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Heating systems: single-pipe, double-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

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 supplied to the top floor first. 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 biggest advantage is electrical independence, and the disadvantage is the pipes, which have a large diameter and are routed at an angle.

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.

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 the 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.

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 located 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, simply by placing a circulation pump in the circuit.

If it is possible to implement a ring circuit, then we need to do it. 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 sufficient. 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 a single-pipe heating system. In the second case, water flows through a pipeline through 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 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 your heating system, there is no need to waste money on two-pipe wiring, because we get the ability to control heat in the rooms.

Two-pipe heating system

There are only two types of heating systems: single-pipe and double-pipe. In private homes, they try to install the most efficient heating system. It is very important not to go cheap when trying to reduce the cost of purchasing and installing a heating system. Providing heat to a home is a lot of work, and so as not to have to install the system again, it is better to understand it thoroughly and make “reasonable” savings. And in order to draw a conclusion about which system is better, it is necessary to understand the operating principle of each of them. Having studied the advantages and disadvantages of both systems, both from the technical and material side, it becomes clear how to do optimal choice.

Single pipe heating system

It works on the principle: through one main pipe (riser), the coolant rises to the top floor of the house (in the case multi-storey building); All heating devices are connected in series to the downward line. In this case, all upper floors will be heated more intensely than the lower ones. A well-common practice in Soviet-built multi-story buildings, when it is very hot on the upper floors and cold on the lower floors. Private houses most often have 2-3 floors, so single-pipe heating does not threaten a large temperature contrast on different floors. In a one-story building, heating is almost uniform.

Advantages of a single-pipe heating system: hydrodynamic stability, ease of design and installation, low costs of materials and funds, since the installation of only one coolant line is required. Increased water pressure will ensure normal natural circulation. The use of antifreeze increases the efficiency of the system. And, although this is not the best example of a heating system, it has become very widespread in our country due to the high savings in material.

Disadvantages of a single-pipe heating system: complex thermal and hydraulic calculations of the network;
- it is difficult to eliminate errors in the calculations of heating devices;
- interdependence of the operation of all network elements;
- high hydrodynamic resistance;
- limited number of heating devices on one riser;
- inability to regulate the flow of coolant into individual heating devices;
- high heat loss.

Improvement of single-pipe heating systems
Developed technical solution, allowing you to regulate the operation of individual heating devices connected to one pipe. Special closing sections - bypasses - are connected to the network. The bypass is a jumper in the form of a piece of pipe that connects the direct pipe of the heating radiator and the return pipe. It is equipped with taps or valves. The bypass makes it possible to connect automatic thermostats to the radiator. This allows you to regulate the temperature of each battery and, if necessary, shut off the coolant supply to any individual heating device. Thanks to this, it is possible to repair and replace individual devices without completely shutting down the entire heating system. Correctly connecting the bypass makes it possible to redirect the flow of coolant through the riser, bypassing the element being replaced or repaired. For quality installation For such devices, it is better to invite a specialist.


Vertical and horizontal riser diagram
According to the installation scheme, single-pipe heating can be horizontal or vertical. A vertical riser is the connection of all heating devices in series from top to bottom. If the batteries are connected in series to each other throughout the entire floor, this is a horizontal riser. The disadvantage of both connections is air pockets that occur in heating radiators and pipes due to accumulated air.


A heating system with one main riser is equipped with heating devices that have improved reliability characteristics. All devices of a one-pipe system are designed for high temperature and must withstand high blood pressure.

Installation technology of a single-pipe heating system
1. Installation of the boiler in the selected location. It is better to use the services of a specialist from the service center if the boiler is under warranty.
2. Installation of the main pipeline. If an improved system is being installed, then it is mandatory to install tees at the connection points of radiators and bypasses. For heating systems with natural circulation when installing pipes
create a slope of 3 - 5o per meter of length, for a system with forced circulation of coolant - 1 cm per meter of length.
3. Installation of a circulation pump. The circulation pump is designed for temperatures up to 60°C, so it is installed in that part of the system where the most low temperature, that is, at the entrance of the return pipe to the boiler. The pump operates from the mains power supply.
4. Installation of the expansion tank. Open expansion tank installed at the highest point of the system, closed - often next to the boiler.
5. Installation of radiators. They mark out places for installing radiators and secure them with brackets. At the same time, they comply with the recommendations of device manufacturers regarding maintaining distances from walls, window sills, and floors.
6. The radiators are connected according to the chosen scheme, installing Mayevsky valves (for venting the radiators), shut-off valves, and plugs.
7. The system is pressure tested (air or water is supplied to the system under pressure to check the quality of connection of all elements of the system). Only after this, coolant is poured into the heating system and a test run of the system is performed, and adjustment elements are adjusted.

Two-pipe heating system

In a two-pipe heating system, the heated coolant circulates from the heater to the radiators and back. This system is distinguished by the presence of two pipeline branches. Along one branch, the hot coolant is transported and distributed, and along the second, the cooled liquid from the radiator is returned to the boiler.

Two-pipe heating systems, like single-pipe heating systems, are divided into open and closed depending on the type of expansion tank. In modern two-pipe closed heating systems, membrane-type expansion tanks are used. The systems are officially recognized as the most environmentally friendly and safe.

According to the method of connecting elements in a two-pipe heating system, they are distinguished: vertical and horizontal systems.

IN vertical system all radiators are connected to a vertical riser. Such a system allows multi-storey building connect each floor separately to the riser. With this connection, there are no air pockets during operation. But the cost of this connection is slightly higher.


Double-pipe horizontal heating system is mainly used in one-story houses with large area. In this system, heating devices are connected to a horizontal pipeline. It is better to install risers for wiring connections of heating elements on staircase or in the hallway. Air jams are released using Mayevsky taps.

Horizontal heating system can be with bottom and top wiring. If the wiring is bottom, then the “hot” pipeline runs in the lower part of the building: under the floor, in the basement. In this case, the return line is laid even lower. To improve coolant circulation, the boiler is deepened so that all radiators are above it. The return line is located even lower. The upper air line, which must be included in the circuit, serves to remove air from the network. If the distribution is top, then the “hot” pipeline runs along the top of the building. The place for laying the pipeline is usually an insulated attic. At good insulation pipes, heat loss is minimal. At flat roof this design is unacceptable.

Advantages of a two-pipe heating system:
- even at the design stage, it is provided for the installation of automatic thermostats for heating radiators and, therefore, the ability to regulate the temperature in each room;
- pipes throughout the premises are routed through a special collector system, which ensures independent operation of the circuit devices;
- in other words, the circuit elements in a two-pipe system are connected in parallel, unlike a one-pipe system, where the connection is sequential;
- batteries can be inserted into this system even after assembling the main line, which is impossible with a single-pipe system;
- a two-pipe heating system can be easily extended in the vertical and horizontal directions (if you have to complete the house, then the heating system does not need to be changed).


For this system, there is no need to increase the number of sections in the radiators in order to increase the volume of coolants. Errors made at the design stage are easily eliminated. The system is less vulnerable to defrosting.

Disadvantages of a two-pipe heating system:
- more complex circuit connections;
- higher project price (much more pipes are required);
- more labor-intensive installation.
But these shortcomings are very well compensated by winter time when maximum heat accumulation occurs in the house.

Installation of a two-pipe heating system
I. Installation of a heating system with upper horizontal wiring
1. An angle fitting is mounted to the pipe leaving the boiler, which turns the pipe upward.
2. Using tees and angles, mount the top line. Moreover, the tees are attached above the batteries.
3. When the top line is installed, the tees are connected to the top branch pipe of the battery, and a shut-off valve is installed at the junction point.
4. Then install the lower branch of the outlet pipeline. It goes around the perimeter of the house and collects all the pipes coming from the lowest point of the radiators. Typically this branch is mounted at the base level.
5. The free end of the outlet pipe is mounted into the receiving pipe of the boiler; if necessary, a circulation pump is installed in front of the inlet.

Mounted in a similar way closed system with constant pressure maintained by a pressure pump and an open heating system with an open expansion tank at its highest point.

The main inconvenience of a two-pipe heating system with overhead wiring is the installation of an expansion tank outside warm room on the ceiling. A heating system with overhead wiring also does not allow for the selection of hot water for technical needs, as well as for combining the expansion tank with the supply tank of the water supply system at home.

II. Installation of a heating system with lower horizontal piping
The bottom-piping system replaced the two-pipe heating system with top-piping. This made it possible to place the expansion tank open type in a warm room and easily accessible place. It also became possible to save some pipes by combining the expansion tank and the supply tank of the house water supply system. The compatibility of the two tanks eliminated the need to control the coolant level and made it possible, if necessary, to use hot water directly from the heating system.
In such a scheme, the outlet line remains at the same level, and the supply line is lowered to the level of the outlet line. This improves aesthetics and reduces pipe consumption. But it only works in systems with forced circulation.

Installation sequence:
1. Downward-facing corner fittings are installed on the boiler pipes.
2. At floor level, two lines of pipes are installed along the walls. One line is connected to the supply output of the boiler, and the second to the receiving output.
3. Tees are installed under each battery, connecting the batteries to the pipeline.
4. An expansion tank is installed at the top point of the supply pipe.
5. As in the case of the upper distribution, the free end of the outlet pipe is connected to circulation pump, and the pump - to the inlet of the heating tank.

Maintenance of a two-pipe heating system
For high-quality maintenance of the heating system, it is necessary to implement a whole range of measures, including adjustment, balancing and tuning of the two-pipe heating system. To adjust and balance the system, special pipes are used, located at the highest and lowest points of the heat pipe. Air is released through the upper pipe, and water is supplied or drained through the lower pipe. Using special taps, excess air in the batteries is released. To regulate the pressure in the system, a special container is used, into which air is pumped using a conventional pump. Special regulators, reducing the pressure into a specific battery, adjust the two-pipe heating system. The consequence of pressure redistribution is the equalization of temperatures between the first and last batteries.

All existing heating systems can be divided into two groups:

• single-pipe;
• two-pipe.

To answer the question: which heating system is better, one-pipe or two-pipe, it is necessary to understand on what principle each of them works.

This will clearly indicate the advantages and disadvantages of each of them, and will also help make the most optimal choice, both technically and in terms of the necessary means to understand single-pipe or two-pipe system heating is more suitable.

Videos about the types of heating systems can be easily found on the World Wide Web.

Advantages of a single-pipe heating system

• fewer materials and tools;
• hydrodynamic stability;
• less labor intensive design and installation;
• absence special requirements to infrastructure.

But with all these advantages, we can say with complete confidence that a single-pipe system is far from the most best scheme, according to which heating can be realized. Still, the main reason why the single-pipe system has become widespread in our country is the undeniable saving of material.

Single-pipe heating system: operating principle

Such a system has one riser (main pipe). Through it, heated water (or any other coolant) rises to the upper floors of the building (if it is a multi-story building).

All heating devices (units for heat transfer - batteries or radiators) are connected in series to the downward line.

Modernization of single-pipe heating systems

A technical solution has been developed that makes it possible to regulate the operation of each individual heating device.

It consists of connecting special closing sections (bypasses), which make it possible to integrate radiator automatic thermostats into heating systems. What other benefits are possible when installing bypasses? We'll talk about this in more detail later.

The main advantage of this modernization is that in this case it becomes possible to regulate the heating temperature of each battery or radiator. In addition, you can completely shut off the coolant supply to the device.

Thanks to this, such a heating device can be repaired or replaced without shutting down the entire system.

The bypass is a bypass pipe equipped with valves or taps. At correct connection such fittings to the system, it will allow you to redirect the flow of water along the riser, bypassing the heating device being repaired or replaced.

It is not difficult to understand that the task of installing such devices into a system with your own hands is hardly possible to solve, even if there is a detailed instructions. In this case, it is impossible to do without the participation of a specialist.

A heating system with one main riser must be equipped with heating devices that have improved reliability characteristics. Any devices in a one-pipe system must withstand high blood pressure and high temperature.

Vertical and horizontal riser diagram

According to the implementation scheme itself, single-stack heating comes in two types:

• vertical;
• horizontal.

If heating appliances are connected from the top floor to the bottom, this is a vertical riser. If the batteries are connected in series to each other throughout all rooms of a building floor, this is a horizontal riser.

Disadvantages of a single-pipe heating system

• complexity of thermal and hydraulic calculations of the network;
• difficulty in eliminating errors in the calculations of heating devices;
• interdependence of the operating characteristics of all devices on the network;
• increased hydrodynamic resistance;
• limiting the number of heating devices on one riser;
• inability to regulate batteries and radiators with regulators (pictured below)

Important!
If you connect more than ten heating devices (for example, eleven) to a vertical riser, then on the first radiator in the network the water temperature will be about 105 ° C, and on the last one - 45 ° C.

Single-stack heating in individual construction

If heating with one main riser is installed in a one-story building, then it will be possible to get rid of at least one significant drawback of such a scheme - uneven heating.

If such heating is implemented in a multi-story building, then the upper floors will be heated much more intensely than the lower floors. This will lead to a situation where it is cold on the first floors of the house, and hot on the upper floors.

A private house (mansion, cottage) is rarely more than two or three floors high. Therefore, installing heating, the scheme of which was described above, does not threaten that the temperature on the upper floors will be much higher than on the lower floors.

Two-pipe heating system: advantages and disadvantages

Advantages of a two-pipe manifold system

• It becomes possible to install automatic thermostats for radiators or radiators. In this case, such devices are provided at the system design stage;
• Pipes according to this scheme are distributed throughout the premises through a special collector system. If one of the elements in the system fails or begins to operate unstably, this does not in any way affect the operation of the remaining devices in the circuit;
• In other words, with a two-pipe system, the elements of the thermal circuit are connected in parallel, unlike in series - with a single-pipe system.

The main disadvantages of a two-pipe heating system

• heating becomes more complex according to the connection diagram;
• the price of the project requires more funds;
• installation of the circuit is more labor-intensive.

Where are two-pipe heating systems used:

• in individual housing construction;
• in so-called “elite” housing projects;
• high-rise buildings (with overhead wiring)

Important!
When designing buildings with more than 9-10 storeys, it is better to use either a single-pipe system with horizontal floor-to-floor wiring, or a two-pipe system with upper vertical wiring.
This will ensure better circulation.

Advantages of two-pipe collector heating

• reduced hydrodynamic resistance;
• possibility of independent temperature control in each room.

Before starting, the collector heating system requires careful preset. For correct installation, installation and operation of a two-pipe system requires the availability of appropriate infrastructure.

Options for wiring diagrams of a two-pipe system

Upper wiring

A system with top wiring is suitable for natural circulation (without the use of pumps) (). It has lower hydrodynamic resistance. In this case, the upper supply main pipe is partially cooled. Due to this, additional coolant circulation pressure is generated.

Bottom wiring

In a system with bottom wiring, both the supply and discharge pipes are located nearby.

There are such modifications of the lower wiring:

So, is the heating system one-pipe or two-pipe? In each case it is necessary to have preliminary calculations and the project (see), on the basis of which both heating devices and the main pipes themselves will be selected (see). Final decision only for you.

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. The high cost 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 circuit 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 of 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 a large number of 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 a single-pipe circuit, it is necessary to use a “thick” feed, 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 this, 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, a single-pipe scheme is most suitable for small systems in which there are 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 volume of coolant. 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 volume of coolant.
  
• installation time is shorter than in a two-pipe system.
• if there is a ready-made (calculated) project with as-built diagrams and specified diameters, it 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!