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Heating systems: single-pipe, double-pipe.

Nowadays, houses are installed 2 different systems heating: single-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

To understand what it looks like, look at the ring with the stone. In the heating system, the role of stone is played by the boiler. What about the ring, these are pipes of a specific diameter that run along the perimeter of the entire building. Radiators are connected to them. Water and sometimes antifreeze are often used as coolant. 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 at a lower temperature.

This circuit usually has natural coolant circulation. Hot water is first supplied to top floor. And then, passing through the radiators, the released part of the heat descends to the boiler, achieving complete 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 most a big plus is electrical independence, and the disadvantage is pipes that have a large diameter and the wiring is made at an angle.

Compared to two-pipe version, there are quite a lot of 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.

During use, difficulties may sometimes arise with circulation through the pipes, but this is easily solved by installing pump equipment. It produces proper circulation of coolant through the pipes.

A vertical single-pipe circuit is a popular example of wiring in apartment buildings.

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

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

Two pipe system

There are several types of it. The principle of operation is the same and is as follows. Hot water rises through the riser and flows from it into the radiators. And from them, through highways and return lines, it enters the pipeline, then into heating device. With this system, the radiator is served by two pipes simultaneously: return and supply, which is why it is called two-pipe. The 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 simple one 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 with a passing flow or dead-end. In the second movement warm water completely opposite to the direction of the already cooled one. This scheme is characterized by the length of the circulation rings, which depends on the distance of the heating device to the boiler. The circulation rings are of equal length in systems with one-way water movement, all devices and risers operate under equal conditions.

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

• the ability to distribute heat supply in different rooms;
• can be used on one floor;
• the shut-off systems for the return and supply risers are located in the basement - this significantly saves living space;
• minimizing heat loss.

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

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

One-pipe and two-pipe systems: comparison

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

For single-pipe systems there are 2 schemes. This is a flow and mixed scheme. The flow circuit has a peculiarity - the complete absence of jumpers between the supply and the outlet from the radiator. These schemes are almost never used when installing heating systems due to their impracticality. One battery breaks, and you need to turn off the riser, because there is no way to bypass the coolant. The advantage of single-pipe systems is the lower cost of building materials and ease of installation. Installation of single-pipe systems requires overhead wiring.

A two-pipe heating system can be used in any house: multi-story, single-story, etc. A two-pipe heating system is easy to implement with conventional circulation, since its configuration makes it possible to organize the circulation pressure; do not forget that the boiler must be installed below the level of the radiators. You can organize a heating system with forced circulation, just putting circulation pump into the circuit.

If it is possible to implement ring circuit, then you need to do it. A two-pipe system usually needs to be installed where there are difficulties with gas, power outages, etc. Enough for this system solid fuel boiler and larger diameter pipes. Brought firewood or coal, and you don’t have to worry about frost.

Methods for installing heating systems

Installation methods depend on the characteristics of the system.

Price installation work heating is determined by the characteristics of a particular project, and everything can be calculated only by specialists with experience in such work.

If you need to install heating with regular circulation, installing a system with a top spill will be effective. The water circulates through the pipes on its own. Systems with bottom spill do not provide efficient work without circulation pump.

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

Installation methods are also classified:

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

Heating installation with bottom pipe connections 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 installation methods is carried out completely depending on the diagram. You can install a two-pipe heating system or install single-pipe heating. In the second case, water flows through a pipeline through radiators, cooling along the way. The last radiator will be colder than the first. At two-pipe system There are 2 pipes 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 has an area of ​​over 100 square meters or 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 methods for installing autonomous heating:

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

A one-pipe system is cheaper. If you care about the quality of the heating system, there is no need to waste money on two-pipe wiring, since we get the ability to control the heat in the rooms.

When designing a heating system, the question arises: “What kind of heating system will we make? Single-pipe or double-pipe?” In this article we will figure out what these systems are and what is their difference. To make everything clear, let's start with definitions.

Definitions of one-pipe and two-pipe systems.

• Single-pipe - (abbreviated OCO) is a system in which all heating devices (radiators, convectors, and so on, abbreviated as software) are connected to the boiler in series using one pipe.
• Two-pipe - (abbreviated 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 boiler (it is called supply), and according to the other, the cooled coolant is discharged back to the boiler (it is called “return”).

To complete the description, we add two more definitions. According to these definitions, there is a division based on the principle of laying the supply line:

• With top 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 bottom wiring - the hot coolant is first removed horizontally from the boiler, and then rises up the risers to the software.

Single pipe heating system.

As described above, in OSO all heating devices are connected in series. Passing through them, the coolant will cool, 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 heating radiator sections. The “farther” the radiator is from the boiler, the lower the coolant temperature in it will be and the more sections will be needed for heating. Bottom distribution is possible only for houses with one floor and forced circulation in the system. With two or more floors, an upper pipe distribution is already required.

There are two types of OSO:

1. OSO, in which heating devices are installed on a “bypass” (bypass jumper).
2. Flow-through OSO - 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 the single-pipe system is the Leningradka.

What is "Leningradka"?

According to legend, this system got its name from the city where it was first used. But of course this cannot be reliably confirmed, and I don’t really want to. So, “Leningradka” is single pipe system heating, in which the software is installed on “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 the Leningrad system, so for distant radiators it is necessary to increase the number of sections. Possible various options pipe routing:

• 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 type “Leningradka” 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” is not suitable.

An example of the implementation of "Leningradka"

Two-pipe heating system.

The main advantage of DSO is that the coolant arrives to all software equally hot. This allows you to avoid increasing the number of sections on “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 this type of system, both upper and lower pipe routing and horizontal or vertical piping are possible.

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

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

Drawing from the book “Heating and water supply” country house» Smirnova L.N.
The two-pipe system can be used 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 others. That is, it will be possible to use various room thermostats, which will allow you to 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
• The area of ​​your home.
• Features internal structure Houses. For example, number of floors
• Number of heating devices.

Most often, for small country houses(no more than 2 floors) a single-pipe system is better suited, and for large cottages (with 2 or more floors and a long length of pipelines) a two-pipe heating system will be more effective. It is better to discuss specific features of the implementation of a particular system with a professional designer.

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All heating systems today are divided into two main types: single-pipe and two-pipe heating systems. Each type has its own characteristics and features, but two-pipe heating systems have become the most popular. Sometimes people wonder, single-pipe or two-pipe heating system - what to choose?

Single pipe heating system

Such a heating system is a closed loop, which is interrupted by the boiler. Installing such a system involves installing a pipeline throughout all rooms in the house. Radiators are connected to the pipes, and a coolant is introduced into the system (its role is most often played by distilled water), which ensures heat transfer to each room. The operating principle of such a heating system is based on the difference in water temperatures at the beginning of the cycle and during the reverse movement, that is, the water that has passed through the entire circuit returns to the boiler cooled.

Most often, this design uses natural coolant circulation. To do this, the heated water first rises to the maximum possible height, after which it gradually descends through the pipes, cooling as it moves.

The following can be connected to a one-pipe heating system:

• thermostatic valves;
• radiator regulators;
• balancing valves;
• Ball Valves.

These mechanisms allow for finer tuning of the heating system for high-quality and uniform heating of the entire building.

Characteristic features of a single-pipe heating system

The most important advantage of a single-pipe heating system with natural circulation is that there is no need for electricity. Instead, a significant disadvantage appears, which is expressed in the rather large diameter of the pipes and the need to create a constant pipeline slope.

Advantages of single-pipe heating over two-pipe heating:

1. Pipes can be connected to " heated floors» or heating radiators.
2. Such a system can be installed in any room, regardless of the layout.
3. The closed circuit allows the entire building to be heated as a single piece.
4. Such a system is much cheaper because it requires much less materials.

When using a single-pipe system, the problem of “stagnation” of liquid in the pipeline very often arises. This problem is solved using a pump that cuts into the system immediately in front of the boiler, at the very end of the return line.

IN multi-storey buildings Most often, a vertical single-pipe heating system is used, while a horizontal one is better suited for compact one-story houses. In this case, all heating elements are located at the same height, which gives rise to the following problem: water that has cooled in one radiator approaches the next one already cold. Such a system is much cheaper, but also has significant disadvantages.

Radiators in such a system are not controlled: a horizontal heating system does not imply free adjustment of each heating device. If necessary, bypasses can be built into such a system, which make it possible to bypass the coolant bypassing a separate radiator, but such a device will make the system more expensive. Turning off the radiator leads to the fact that the room begins to be heated due to the heat coming from the pipes or riser.

In addition, for effective use For this system, it is recommended to use heating elements of different sizes. To equalize heat transfer, the first radiator installed should be quite small, and the last one should be much larger.

Two-pipe heating system

Despite the presence of a number of modifications, the two-pipe heating system operates on the same principle. The heated liquid rises through the riser, from where it enters the radiators. But if one pipeline circuit goes to the radiators, then the cooled liquid is removed using the second circuit. This is the point. Water enters such a system directly from the water supply. For the system to function properly, it needs expansion tank, which can be simple or complex.

The simple one contains a container to which two pipes are connected. One of them is a riser designed to supply water, and the second pipe allows you to eliminate excess liquid (read: ""). IN complex design Four pipes are installed, two of which are responsible for the circulation of liquid, and the other two monitor the water level in the system and the tank itself.

Two-pipe heating systems work well in conjunction with a pump. Circulation can be carried out either with a passing flow or with a dead-end method. In the latter case, the heated and cooled liquid move in the opposite direction. Both circulation circuits have the same length, so all radiators provide equal heat transfer.

A two-pipe heating system outperforms a single-pipe heating system in a number of parameters:

1. Possibility of precise control over the uniformity of heat supply in different rooms.
2. The system is well suited for heating single-story buildings.
3. Riser locking systems can be located in the basement, thus saving on usable area building.
4. There are practically no heat losses in this system.

The disadvantages of a two-pipe system include its high cost: the number of pipes will double compared to a single-pipe analogue. In addition, air will periodically appear in the supply line, and to eliminate it, it is necessary to install taps.

A horizontal closed two-pipe circuit can be equipped with upper and lower wiring. Using lower wiring allows you to add new heating devices to the system gradually, as new floors are built (more details: " "). The vertical system is well suited for houses with variable number of storeys. In any case, a two-pipe heating system will cost more than a single-pipe one, but its use will provide much greater comfort and convenience.

Single-pipe or two-pipe heating system: advantages and disadvantages

In single-pipe systems there are no return risers. The movement of the coolant in this case is ensured by natural circulation or a pump. The cooled liquid enters bottom part system, and along the way it is mixed with coolant from the supply riser. Closed circuit ensures constant circulation of fluid in the system. As water passes through the pipeline, it cools, so the surface area of ​​the heating device located further from the boiler must be larger in order to increase heat transfer.

Single-pipe heating systems can be built according to two schemes: flow-through and mixed (read: ""). The flow circuit completely lacks any workarounds, so if one heating element fails, the entire system has to be turned off. This option is currently practically not used, since it is extremely irrational. However, single-pipe systems have a low cost due to a minimum of materials and simple installation. When installing such systems, top wiring is required.

Installation of heating systems

Single-pipe and two-pipe heating systems are installed differently, and the installation of a suitable system will depend on the selected parameters, and any specialist can calculate the cost of installation. If you select for installation natural circulation, then it would be advisable to install the upper wiring, and if you have a pump and there are no problems with the power supply, you can use the lower one.

Additionally, installation methods heating systems can be classified by:

• type of wiring;
• number of risers;
• type of pipe connection.

Bottom connection pipes is the most common. Usage this method allows you to run pipes under the floor or baseboard, which has a positive effect on the interior of the premises (more details: " ").

The main classification of heating installation methods is still based on the chosen scheme. Single-pipe and two-pipe heating systems have a lot in common, but the difference between them is too great to put them on the same page. The advantages of single-pipe heating are obvious: low cost and ease of operation. But this system also has enough disadvantages, and the most important of them is that if it is too large area at home (more than 100 sq.m.) or if there is a second floor, a single-pipe scheme simply will not justify itself. In such cases, it will be much more profitable to opt for a two-pipe heating system.

Last option It also gives you the opportunity to choose suitable way radiator installations:

• sequentially;
• parallel;
• diagonally;
• on the side.

You can see the installation methods in detail in the photo.

The classification of installation methods can also be carried out according to the location of the risers:

• heating with horizontal wiring;
• heating with vertical wiring;
• heating without risers.

Conclusion

The single-pipe system is cheaper and simpler. The two-pipe system is more convenient and reliable. Regardless of whether a single-pipe or two-pipe heating system is installed in the house, heating of the premises will still occur. The final choice depends on the homeowner, but still the two-pipe system has a large number of advantages, and its performance characteristics indicate that using such a scheme in your home will be more profitable and convenient.

The video shows a single-pipe and two-pipe heating system for comparison:

It is quite difficult to give an unambiguous answer to the question which heating system is better: one-pipe or two-pipe, because each system is suitable for various situations. In this article, we will analyze the advantages and disadvantages of each system and answer the question in what situations one or another scheme should be used.

Which systems will be compared?

It should be immediately noted that for comparison we will take equally well-functioning systems, i.e. single-pipe and two-pipe schemes, in which all heating devices heat up to approximately the same temperature and are capable of maintaining the required temperature in a single private house. Those. we will not consider a single-pipe system in which, for example, the first radiator heats up to 60°C, and the last one to 40°C, because Such indicators indicate that the system is not working correctly.

Therefore, there is no point in considering such a “non-working” system, even though such a single-pipe system will have some advantages over a similar two-pipe system, primarily regarding cost. Such a one-pipe initial stage will be cheaper, but in the future this cheapness will lead to unsatisfactory heating of the latest radiators. That is why we consider only correctly operating systems that will delight the owners of the house with equally heated radiators in all rooms.

Comparable parameters

The following parameters will determine which heating system is better, single-pipe or double-pipe, and in what situations one or another system should be used.

Price

A single-pipe heating system is more expensive. High price consists of two main factors:

• The need to increase the number of sections in each radiator next in the direction of coolant circulation. A single-pipe scheme consists of one supply pipeline through which the coolant passes through the entire heating circuit, sequentially entering each heating device. From each radiator, the coolant leaves several degrees colder than when entering the radiator (part of the heat, about 10°C, is transferred to the room). Therefore, if a coolant with a temperature of 60°C enters the first radiator, then a coolant with a temperature of 50°C leaves the radiator, after which the 2 flows are mixed in the supply line, as a result of which the coolant enters the second heating device with a temperature of about 55°C . Thus, after each radiator there will be a loss of about 5°C. It is to compensate for these losses that it is necessary to increase the number of sections for each subsequent heating device.

In a two-pipe scheme there is no need to increase the number radiator sections, because Each device receives coolant at almost the same temperature. The two-pipe contains both a supply and a return line, to which each heating device is simultaneously connected. Having passed through the radiator, the coolant immediately enters the return line and is sent to the boiler for further heating. Thus, each radiator receives almost the same temperature (heat losses are present, but they are very insignificant).

Note! Best use single-pipe schemes are small heating systems where there are no more than 5 radiators. With such a number of heating devices, the coolant, sequentially passing through all 5 radiators, does not lose heat in such critical quantities as in single-pipe systems with big amount heating devices.

• The need to use an enlarged supply pipeline. If the supply pipeline is too “thin”, this will lead to the fact that many radiators simply do not receive the heated coolant. Pipe large diameter allows you to deliver heated coolant to as many heating devices as possible. The thicker the supply pipe, the fewer sections need to be added to each radiator.

Thus, an increase in the number of radiator sections and an increase in the diameter of the supply line makes a single-pipe system more expensive in comparison with a similar two-pipe system.

Economical

The two-pipe scheme is more economical in operation. As noted above, in order to achieve uniform heating of all radiators in single-pipe scheme the use of “thick” feed is required, as well as an increase in the number of sections in the radiators. All this increases the volume of coolant, and the more coolant in the system, the more fuel is required to heat it. Therefore, to the question which heating system is better, one-pipe or two-pipe in terms of efficiency, the answer will be in favor of the two-pipe system.

Installation process

Single-pipe system is more complex in calculations, because you should correctly calculate how many sections should be enlarged for each subsequent heating device. Besides, Special attention It is necessary to pay attention to the calculation of the supply line and radiator connections.

Conclusion

It is most advisable to use a two-pipe scheme in extended heating systems with a large number of heating devices. This is an economical, efficient, easy-to-install system.

On the contrary, the single-pipe scheme is most suitable for small systems, in which there is a small number of heating devices (no more than 5 radiators).

Video

Almost every owner of a private home faces the question:
“Should I choose a two-pipe or one-pipe heating system?”

We will describe the main pros and cons of both systems, and then give our recommendations.

Single pipe heating system - a system in which the function of supplying and removing coolant is played by one pipe.

Advantages of a one-pipe system:

• To supply coolant, one pipe is used instead of two. This is a direct saving of your money on the cost of pipes, fittings and installation work.
• virtually does not require any adjustment of individual branches and risers.
• has a smaller coolant volume. In the case of using antifreeze, this is again a direct saving of your money.
• increased hydraulic stability of this system.
• if it is necessary to drain the system, this process speeds up and does not lead to an excessive volume of water in drain hole, because has a smaller coolant volume.
  
• installation time is shorter than in a two-pipe system.
• in the presence of a ready-made (calculated) project with executive diagrams and specified diameters does not require highly qualified installers.

Disadvantages of a one-pipe system:

• increased vulnerability to defrosting of the entire system. Freezing of the system in at least one place makes the circuit inoperable.
• as it moves away from the boiler, it requires an increased size of heating devices. Due to the fact that not only hot water(directly from the boiler), but also cooled down (from the heating devices), increasingly cooled water comes to the input of each subsequent radiator. But heat loss remains the same. To compensate for them, more sections are required. This factor directly negates and even detracts from the initial apparent gain in the cost of the material.

D double pipe heating system - a system in which two pipes are used to supply and remove coolant.

Advantages of a two-pipe system:

• At the inlet of each radiator, a coolant arrives at a temperature that is actually equal to the boiler temperature (heat losses along the way, if the pipes are insulated according to standards, are insignificant). This means a smaller size of the heating device and, therefore, saving money.
• less vulnerable to defrosting the entire system (see explanation at the end of the article).
• allows you to quickly find shortcomings and errors made during the installation process, and correct them without less serious consequences (than in the case of a single-pipe system).
• less sensitive to errors made at the design stage.

Disadvantages of a two-pipe system.

Such a system has practically no disadvantages, with the exception of the cost and installation time, which are of course higher than in the case of a single-pipe system, but these disadvantages are more than compensated for by the convenience, quality and reliability of operation of this system.

After considering the pros and cons of the systems described, you can make your decision in favor of one option or another.

With all our knowledge of the matter, we strongly recommend choosing a two-pipe system.

In addition to those mentioned above positive features this scheme, we present one more consideration as a substantiation of our recommendation.

Imagine that you have a choice: you need to choose two electric garlands. In one garland the light bulbs are connected in series, and in the other in parallel. The criterion you follow is reliability, ease of operation and repair. Which one will you choose?

Let's say you take one where the bulbs are connected in series. What happens when one light bulb burns out? The chain breaks. The entire garland stops working.

What can you say about searching for a burnt-out light bulb in such a garland if you don’t have special equipment?

Anyone who has been looking for such a light bulb knows how long it takes.

What does this example have to do with the heating system? The most direct.

We said above that a single-pipe system is most vulnerable to defrosting of the entire system. All heating devices “sit” on one pipe. And although technically it would be incorrect to say that they are connected in series (unless, of course, this is a type of single-pipe system - a flow-through system). Still, think about what would happen if at least 1 cm or 0.5 cm of water in this pipe froze (thresholds are especially vulnerable entrance doors or leaks in brick seams, especially when there is no insulation on the pipes or walls)?

Right. The whole system would come to a standstill. And gradually she would freeze all over.

What about finding a frozen section of pipe? Believe me - it is almost impossible!

Now let’s take a garland with parallel-connected light bulbs. What happens when one or two burn out?

Others continue to burn. Is it easy to find the light bulb that has burned out? Certainly. Everyone is on fire, but she is not!

The same applies to a two-pipe system. If it happens that the pipe going to one radiator freezes, this does not mean that the others will stop working.

Is it easy to find the radiator and, accordingly, the place where the accident occurred? Yes. You just need to touch it with your hand and everything will become clear.

Isn't this a powerful factor in favor of choice? two-pipe system?

Wondering: “Should I choose a two-pipe or one-pipe heating system?” Do not hesitate to choose a two-pipe heating system and you will never regret your choice!