Two-pipe horizontal heating system with upper wiring. What to choose: one-pipe or two-pipe heating system. Differences in horizontal wiring by floor

For each private household, the installation of a heating system is considered one of the fundamental issues. Modern construction technologies offer two options: a single-pipe or two-pipe system.

It is important not to sell cheap here, trying to reduce the cost of installation and purchase of materials. And only having understood the principle of operation of these systems, with their advantages and disadvantages, you can make the right choice.

The operation of a single-pipe heating system occurs according to fairly simple principles. There is only one closed pipeline through which the coolant circulates. Passing through the boiler, the carrier heats up, and passing through the radiators, it imparts this heat to them, after which, cooled, it again enters the boiler.

The riser in a single-pipe system is also one, and its location depends on the type of building. So, for one-story private houses, the horizontal scheme is best suited, while for multi-storey buildings - vertical.

Note! A hydraulic pump may be required to pump the coolant through vertical risers.

To improve the efficiency of a one-pipe system, some improvements can be made. For example, install bypasses - special elements, which are pipe sections connecting the direct and return pipes of the radiator.

This solution makes it possible to connect thermostats to the radiator that can control the temperature of each heating element, or completely disconnect them from the system. Another plus of bypasses is that they allow you to replace or repair individual heating elements without shutting down the entire system.

Mounting Features

In order for the heating system to give warmth to the owners of the house for many years, during the installation process it is worth adhering to the following sequence of actions:

• According to the developed project, the boiler is being installed.
• The pipeline is being installed. In places where the project provides for the installation of radiators and bypasses, tees are installed.
• If the system works according to the principle of natural circulation, it is necessary to provide a slope of 3-5 cm for each meter of length. For a circuit with forced circulation, a slope of 1 cm per meter of length will suffice.
• For systems with forced circulation, a circulation pump is installed. It should be borne in mind that the device is not designed for operation at high temperatures, so it would be better to install it near the return pipe inlet to the boiler. In addition, the pump must be connected to the electrical network.
• Installing an expansion tank. An open tank should be located at the highest point of the system, a closed one - in any convenient place (most often it is mounted near the boiler).
• Installation of heating radiators. They weigh a lot (especially when filled with water), so they are fixed with special brackets, which, as a rule, come with the kit. Installation is most often carried out under window openings.
• Additional devices are being installed - Mayevsky cranes, plugs, blocking devices.
• The final stage is testing the finished system, for which water or air is supplied under pressure. If the tests do not reveal problem areas, the system is ready for operation.

You can decide which heating system is better, one-pipe or two-pipe, after analyzing the design features, the pros and cons of each option. In any case, it is necessary to make a verdict at the design stage of construction. is a rather complex structure. It is difficult, and sometimes impossible, to redo it after finishing work. Consider the difference between two different approaches to arranging the heating of buildings using boilers, batteries and piping.

This option is used in cases where it is necessary to carry out communications quickly and at minimal cost.

It is used in residential, private and industrial construction. A feature of this solution is the absence of a return water supply line. Batteries are connected in series, assembly is carried out in a short time and does not require complex preliminary calculations.

How does a single pipe line work?

In such designs, the coolant is supplied to the top point and flows down, successively passing through the heating elements. When arranging a multi-storey building, it is practiced to install an intermediate pump that creates the necessary pressure in the supply pipe to push hot water through a closed circuit.

Given the low height of the house and a limited number of heat consumers, water circulation is sufficiently efficient.

Vertical and horizontal layouts

The construction of a single-pipe line is carried out in vertical and horizontal orientation. Vertical wiring is installed in buildings with two or more floors. The coolant is supplied to the radiators, starting from the top one. A horizontal heating main is most often used for arranging single-level buildings - houses, summer cottages, warehouses, offices and other commercial facilities.

The piping layout assumes a horizontal arrangement of the riser with its serial supply to the batteries.

Pros and cons

The single-pipe design of the heating main has the following advantages:

• Installation is carried out quickly, which is important given the modern requirements of the pace of construction. In addition, the appearance of a single-pipe collector several meters high compares favorably with a complex system of two lines.
• Small budget. The cost calculation shows that the construction requires a minimum number of pipes, fittings and fittings.
• If consumers are installed on the bypass, then it becomes possible to regulate the heat balance separately in each room.
• The use of modern locking devices makes it possible to modernize and improve the highway. This allows you to replace radiators, insert devices, and other improvements without a long shutdown of the system and draining water from it.

This design also has its drawbacks:

• The sequential arrangement of the batteries does not exclude the possibility of adjusting the heating temperature in them separately. This entails cooling all other radiators.
• Limited number of batteries per line. It is not advisable to set them more than 10, since at the lower levels the temperature will be below the permissible level.
• The need to install a pump. This event requires additional financial investments. The power plant can cause water hammer and damage to lines.
• In a private house, you will need to install an expansion tank with a valve to bleed air. And this requires a place and carrying out warming measures.

Two-pipe heating system

This design has a more complex device, but also differs in efficiency and functionality.

Invested funds are compensated by comfort for people, ease of maintenance and modernization.

Principle of operation and scheme of work

They are two risers and radiators located between them, underfloor heating and other heat consumers. The supply is carried out along one line, the cooled liquid returns to the boiler along the return branch. That is why such structures are called two-pipe.

Classification: bottom and top wiring

There are two types of systems according to the location of the highways. The choice is made based on the features of the structure and the possibility of allocating space for additional equipment. Two-pipe communications are classified into vertical for high-rise buildings and horizontal for one-story buildings.

According to the location of the strapping, the systems are divided into upper and lower, regardless of where the radiators are installed.

With the upper option, the entire interchange is arranged in the attic or technical floor of the building. At the same time, an expansion tank is installed, which is carefully insulated. After the boiler, a pump is installed that supplies the coolant to the upper level.

In the case of the lower wiring, the hot riser is located above the return. The heating boiler is installed in the basement or on the ground floor with a recess below the floor. An upper air line is connected to the pipeline to bleed air from the radiators.

Advantages and disadvantages

The main advantages of the two-pipe design are as follows:

• Simultaneous transfer of the coolant to consumers allows you to adjust the temperature individually in each room. If necessary, the radiators are completely blocked if the room is not used for a long time.
• The ability to remove individual devices for repair or replacement without turning off the heat supply to the remaining batteries. For this, ball valves are used, with the help of which the flow of water is blocked at the inlet and outlet of the radiator.
• There is no need to install a centrifugal pump. Water rises from the boiler upward due to the difference in temperature at the inlet and outlet.
• The choice of a passing or dead-end design option. This makes it possible to balance the distribution of heat without constant adjustments and adjustments.

Design flaws are:

• Use in the construction of more pipes and components. This leads to the complexity of construction, an increase in financial and time costs.
• An increase in cost if the trunk is made of steel or aluminum. The use of reinforced polypropylene pipes significantly reduces the construction budget.
• Not everyone likes the abundance of communications in the interior. They can be hidden in walls or boxes. And this is an additional cost and complexity with the service.

What's better?

What to choose: one- or two-pipe design, the master decides individually. Each of them has its own positive and negative properties associated with the features of design, construction, routine maintenance and improvements.

For a small house up to three stories high, a single riser option can be the ideal solution when high-quality results are achieved with minimal investment. But, it should be remembered that in such cases the process of installing additional equipment and replacing old radiators is much more difficult.

How to convert a one-pipe into two?

The two-pipe system is much more efficient in many respects. makes the process of its construction simple and inexpensive. Alteration will not be difficult, but it will require sacrificing the repairs carried out, since you will have to install and gradually increase the return riser and attach batteries to it.

Another option is to install bypasses on the consumers closest to the boiler in order to reduce their temperature and increase the flow of coolants to the final radiators.

If you have experience in this area, please share it. You will provide a valuable service to craftsmen who have not yet made a choice in favor of one or another option for heating their homes.

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

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

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

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

Application example

One of the places where two-pipe heating will be very useful is garage. This is a working room, so there is no need for constant heating. In addition, a do-it-yourself two-pipe heating system is a very real undertaking. Installing such a system in a garage is not necessary, but it will be absolutely not superfluous, since it is very difficult to work here in winter: the engine does not start, the oil freezes, and it’s just uncomfortable to work with your hands. The two-pipe heating system provides quite acceptable conditions for being indoors.

Varieties of two-pipe systems for heating

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

open and closed

Closed systems suggest the use of an expansion tank with a membrane. They can work at high pressure. Instead of ordinary water in closed systems, ethylene glycol-based heat transfer fluids can be used, which do not freeze at low temperatures (up to 40 °C below zero). Motorists know such liquids under the name "antifreeze".

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

open system it is characteristic that the expansion tank must be installed strictly at the highest point of the device. It must be provided with a pipe for air and a drain pipe through which excess water is drained from the system. Also through it you can take warm water for household needs. However, this use of the tank requires automatic feeding of the structure and excludes the possibility of using additives and additives.

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

Horizontal and vertical

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

Two-pipe horizontal heating design found in one-story buildings, and vertical- in high-rise buildings. It is more complex and therefore more expensive. Here, vertical risers are used, to which heating elements are connected on each floor. The advantage of vertical systems is that they usually do not have air pockets, since the air exits through the pipes up to the expansion tank.

Systems with forced and natural circulation

Such types differ in that, firstly, there is an electric pump that causes the coolant to move, and secondly, the circulation occurs on its own, obeying physical laws. The disadvantage of designs with a pump is that they depend on the availability of electricity. For small rooms, there is no particular point in forced systems, except that the house will heat up faster. With large areas, such structures will be justified.

In order to choose the right type of circulation, it is necessary to consider which piping type used: top or bottom.

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

Bottom wiring involves the installation of the pipeline just below the windowsill. In this case, you can install an open expansion tank anywhere in the room slightly above the pipes and radiators. But without a pump in such a design is indispensable. In addition, difficulties arise if the pipe must pass by the doorway. Then it is necessary to let it run along the perimeter of the door or make 2 separate wings in the contour of the structure.

Dead end and passing

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

If, in the Tichelman scheme, radiators with an unequal number of sections are used, the installation of valves or valves is also required here. But even in this case, such a design is balanced easier. This is especially noticeable in extended heating systems.

Selection of pipes by diameter

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

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

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

G=3600×Q/(c×Δt), where:

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

For example, it is known that the heat output for space heating is 3 kW. Then the water consumption will be:
3600×3/(4.187×20)=129 kg/h, i.e. about 0.127 cu. m of water per hour.

In order for water heating to be balanced as accurately as possible, it is necessary to determine the cross section of the pipes. For this we use the formula:

S=GV/(3600×v), where:

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

If the system uses natural circulation, then the speed of movement will be minimal - 0.3 m / s. But in this example, let's take the average value - 0.5 m / s. According to the indicated formula, we calculate the cross-sectional area, and based on it, the inner diameter of the pipe. It will be 0.1 m. We select a polypropylene pipe of the nearest larger diameter. This product has an inner diameter of 15mm.

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

System installation

When installing the structure, certain rules should be followed:

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

How to make the correct connection of heating radiators, which will ensure the most comfortable conditions in the apartment? When installing two-pipe heating systems, it is necessary to adhere to the following sequence:

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

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

Most of the heating systems of multi-apartment and private houses are built according to this scheme. What are its advantages and are there any disadvantages?

Can a do-it-yourself two-pipe heating system be installed?

The difference between a two-pipe heating system and a single-pipe

Let's first decide what kind of animal it is - a two-pipe heating system. That she uses exactly two pipes is easy to guess from the name; but where do they lead and why are they needed?

The fact is that in order to heat the heater with any coolant, its circulation is needed. It can be achieved in one of two ways:

1. One-pipe scheme (the so-called barrack type)
2. Double heating.

In the first case, the entire heating system is one large ring. It can be opened by heating devices, or, which is much more reasonable, they can be placed in parallel with the pipe; the main thing is that a separate supply and return pipeline does not pass through the heated room.

Rather, in this case, these functions are combined by the same pipe.

What do we gain and what do we lose in this case?

• Advantage: minimal material costs.
• Disadvantage: a large variation in the temperature of the coolant between the radiators at the beginning and at the end of the ring.

The second scheme - two-pipe heating - is a little more complicated and costly. Through the entire room (in the case of a multi-storey building - at least on one of its floors or in the basement) there are two pipelines - supply and return.

According to the first, the hot coolant (most often ordinary industrial water) is sent to the heaters in order to give them heat, according to the second, it returns.

Each heater (or a riser with several heaters) is placed in the gap between the supply and return.

There are two main consequences of such a connection scheme:

• Disadvantage: much more pipe consumption for two pipelines instead of one.
• Advantage: the ability to supply a coolant of approximately the same temperature to ALL heating devices.

Tip: for each heater in the case of a large room, it is imperative to install a control throttle.

This will allow you to even out the temperature more precisely, making it so that the flow of water from the supply to the return line on the nearby radiators will not "land" those more distant from the boiler or elevator.

Features of two-pipe heating systems in apartment buildings

In the case of apartment buildings, of course, no one puts chokes on individual risers and regulates the flow of water all the time; equalization of the temperature of the coolant at different distances from the elevator is achieved in a different way: the supply and return pipelines running through the basement (the so-called heating bed) has a much larger diameter than the heating risers.

Alas, in new houses built after the collapse of the Soviet Union and the disappearance of strict state control over construction organizations, it began to be practiced to use pipes of approximately the same diameter on risers and logs, as well as thin-walled pipes installed for welding valves and other nice signs of a new social order.

The consequence of such savings is cold radiators in apartments located at the maximum distance from the elevator unit; by a funny coincidence, these apartments are usually corner and have a common wall with the street. Pretty cold wall.

However, we digress from the topic. The two-pipe heating system in an apartment building has one more feature: for its normal functioning, water must circulate through the risers, rising and falling up and down. If something interferes with it, the riser with all the batteries remains cold.

What to do if the house heating system is running, but the radiators are at room temperature?

1. Make sure the valves on the riser are open.
2. If all the flags and lambs are in the “open” position, close one of the paired risers (we are, of course, talking about the house with where both beds are in the basement) and open the reset located next to it.
   If the water flows with normal pressure, there are no obstacles to the normal circulation of the riser, except for air at its upper points. Tip: Drain plenty of water until, after a long snort of the air-water mixture, a powerful and stable jet of hot water comes out. Perhaps in this case you will not need to go up to the top floor and bleed air there - circulation will be restored after launch.
3. If the water does not flow, try bypassing the riser in the opposite direction: perhaps a piece of scale or slag is stuck somewhere. It can be carried away by countercurrent.
4. If all attempts have not had an effect and the riser does not go to the discharge, most likely it will be necessary to search for a room in which repairs were made and heating appliances were changed. Here you can expect any trick: a removed and muffled radiator without a jumper, a completely cut riser with plugs at both ends, a throttle blocked for general reasons - again in the absence of a jumper ... Human stupidity truly gives an idea of ​​​​infinity.

Top filling system features

Another way in which the installation of a two-pipe heating system is carried out is the so-called top filling. What is the difference? Only that the supply pipeline migrates to the attic or upper floor. A vertical pipe connects the feed filling to the elevator.

Circulation from top to bottom; the path of water from supply to return at the same height of the building is half as long; all the air is not in the jumpers of the risers in the apartments, but in a special expansion tank at the top of the supply pipeline.

The launch of such a heating system is immeasurably easier: after all, for the full operation of all heating risers, you do not need to get into every room on the top floor and bleed air there.

It is more problematic to turn off the risers if repairs are needed: after all, you need to go down to the basement and go up to the attic. Shut-off valves are located here and there.

However, the above two-pipe heating systems are still more typical for apartment buildings. What about private traders?

It’s worth starting with the fact that in private houses the 2-pipe heating system used can be radiant and sequential according to the type of connection of heating devices.

1. Radiation: from the collector to each heater there is its own supply and its own return.
2. Sequential: from a common pair of pipelines, radiators are powered by all heating devices.

The advantages of the first connection scheme boil down mainly to the fact that with such a connection, balancing of the two-pipe heating system is not required - there is no need to adjust the patency of the chokes for radiators located closer to the boiler. The temperature will be the same everywhere anyway (of course, with at least approximately the same length of the rays).

Its main drawback is the largest pipe consumption among all possible schemes. In addition, it will be simply unrealistic to stretch the piping to most of the radiators along the walls, retaining any decent appearance: they will have to be hidden under the screed during construction.

You can, of course, drag it through the basement, but remember: in private houses there are often simply no basements of sufficient height with free access there. In addition, it is somehow convenient to use the beam scheme only when building a one-story house.

What do we have in the second case?

Of course, we have left the main drawback of single-pipe heating. The temperature of the coolant in all heating devices can theoretically be the same. The key word is theoretical.

Setting up the heating system

In order for everything to work exactly the way we want, we need to set up a two-pipe heating system.

The tuning procedure itself is extremely simple: you need to turn the throttles on the radiators, starting from those closest to the boiler, reducing the flow of water through them. The goal is to make sure that a decrease in the flow of water through nearby heaters increases the water consumption at distant ones.

The algorithm is simple: we slightly tighten the valve and measure the temperature on the distant heater. With a thermometer or by touch - in this case it doesn’t matter: the human hand perfectly feels the difference of five degrees, and we don’t need more accuracy.

Alas, it is impossible to give a more accurate recipe, except for “pressing and measuring”: it is an unrealistic task to calculate the exact permeability for each throttle at each coolant temperature, and then also adjust it to achieve the desired numbers.

Two points to consider when adjusting a two-pipe heating system:

1. It takes a long time simply because after each change in the dynamics of the coolant, the temperature distribution stabilizes for a long time.
2. Adjustment of the heating of a two-pipe system should be carried out BEFORE the onset of cold weather. This will prevent you from defrosting your home heating system if you miss the setting.

Tip: with a small amount of coolant, you can use non-freezing coolants - the same antifreeze or oil. It is more expensive, but you can leave the house without heating in winter, without fear for pipes and batteries.

Horizontal wiring system

With the horizontal arrangement of the supply and return pipelines, recently from its patrimony - private and low-rise buildings - it began to penetrate into multi-storey new buildings.

Apparently, this is most due to the fact that studio apartments began to gain popularity: with a large area of ​​\u200b\u200bthe room without internal partitions, it is simply unprofitable to pull risers through the ceilings, as a 2-pipe vertical heating system implies; much easier to do horizontal wiring.

A two-pipe horizontal heating system in a typical modern house looks like this: risers from the basement pass along the porch. On each floor, tie-ins are made into the risers, which supply the coolant to the apartment through the valves and drain the waste water into the return pipeline.

Everything else is exactly like in a private house: two pipes, batteries and chokes on each of them. By the way, a horizontal heating system - two-pipe or one-pipe - is easier to repair: to dismantle and replace a pipe section, it is not necessary to violate the integrity of the ceiling; this, of course, should be written down in the merits of such a scheme.

The horizontal two-pipe heating system has one feature that follows from its design and leaves its mark on the start of heating. In order for the heater to transfer maximum heat from the coolant to the room air, it must be completely filled.

And this means that each such heating device, being in a typical case above the supply and return pipelines, must be equipped with a Mayevsky crane or any other vent in the upper part.

Tip: Mayevsky taps are very compact and aesthetic, but they are not the most convenient device for removing air from a radiator.

Where aesthetics are unimportant (for example, when heating appliances are closed with decorative grilles), it will be more convenient to install a tap with a spout up or a ball valve.

We will not add this feature to the list of shortcomings: bypassing the batteries in one apartment once a year is not a big deal.

As you might guess, a two-pipe horizontal heating system is not only a solution strictly for one-story buildings or for apartment buildings with studio apartments. For example, a two-story house with separate rooms can also be heated in the same way; you just have to make the wiring identical on both floors and bring the pipelines from the boiler to both systems.

Of course, balancing such a heating system will have to take a little more time; but this is a one-time event, and it is not difficult to experience it once in a few years.

Finally - a few definitions and just useful tips.

In the direction of water flow in pipelines, a 2-pipe heating system can be dead-end and direct-flow.

• A two-pipe dead-end heating system is a system in which the coolant moves through the supply and return pipelines in opposite directions.
• In a direct-flow two-pipe heating system, the direction of the current in both pipelines is the same.

In private houses, two-pipe heating systems can be used with both forced and natural circulation.

• Forced circulation of the coolant is provided by a circulation pump; this quiet and low-power device is supplied, in particular, in the same housing with many electric boilers.
• Natural circulation is used in small heating systems; the principle of its operation is based on the fact that hot water has a lower density and rushes up.

A two-pipe closed heating system, that is, a system with constant pressure and without both water intake and the flow of coolant from the outside, is the most popular solution for private houses with electric boilers.

In order to transfer heat to distant rooms from a solid fuel boiler or stove, an open one and two-pipe system is quite suitable.

The project of a two-pipe heating system may include radiators of any type, registers and convectors as heating devices; underfloor heating implies a different connection method.

In order to install the heating of a two-pipe system, it is certainly better to involve specialists in the work. However, the abundance of materials on this topic on the Internet and the ease of assembling modern plumbing and heating systems with the help of fittings and machines for makes it possible for an amateur to do this work - there would be a desire.

If you are installing a two-pipe heating system for a two-story house, when balancing the system, it is worth considering the peculiarity of the communicating floors in terms of heat distribution: all other things being equal, it will always be warmer on the second floor.

Almost all heating systems currently available in any buildings and structures can be attributed to one of the two classes mentioned in the title of this article.

To answer the question of what is better single-pipe or two-pipe heating system, you can only carefully understand the advantages and disadvantages of each of the options considered.

Characteristics of a one-pipe home heating system

Which heating system is more efficient, one-pipe or two-pipe? It is impossible to answer this question unambiguously.

Single-pipe CO has all the basic elements inherent in any heating system. The main ones are:

• A heating boiler operating on any type of fuel that is most available at the location of the heated building. It can be a gas boiler, solid fuel or designed to run on liquid fuel. The type of fuel used by the boiler has no effect on the heating scheme;
• Pipes through which the coolant circulates;
• Shut-off equipment for various purposes (gate valves, valves);
• Heating appliances and thermometers;
• Air bleed valves. Placed on radiators (Maevsky cranes) and at the top point of CO;
• Drain cock (at the bottom point of CO);
• Expansion tank of open or closed type.

Benefits of using single pipe systems

The difference between a single-pipe heating system and a two-pipe one is that the first one is by far the simplest and most effective way to heat buildings up to 150 m2.

The installation of a circulation pump and the use of modern technical solutions make it possible to guarantee the required temperature parameters in heated rooms. Therefore, answering the question, what to choose a one-pipe or two-pipe heating system, among the indisputable advantages of the first system, it should be noted:

Mounting versatility. Such a system can be installed in a building of any configuration, and a closed circuit guarantees the movement of the coolant along the entire perimeter of the heated premises.
Unlike two-pipe, one-pipe CO can be mounted in such a way that space heating starts from the coldest side of the building (northern), regardless of the boiler installation location, or from the most significant rooms (nursery, bedroom, etc.).

The installation of the system requires a minimum number of pipes and shut-off and control equipment, a complete installation of CO is carried out in much less time than CO with two pipes. All this allows you to get serious savings in the funds allocated for the payment of construction work.

The system allows the installation of pipes directly on the floor or under it, which allows you to implement any design solutions in the premises.

The scheme provides for serial and parallel connection of heating devices, which allows you to control the temperature in them and adjust it;

Subject to certain requirements during installation, the system can be made in a non-volatile version. In the event that the pump stops due to a power failure, the coolant supply line switches to a parallel line. In this case, CO, from the variant with forced (PC) circulation, switches to natural circulation (EC).

Disadvantages inherent in the specified variant of CO

Two-pipe or one-pipe heating system of a private house? When evaluating the pros and cons, it should be borne in mind that the main disadvantage of a single-pipe CO is the fact that the heaters are connected in series. And this, during operation, excludes the possibility of effective temperature control in one of them, without affecting the other radiators.

A factor influencing the choice of whether a two-pipe or one-pipe heating system of a private house will be installed at your facility, one should not forget about such a disadvantage of the latter as increased pressure in the system compared to the two-pipe version. This can be achieved by increasing the power of the circulation pump installed in the system, which entails an increase in operating costs and increases the likelihood of leakage, and also requires more frequent addition of coolant to the system.

The system requires vertical filling. And this automatically determines the location of the expansion tank in the attic and, accordingly, the solution of the issue with its insulation.

If such a system is mounted in a two-story building, then another problem arises. The temperature of the water entering the first floor may differ from that which is initially supplied to the second floor by almost 50%. To avoid this, it is required to install additional jumpers on each floor, and the number of sections of heating devices on the first floor should significantly exceed that which is mounted on the second.

Which heating system is more efficient, one-pipe or two-pipe? We have already considered the first one. Let's consider the second.

Such a system a priori implies the presence of 2 pipelines placed along the perimeter of the heated room. Radiators cut between them, which dampen pressure drops and create hydraulic jumpers. However, the problems created by this can be leveled out due to the correct configuration of the CO.

• Two-pipe systems can be vertical and horizontal, depending on the location of the supply and return (parallel to the ceilings or perpendicular to them). However, it should be understood that the circuit mounted in apartment buildings is essentially a horizontal two-pipe CO.

  A two-pipe vertical one will turn out when the radiators are installed not in the gaps of the risers (as in the case described above), but between the supply and return.

• Associated and dead-end SO. The first variety includes systems in which hot water, passing through the radiator, moves in the same direction along the return line. If the direction of movement of the coolant changes after the heater, the system is classified as a dead end.

  The required option is selected taking into account the presence of doorways on the CO pipe laying line, which are quite difficult to get around, it is easier to return the water in the direction in which it came.

• With bottom and top filling.
• With natural (EC) and forced (PC) circulation.

Advantages and disadvantages of the system

Schemes of one-pipe and two-pipe heating systems are compared according to their inherent advantages and disadvantages. The advantages of the second system can be called:

1. Receipt in all heating devices of a coolant with the same temperature, which allows you to set your own value of the required temperature for a specific room;
2. Less pressure loss in the lines, which allows the use of a lower power pump (savings in operation costs);
3. The system allows installation in buildings of any area and number of storeys;
4. The presence of shut-off valves allows you to perform preventive maintenance and repair without stopping the entire CO.