a significant advantage over a single-pipe one, in which the heated coolant loses part of the heat even before it reaches the radiators.

In a system such as a passing two-pipe system heating, there is an equal temperature of the coolant entering simultaneously into the heating devices of the system.

Scheme of a two-pipe heating system

Many people believe that the cost of a two-pipe system, compared to a simpler one-pipe system, is almost doubled - after all, it is necessary to take twice as many pipes. But it's not. The fact is that for the correct construction of a properly functioning one-pipe system, pipes of a larger diameter should be used, since they contribute to a more active movement of the coolant and the waste fluid. And when creating a two-pipe system, pipes of a much smaller diameter are used, the cost of which is lower.

The same situation is observed when purchasing additional components of the system - valves, spurs, connecting elements. Larger products cost more. That is, we can draw a simple conclusion - in fact, the purchase of materials for a two-pipe system will cost you not much more than for a single-pipe system. But the efficiency of its work is much higher.

A significant advantage of a two-pipe system is another aspect - in such a heating system, it is possible to install valves on each radiator, through which you can control the heating level of the element. In addition, by means of such valves it is also possible to significantly save the consumption of water and electricity for its heating.

It should be noted that the scheme of a two-pipe heating system has another advantage. It lies in the relatively greater aesthetics.

Many owners of houses with a one-pipe system are often upset that a very thick heating pipe cannot be hidden - and this significantly spoils the overall impression of the room. While the pipes used in a more complex two-pipe system are thinner - and it will not be difficult to hide them. And even if the pipes are in plain sight, they do not attract much attention.

Given all the obvious advantages of a two-pipe system - greater efficiency, low cost and aesthetics, you can confidently opt for it. What most owners do country houses.

There are two types of two-pipe heating system - horizontal and vertical 2-pipe heating system. The main difference between these types is in the axis of the pipeline. Through these pipes, all elements of the heating system are connected. Of course, each type has its own disadvantages and advantages. The following advantages can be called common to both types - excellent hydraulic stability and high level heat transfer.

It should be installed in one-story buildings, where the heating pipeline is quite long. In such houses, connecting heating radiators to a horizontally located system is the most practical solution to the issue.

It is somewhat more expensive than horizontal. However, since the riser is located vertically, this allows it to be used even in multi-storey buildings. In addition, each floor separately cuts into the central heating riser. In addition, the advantages of the vertical type of heating system also lie in the fact that air does not accumulate in it - when bubbles occur, they immediately rise vertically, directly into the expansion tank.

Whatever type of system you choose, it should be borne in mind that it is imperative to carry out balancing. When choosing a vertical system, balancing a two-pipe heating system is required by the riser itself. When the horizontal adjustment of a two-pipe heating system takes place, loops are exposed to it.

Types of wiring for a two-pipe system

Regardless of which type of two-pipe heating system you choose for your own home, there is another system for separating it - according to the principle of wiring. In the photo you can see two different wiring diagrams. Each has its own advantages and disadvantages of a two-pipe heating system.

With it, the laying of a pipeline with a hot coolant is carried out in the basement or basement. It is also allowed to lay pipes in the underground. With this type of laying, it should be borne in mind that the pipes for returning the waste heat carrier back to the boiler must be located even lower. The use of the principle of horizontal wiring provides for the need for some deepening of the boiler - only in this case the water will move from the radiators to heating element as quickly as possible. In addition, there is a need to connect an additional line to the circuit - overhead. With its help, it will be possible to remove air from the system.

For its construction, it is necessary to have expansion tank at the highest point of the pipeline. The branching of the system is also carried out there. More practical, top wiring cannot be installed in buildings that do not have an attic.

You can choose the most suitable type of wiring, regardless of which type of supply pipe layout is used in your home.

However, there are some requirements that must be taken into account. In particular, for houses in which a two-pipe vertical system heating, the most appropriate is the use of lower wiring. This is due to the fact that two-pipe heating with a lower wiring makes it possible to use the pressure that occurs in the system with a rather large difference between the coolant and the waste fluid with maximum benefit. Of course, if the architectural features of the building do not allow the use of the lower wiring, the use of the upper one is acceptable.

It should be borne in mind that the use of upper wiring for both supplying coolant to radiators and returning return to the boiler is not the best solution, since the accumulation of sludge in the lower elements of the system is possible.

In fact, the classification of a two-pipe heating system is very multifaceted.

Another principle of separation is the direction of the flow of the coolant. According to this criterion, the system can be:

• straight-through. In this case, the direction of movement of the coolant and the reverse direction coincide.
• dead end. In the case of using such a scheme as a two-pipe dead-end heating system, hot and waste coolant move in different directions.

Modern systems can be equipped with a special pump, due to which there is a more active movement of the coolant. At the same time, systems with natural circulation are often used, in which additional equipment is not used. If it is intended to use a two-pipe system in a two-story house, then such a two-circuit heating should certainly be equipped with a pump.

Heating system with circulation pump

But when mounting a two-pipe heating system in a one-story room, you can do without a pump, using some laws of physics to naturally move the coolant. At the same time, it is important to take into account that for a more active natural circulation of the coolant, it is necessary to lay heating pipes with a slope directed towards the heating boiler.

However, regardless of the system you use (with forced and natural circulation), the slope must be present.

For systems with forced circulation, it is necessary in case of an unexpected power outage or pump breakdown. In this case, the slope allows the coolant to circulate naturally.

Calculation

When planning a two-pipe system, it is important to carry out a preliminary calculation of the system of a two-pipe heating system, using such a guideline as a preliminary system diagram (all elements must be indicated on it) and special axonometric formulas and tables.

This simple hydraulic calculation of a two-pipe heating system allows you to determine the optimal diameter of the pipes required for normal functioning systems, the volume of radiators used. The most commonly used types of calculations are:

• by pressure loss. This method assumes an equal level of coolant temperature in all parts of the system.
• calculations that take into account the value of conductivity and resistance. In this case, it is assumed different meaning temperature indicators.

As a result of applying the first method, very accurate data can be obtained showing the level of resistance in the circuit. The second method shows the temperature in each individual segment of the system, as well as the approximate flow rate of the coolant.

Principles of installation of a two-pipe system

When installing a two-pipe system, a fairly large number of requirements and rules should be taken into account. Only their full observance will allow you to create the most efficient heating system and produce correct installation two-pipe heating system:

• a two-pipe closed heating system or an open one consists of two circuits - the upper one serves to supply the heated coolant to the radiators, and the lower one - to drain the waste fluid.
• pipes should be laid with a slight slope. It must be made towards the last radiator of the system.
• the upper and lower lines must be parallel.
• the central riser must be insulated - otherwise, the coolant will be lost at the stage of its movement to the radiators.

• a two-pipe reversible heating system should have several taps that will allow you to drain water from individual sections in case of a need for repairs.

• the piping should contain as few corners as possible.
• the expansion tank should be located at the top of the system.
• taps, connections and other elements of the system must be equal to the diameter of the pipes used.
• if the pipeline is used steel pipes, it is necessary to create a system of fasteners that will support the pipe. The distance between the supports should not exceed 1.2 meters.

The sequence of connecting elements in how to make a two-pipe heating system is simple:

• a central heating riser is connected to the heating boiler.
• in the upper part, the central riser is connected to the expansion tank.
• a splitter is removed from the tank, directing the pipes to the radiators.
• the waste liquid discharge line is laid parallel to the supply pipes. It should be embedded in lower part heating boiler.
• the pump is installed at the most convenient point - most often at the inlet (outlet) of the boiler.

This type of heating system is quite efficient. Today, there are a large number of models of boilers that involve automatic control of the level of heating of the coolant. A video on how to make double-circuit heating with your own hands can be viewed below.

In apartments and private houses, an integral part of comfort is the provision of heat. Mostly use water heating. Water heating Available in single and double pipe configurations. In the first case, the water, passing through a closed circuit, cools down greatly. Each subsequent radiator receives a colder fluid. The two-pipe system eliminates this disadvantage.

A two-pipe heating system is effective for a private house. These designs have become more popular. The complexity of installation and a slightly higher consumption of materials pay off with clear advantages.

Advantages of two-pipe heating:

1. Each radiator receives an equally heated coolant, increasing the air temperature in the room.
2. Possibility to regulate the heat of each battery by setting a thermostat.
3. If one of the systems breaks down, repairs can be carried out without stopping the heating. To do this, it is necessary to install locking elements.
4. For installation, you can use pipes of small diameter, significantly saving money.
5. Installation in a room of any size.

A distinctive feature of the system is the connection to each radiator 2 pipes. Through the first, heat enters the battery, the second removes the cooled liquid from the device. This design allows you to effectively heat the room.

Layout of pipes of a two-pipe heating system

The two-pipe wiring diagram is of 2 types - vertical and horizontal. In the first case, the heating elements are located vertically along one riser, which is typical for apartment buildings. In most cases, the coolant is fed upwards, the outlet descends by gravity.

In the horizontal version, the batteries are arranged in one line. Such wiring is inherent in single-story buildings.

The two-pipe design can be open and. Any heating includes an expansion tank as part of the elements. When heated, the pressure in the pipes increases, and the compensation system allows you to maintain the required operating level. The device is located at the highest point, usually in the attics of houses. With open wiring, the liquid in the tank comes into contact with air. Part of it evaporates, so such a system requires constant monitoring. In the closed type, the design is equipped with a membrane, and does not require constant attention.

Circuit advantage:

• A more aesthetic appearance of the room, the pipes are hidden under the radiators and are not conspicuous;
• For passage to the radiators, one opening is required;
• Reduced heat loss.

All heating systems can be made with natural and forced circulation. The choice of design is influenced by the top or bottom water supply. For the bottom supply, it is necessary to install forced water circulation. Pipes from the boiler to the radiators are laid at floor level, just below the batteries. Around the entire perimeter of the room, 2 pipes are passed: distribution and return. They are connected to each radiator using fittings and tees. Such a system can be constructed from metal-plastic or polypropylene pipes independently, without resorting to the services of specialists.

Option with top wiring in a two-pipe heating system of a private house

In private houses, you can install both lower and upper distribution. For upper wiring, the use of natural water circulation is preferable. Distribution with hot coolant is pulled from the boiler to the ceiling, then laid along the perimeter of the building.

Design description:

• Branches are vertically lowered from the upper pipe to the radiators;
• The reverse stroke is laid at the level of the floor;
• Connect both pipes to radiators;
• For physical circulation, the slope of the pipe should be 3-5ᵒ, while the expansion tank is installed at the highest point of the circuit.

The heating system of natural circulation starts to work when the water is heated. The coolant becomes lighter and rushes up, reaching highest point circuits, then descends through the pipes into the radiators, cooling down and becoming heavier, goes back to the boiler.

The lower the room temperature, the faster the circulation of water in the batteries.

The maximum effect from the top distribution can be obtained in a 2-storey building. Natural circulation will be stimulated by the difference in the height of the batteries on the 2nd floor and the installation of a boiler in the basement. The disadvantage of the upper scheme is the external aesthetic appearance, in addition, part of the heat goes up. You can compensate for the disadvantage by combining one-pipe and two-pipe heating. For example, make a single-pipe warm floor on the 2nd floor, on the 1st conduct a two-pipe wiring.

Accurate calculation of a two-pipe heating system

Before starting work, it is necessary to draw up a heating scheme, decide on the material, and make a hydraulic calculation. It is necessary to calculate the pressure drop in the back section or to calculate the diameter of the pipe.

The calculation is carried out taking into account the following factors:

• The inner surface of the pipes and its roughness;
• Section diameter;
• Number of pipe bends;
• Pressure drop between supply and return;
• The number of radiators and their cross section;
• Locking elements.

When carrying out the calculation, formulas and an axonometric table are used. You can use a special software program. The most loaded ring or contour is taken as the main object. As a result of calculations, the optimal speed of movement should be from 0.3 to 0.7 m/s.

At a higher speed, the heating will make noise, at a lower speed, there will be a strong temperature variation.

After the calculations, they acquire pipes of effective diameter, the required number of radiators, a boiler, fittings, squeegees, an expansion tank, a circulation pump, if such a need exists.

Do-it-yourself steps for installing two-pipe heating

Installation of the heating system begins with the installation of the boiler. The heat generator on gas and electricity is located in any room. For liquid and solid fuel boilers, a separate niche is required. When installing radiators, it is necessary to take into account the pipeline slope of 1-2% in relation to the entire length of the pipe.

Work plan:

1. Boiler installation.
2. The main pipe is discharged from the heat generator with hot water passing through all radiators.
3. Parallel to the first, a second line with a reverse course is carried out.
4. With a forced heating option, a circular pump is inserted.
5. Install radiators. Batteries are hung on special brackets. All radiators must be at the same level. For ease of use, they are equipped with shut-off valves at the entry and exit points. Batteries are connected in several ways: side, diagonal, bottom connection. The most effective side and diagonal design.
6. The heating system is completed by installing pipes of related units, installing an expansion tank and additional elements.

The main line should not contain straight and sharp corners, as resistance will increase. Taps and valves must match the dimensions of the pipes. With a design with top wiring, the expansion tank is placed in an insulated attic. After completing all installation work, it is time to connect the system.

To do this, close all the taps, and be sure to slowly fill the supply circuit.

Next, the valve of the first battery is opened, and with the help the air is bled until an even jet exits. The element is closed and the radiator outlet cock is opened. These manipulations must be carried out with each radiator. All found defects are eliminated.

Do-it-yourself two-pipe heating of a private house (video)

Do-it-yourself installation of a two-pipe system will take large quantity time, will ultimately provide efficient and practical heating, and will save on installation work. It is important to choose the right best option for the home, and make a competent calculation of the system parameters. Skillful hands and following the instructions will transform the house, making it cozy and warm.

Examples of heating wiring in a private house (photo)

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Heating systems: one-pipe, two-pipe.

Nowadays, 2 different heating systems are installed in houses: one-pipe or two-pipe. Each has its own design features. Two-pipe heating systems are the most popular.

Nowadays, 2 different heating systems are installed in houses: one-pipe or two-pipe, and each has its own characteristics.

Single pipe heating system

In order to understand what it looks like, look at the ring with a stone. In the heating system, the boiler plays the role of a stone. As for the ring, these are pipes of a specific diameter that run along the perimeter of the entire building. Radiators are connected to them. The coolant is often water and sometimes antifreeze. The functionality of a single-pipe heating system is based on the gradual release of heat by water. After passing through the ring, the water returns to the boiler with a lower temperature.

This scheme usually has a natural circulation of the coolant. Hot water first served on top floor. And then, passing through the radiators, the part of the heat that has been given off descends to the boiler, having carried out full circulation. A single-pipe heating system can be supplemented with elements:

• thermostatic valves;
• radiator regulators;
• balancing valves;
• ball valves.

Thanks to them, it becomes more balanced and it becomes possible to change the temperature in certain radiators.

Distinctive features of the heating system

The biggest plus is electrical independence, and the minus is the pipes, which have a large diameter and the wiring is sloped.

Compared to the two-pipe option, there are quite a few advantages:

• pipes can be diverted to the “warm floor” system or heating radiators can be connected;
• it can be carried out regardless of the layout of the room;
• it covers the entire perimeter with a closed ring;
• it is less material-intensive and has a lower cost.

In use, it may sometimes be difficult to circulate through the pipes, but this is easily solved by installing pump equipment. It produces competent circulation of the coolant through the pipes.

The vertical single pipe scheme is a popular example of wiring in apartment buildings.

And the horizontal one is used mainly for heating huge rooms and is used very rarely in private buildings (mainly in small one-story houses). Here the supply pipe bypasses the heaters, which are on the same level. The water in each radiator cools down and, approaching the last heating devices, it becomes already significantly cooled. This scheme will help reduce installation and piping costs, but has two drawbacks.

Firstly, this is a problem with heat regulation in any heating device. You can not increase heat transfer, reduce it, turn off the radiator. In installation practice, there is a jumper - a bypass, which allows you to turn off the radiator without shutting down the system. Heating of the room is carried out indirectly by means of a riser or supply pipes. Another drawback is that you need to use radiators of various sizes. In order for the heat transfer to be the same, the first heater must be very small, and the last one must be large. A horizontal single-pipe heating scheme is also used.

Two pipe system

There are several types of it. The principle of operation is the same and consists in the following. Hot water rises through the riser and from it enters the radiators. And from them it enters the pipeline through highways and return lines, then into the heating device. With this system, the radiator is served by two pipes at the same time: return and supply, therefore it is called two-pipe. Water in this system is supplied directly from the water supply. She needs an expansion tank, which can be either simple or with water circulation.

The composition of the simple includes a container with 2 pipes. One is a water supply riser, and the second is used to drain excess liquid.

A more complex design has 4 pipes. 2 pipes provide circulation, and 2 others are needed for control and overflow, they also monitor the water level in the tank.

Two-pipe systems can be operated using a circulation pump. Depending on the circulation method, it can be co-current or dead-end. In the second, the movement of warm water is completely opposite to the direction of the already cooled one. Such a scheme is characterized by the length of the circulation rings, which depends on the distance of the heater to the boiler. Circulation rings have equal length in systems with one-way water flow, all devices and risers work under equal conditions.

A two-pipe heating system has a large set of advantages compared to a single-pipe:

• the possibility of distributing the heat supply in different rooms;
• can be used on one floor;
• locking systems of the return and supply risers are located in the basement - this significantly saves the area of ​​\u200b\u200bliving premises;
• minimizing heat loss.

The only drawback is the considerable consumption of materials: you need 2 times more pipes than for a single-pipe connection. Also, the disadvantage is the low water pressure in the supply line: taps will be needed to bleed air.

The horizontal closed two-pipe scheme comes with a lower and upper wiring. The advantage of the lower wiring: sections of the system can be put into operation gradually, as the floors are built. The vertical two-pipe scheme can be used in houses with variable number of floors. Any of the varieties of two-pipe schemes is more expensive than single-pipe horizontal wiring; for the sake of comfort and design, it is worth giving preference to a two-pipe scheme.

One-pipe and two-pipe systems: comparison

Single-pipe systems, unlike two-pipe systems, do not have return risers. The heat carrier from the boiler, under the action of the circulation pressure or the pump, enters the upper heating devices. Cooling, he returns back to the supply riser and goes down. The lower radiators receive a mixture of coolant from the riser and from the upper radiators. Passing through all radiators and other heat consumers, the coolant returns to the boiler, where the process is repeated again. The temperature of the coolant decreases when passing in a circle, and therefore the lower the radiator is, the larger the heating surface should be.

For one-pipe systems, there are 2 schemes. This is a flow and mixed scheme. The flow circuit has a feature - the complete absence of jumpers between the supply and exit from the radiator. These schemes are almost never used in the installation of heating systems due to their impracticality. One battery breaks, and the riser needs to be turned off, because there is no way to turn on the coolant bypassing it. The advantage of single-pipe systems is the lower cost of building materials and ease of installation. Installation of single-pipe systems requires top wiring.

A two-pipe heating system can be operated in any houses: multi-storey, one-story, etc. A two-pipe heating system is easy to implement with conventional circulation, since its configuration makes it possible to organize a circulation pressure, do not forget that the boiler must be installed below the level of the radiators. It is possible to organize a heating system with forced circulation, simply by placing circulation pump into the contour.

If it is possible to implement a ring scheme, then it must be done. A two-pipe system usually needs to be installed where there are difficulties with gas, power outages, etc. For this system, a solid fuel boiler and pipes with a larger diameter are enough. Bring firewood or coal, and do not worry about frost.

Methods for installing heating systems

Mounting methods depend on the characteristics of the system.

The cost of heating installation work is determined by the features specific project, and only specialists with experience in such work can calculate everything.

If it is necessary to install heating with normal circulation, the installation of a system with a top spill will be effective. The water circulates through the pipes itself. Bottom spill systems do not provide effective work without circulation pump.

Scheme of the collector (beam) wiring of the heating system.

Installation methods are also classified:

• by type of wiring (collector, beam);
• by the number of risers;
• by type of pipe connection (side or bottom).

Heating installation with bottom pipe connection is the most popular. It becomes possible not to run the pipeline directly along the walls, but to hide it under the floor or baseboard. An aesthetic appearance of the room is achieved.

The main classification of mounting methods is carried out in complete dependence on the scheme. You can install a two-pipe heating system or install single pipe heating. In the second case, the water flows through the pipeline through the radiators, cooling along the way. The last radiator will be colder than the first. With a two-pipe system, 2 pipes are connected to the radiators: return and direct. This allows you to create the same temperature of the radiators. The first option is the simplest and cheapest, due to the low cost of materials. But it is only effective in small houses. If your house is over 100 square meters or it has more than 1 floor, it is better to install two-pipe heating.

The two-pipe system gives an excellent choice of ways to install radiators:

• serial connection;
• parallel connection;
• lateral one-way connection;
• diagonal connection.

Depending on the location of the supply risers, there are certain ways to install autonomous heating:

1. Heating with horizontal wiring.
2. Heating with vertical wiring.
3. Heating without risers with supply and return lines.

A single pipe system is cheaper. If you care about the quality of the heating system, there is no need to spare money for a two-pipe wiring, because we get the opportunity to control the heat in the rooms.

The water heating system can be one-pipe and two-pipe. Two-pipe is called so because two pipes are needed for operation - one from the boiler is supplied with hot coolant to the radiators, the other is cooled down from the heating elements and fed back into the boiler. Boilers of any type on any fuel can work with such a system. Both forced and natural circulation can be implemented. Two-pipe systems are installed in both one-story and two- or multi-story buildings.

Advantages and disadvantages

The main disadvantage of this method of organizing heating follows from the method of organizing the circulation of the coolant: a double number of pipes compared to the main competitor - a single-pipe system. Despite this situation, the cost of purchasing materials is slightly higher, and all due to the fact that with a 2-pipe system smaller diameters of both pipes and, accordingly, fittings are used, and they cost much less. So as a result, the cost of materials is higher, but not significantly. What is really more is the work, and accordingly it takes twice as much time.

This disadvantage is compensated by the fact that a thermostatic head can be installed on each radiator, with the help of which the system is easily balanced in automatic mode, which cannot be done in a single-pipe system. On such a device, you set the desired temperature of the coolant and it is constantly maintained with a small error (the exact value of the error depends on the brand). In a one-pipe system, it is possible to realize the ability to regulate the temperature of each radiator separately, but this requires a bypass with a needle or three-way valve, which complicates and increases the cost of the system, negating the savings in money for the purchase of materials and installation time.

Another disadvantage of a two-tube is the impossibility of repairing radiators without stopping the system. This is inconvenient and this property can be bypassed if placed near each heater on the supply and return Ball Valves. By blocking them, you can remove and repair the radiator or heated towel rail. The system will continue to function indefinitely.

But such an organization of heating has an important advantage: unlike a single pipe, in a system with two lines, water of the same temperature flows to each heating element - immediately from the boiler. Although it tends to take the path of least resistance and will not spread beyond the first radiator, installing thermostatic heads or flow control valves solves the problem.

There is another advantage - lower pressure losses and easier implementation of gravity heating or the use of smaller pumps for systems with forced circulation.

Classification of 2 pipe systems

Heating systems of any type are divided into open and closed. In the closed ones, a membrane-type expansion tank is installed, which makes it possible for the system to function at elevated pressure. Such a system makes it possible to use not only water as a coolant, but also ethylene glycol-based compounds, which have a lower freezing point (up to -40 ° C) and are also called antifreezes. For the normal operation of equipment in heating systems, special compounds designed for these purposes should be used, and not for general purposes, and even more so, not for automobiles. The same applies to the additives and additives used: only specialized ones. It is especially tough to adhere to this rule when using expensive modern boilers with automatic control - repairs in case of malfunctions will not be guaranteed, even if the breakdown is not directly related to the coolant.

In an open system, an open-type expansion tank is built in at the top point. A pipe is usually connected to it to remove air from the system, and a pipeline is also organized to drain excess water in the system. Sometimes from expansion tank can take hot water for economic needs, but in this case it is necessary to make the system recharge automatically, and also not to use additives and additives.

Vertical and horizontal two-pipe system

There are two types of organization of a two-pipe system - vertical and horizontal. Vertical is used most often in multi-storey buildings. It requires more pipes, but the possibility of connecting radiators on each floor is easily realized. The main advantage of such a system is the automatic air outlet (it tends to rise and exits there either through the expansion tank or through the drain valve).

The horizontal two-pipe system is used more often in one-story or, at most, in two-storey houses. To bleed air from the system, Mayevsky taps are installed on the radiators.

Two-pipe horizontal heating scheme for a two-story private house (click on the picture to enlarge)

Top and bottom wiring

According to the method of distributing the supply, a system with an upper and lower supply is distinguished. With the upper wiring, the pipe goes under the ceiling, and from it the supply pipes go down to the radiators. The return line runs along the floor. This method is good in that you can easily make a system with natural circulation - the difference in height creates a flow of sufficient force to ensure a good circulation rate, you just need to observe the slope with a sufficient angle. But such a system is becoming less and less popular due to aesthetic considerations. Although, if at the top under the hanging or stretch ceiling, then only pipes to the devices will remain in sight, and they, in fact, can be monolithic into the wall. Upper and lower wiring are also used in vertical two-pipe systems. The difference is shown in the figure.

With lower wiring, the supply pipe goes lower, but higher than the return. The supply tube can be placed in the basement or semi-basement (the return line is even lower), between the rough and finish floor, etc. The coolant can be supplied / removed to the radiators by passing the pipes through the holes in the floor. With this arrangement, the connection is the most hidden and aesthetic. But here you need to select the location of the boiler: it does not matter in its position relative to the radiators - the pump will “push through”, but in systems with natural circulation, the radiators must be above the level of the boiler, for which the boiler is buried.

The two-pipe heating system of a two-story private house is illustrated in the video. It has two wings, the temperature in each of which is regulated by valves, the lower type of wiring. System with forced circulation, because the boiler hangs on the wall.

Dead-end and associated two-pipe systems

A dead-end system is such a system in which the movement of the coolant supply and return flow is multidirectional. There is a system with passing traffic. It is also called the Tichelman loop / scheme. The latter option is easier to balance and configure, especially with long networks. If radiators with the same number of sections are installed in a system with a passing movement of the coolant, it is automatically balanced, while with a dead-end circuit, a thermostatic valve or a needle valve will be required on each radiator.

Even if radiators of different numbers of sections and valves / valves are installed with the Tichelman scheme, it is still necessary to install, then the chance to balance such a scheme is much higher than a dead-end one, especially if it is quite long.

To balance a two-pipe system with multidirectional movement of the coolant, the valve on the first radiator must be screwed very tightly. And a situation may arise in which it will need to be closed so much that the coolant will not flow there. It turns out then you need to choose: the first battery in the network will not heat, or the last one, because in this case it will not be possible to equalize the heat transfer.

Heating systems for two wings

And yet, a system with a dead-end scheme is more often used. And all because the return line is longer and it is more difficult to assemble it. If your heating circuit is not very large, it is quite possible to adjust the heat transfer on each radiator and with a dead-end connection. If the circuit turns out to be large, but you don’t want to make a Tichelman loop, you can divide one large heating circuit into two smaller wings. There is a condition - for this there must be a technical possibility of such a network construction. In this case, in each circuit, after separation, it is necessary to install valves that will regulate the intensity of the coolant flow in each of the circuits. Without such valves, it is either very difficult or impossible to balance the system.

Different types of coolant circulation are demonstrated in the video, it also gives helpful tips on installation and selection of equipment for heating systems.

Connecting heating radiators with a two-pipe system

In a two-pipe system, any of the ways to connect radiators is implemented: diagonal (cross), one-sided and bottom. Most the best option- diagonal connection. In this case, the heat transfer from the heater can be in the region of 95-98% of the rated heat output of the device.

In spite of different meanings heat loss for each type of connection, they are all used, just in different situations. The bottom connection, although the most unproductive, is more common if the pipes are laid under the floor. In this case, it is the easiest to implement. It is possible to connect radiators with hidden laying according to other schemes, but then either large sections of pipes remain in sight, or they will need to be hidden in the wall.

Lateral connection is practiced, if necessary, with the number of sections not exceeding 15. In this case, there is almost no heat loss, but if the number of radiator sections is more than 15, a diagonal connection is already required, otherwise circulation and heat transfer will be insufficient.

Results

Although more materials are used to organize two-pipe circuits, they are becoming more popular due to the more reliable circuit. In addition, such a system is easier to compensate.

When designing a heating system, the question arises: “What kind of heating system will we make? One-pipe or two-pipe? In this article we will understand what these systems are and how they differ. To make things clear, let's start with definitions.

Definitions of one-pipe and two-pipe systems.

• Single-pipe - (abbreviated as OSO) is a system in which all heating devices (radiators, convectors, and so on, we will abbreviate them as software) are connected to the boiler in series using one pipe.
• Two-pipe - (abbreviated as DSO) is a system in which two pipes are supplied to each PO. According to one of them, the coolant is supplied from the boiler to the software (it is called the supply), and through the other, the cooled coolant is diverted back to the boiler (it is called the "return").

For the sake of completeness, we add two more definitions. According to these definitions, there is a division according to the principle of laying the supply line:

• With upper wiring - the hot coolant is first supplied from the boiler to the highest point of the system, and from there the coolant is supplied to the software.
• With lower wiring - the hot coolant is first discharged horizontally from the boiler, and then rises up the risers to the software.

Single pipe heating system.

As described above, in OCO all heating devices are connected in series. Passing through them, the coolant will cool down, so the “closer” the radiator is to the boiler, the hotter it will be. This fact must be taken into account when calculating the number of sections of heating radiators. The “farther” the radiator is from the boiler, the lower the temperature of the coolant will be in it and the more sections will be needed for heating. Lower wiring is possible only for houses with one floor and forced circulation in the system. With two or more floors, an upper piping is already needed.

There are two types of OSS:

1. OSO, in which heating devices are installed on the "bypass" (bypass jumper).
2. Flow OCO - all devices are connected in series without jumpers.

The second type is unpopular due to the difficulty of regulating the temperature in radiators, which is caused by the fact that it is impossible to use special fittings (thermostatic valves). Since when closing or reducing the flow through one radiator, the flow through the entire riser decreases. The main advantage of OCO is the lower cost of components and easier installation. The most popular version of a single-pipe system is Leningradka.

What is "Leningrad".

According to legend, this system got its name from the city where it was first applied. But of course, it is impossible to confirm this reliably, and I don’t really want to. So, "Leningradka" is a one-pipe heating system in which the software is installed on the "bypass". This allows you to regulate the temperature of individual radiators or convectors or turn them off altogether, if necessary. All the advantages and disadvantages of a single-pipe system are inherent in Leningrad, therefore, for distant radiators, it is necessary to increase the number of sections. Possible various options pipe layouts:

• Horizontal - the pipe lies in a horizontal plane and radiators are already installed on it.
• Vertical - the pipe runs vertically through the floors and radiators are connected to it.

OSO of the "Leningradka" type is best used for small private houses, where the number of floors does not exceed two. For large cottages with extended heating systems, such a "Leningrad" will not work.

An example of the implementation of "Leningradka"

Two-pipe heating system.

The main advantage of DSO is that the coolant comes to all software equally hot. This allows not to increase the number of sections on the "distant" radiators. That is, the most efficient use of heating devices occurs. The presence of two separate pipes for supply and return makes the installation of such a system more expensive. For such systems, both top and bottom piping and horizontal or vertical piping are possible.

In addition, DSO may differ in the direction of the coolant flow:

• Dead-end systems - water in the supply and return pipes flows in different directions.
• Flow systems - water in the supply and return pipes flows in the same direction.

Drawing from the book "Heating and water supply country house» Smirnova L.N.
You can use a two-pipe system for houses of any size, but it is most suitable for large cottages. Its use will allow you to change the flow rate of individual radiators, without affecting all the others. That is, it will be possible to use various room thermostats, which will create comfortable conditions for all residents.

Summary of the article.

The question of choosing the type of heating system depends on several factors:

• your budget
• area of ​​your home.
• Features internal device at home. For example, the number of floors
• The number of heating devices.

Most often, for small country houses (no more than 2 floors), a one-pipe system is better suited, and for large cottages (with a floor of 2 or more floors and a large length of pipelines), a two-pipe heating system will be more effective. Specific features of the implementation of a particular system are best discussed with a professional designer.