Heating wiring diagram for two wings. Horizontal heating system

Effective work autonomous water heating systems is one of the essential conditions comfortable living in private households. The availability of installation, ease of operation, economy and efficiency make such complexes quite popular among owners of private houses. Almost today, up to 70% of private households in cities and towns of our country are heated in this way. Of the existing options, in the first place is the two-pipe heating system of a private house - the most practical and affordable for autonomous heating of housing.

What is a two-pipe heating system

In everyday life, you can find various private houses, however, it is up to the inhabitants of the residential building to choose which option for supplying heat is better. Many factors influence the choice of the structure of the heating system. Preference for one or another scheme is given based on the availability of funds from the owners of the house, the expected effect and design features of the residential building. The two-pipe system is used more often in practice due to its high efficiency, reliability and ease of adjustment.

Two-pipe systems autonomous heating still commonly called. In other words, the circulation of the coolant from the boiler to the radiators is carried out along two circuits. The first pipe directly supplies heat from the boiler to the radiators, while the second pipe is designed to transport the cooled coolant back. Despite certain technical difficulties associated with the installation of the pipeline, the wiring diagram of this type of heating circuit is simple and understandable. For comparison, you can look at the diagram of a single-pipe and two-pipe heating structure in order to understand the fundamental differences and the principle of operation.

A single-pipe system is one circuit with a coolant. , in contrast to a single-pipe, where the pipe with the coolant is one single circuit, more flexible and convenient in terms of technology. The batteries in this case are connected in parallel, which plays an important role in the operation process. Depending on household needs, each radiator can be removed from a single system at any time by closing the corresponding valve.
Read also about forced circulation!

Advantages and disadvantages of a two-pipe system

Among the advantages of a two-pipe heating scheme, the following stand out:

• the same coolant temperature in all batteries, regardless of their location in relation to the boiler;
• the ability to turn off the heat supply to a single radiator;
• the ability to install a thermostat on each battery;
• technical capabilities to connect a large number of radiators.

Parallel connection allows individual installation temperature for each heater, allowing residents to independently regulate the level of heating in each room separately.

Having certain advantages over other heating systems used in private homes, the two-pipe heating scheme has one drawback - the increased length of the pipes. Often this aspect affects the increase in the cost of the system. It is appropriate to recall the aesthetic side of the issue. Two pipes laid in residential areas are more difficult to hide.

Two-pipe heating system, varieties

There are two types of two-pipe heating scheme:

• with forced circulation;
• with natural circulation of the coolant.

The efficiency of the heating system depends on the type of circulation. Which scheme should be installed in the house, or horizontal wiring, with an upper or lower connection of radiators, all these issues are resolved based on the heated area, configuration and number of storeys of the house.

The method with natural circulation is focused on changing the density of the coolant during the heating process. The heated coolant with a lower density rises, and then fills the radiators by gravity, gives off heat and returns to the boiler due to the slope of the return pipeline.

Due to the difference in the height of the boiler, expansion tank and heaters in the pipeline creates a certain working pressure. The higher open storage tank, the greater the pressure and the more intense the forward flow of the coolant in the pipeline.

Important! We can say that an open heating system with natural circulation is completely autonomous. There is no pressure pump, and therefore no need for electricity.

Mostly today, a two-pipe closed circuit heating, in which the pump is turned on. It provides more intensive circulation of the coolant and greater heating efficiency. Heating with forced circulation has great technological capabilities. The only drawback is that a power outage completely stops the system.

Unlike the scheme with forced circulation, the length of the system with gravity flow of the coolant has significant limitations, no more than 30 meters. That is, such a heating system is suitable only for small rooms (dachas, saunas, country houses).

Important! When installing a natural circulation system, pipes with a diameter of at least 1¾ inches must be used. The slope of the pipe for the direct supply of the coolant and the return pipe should not be less than 3-4 0.

In order to get an idea about existing options connection, what is the difference between the scheme of a two-pipe heating system with lower wiring, from the option with top connection what is the difference between horizontal and vertical type, enough to get started to familiarize yourself with the video.

Types of wiring of the heating system

Pipes can be mounted vertically or horizontally. Vertical heating systems have a number of advantages, among which it is worth highlighting the uniformity of pipes and the large difference in pressure of the coolant at the inlet and outlet, respectively.

A vertical two-pipe heating system with an upper wiring option is more convenient and easier to install. The laying of the pipeline does not depend on the layout of the building. Most of the pipes of the heating system can be hidden in the attic space, hidden by suspended ceilings. A similar arrangement of heating pipes is often used in multi-storey buildings where it is necessary to ensure good forward flow in the pipeline, with a large number of radiators. In this case, the intensity of circulation of the coolant in the pipeline depends on the height of the riser.

According to the location of the pipelines, two-pipe heating systems are vertical and horizontal, with top, bottom or combined wiring. The option with the top connection is more expensive. In each heated room, two pipes will have to be led out throughout the wall panels, direct heat supply and return. There is little aesthetics in this, the length of the pipeline increases significantly.

A two-pipe heating system with a lower wiring looks preferable, despite large quantity pipe bends, connection points and stretched communications.

Radiators at horizontal installation with bottom connection option can be easily hidden behind decorative screens. In this case, your home can be appropriately decorated using a variety of design elements. Piping with bottom wiring is easy to hide in Wall panels, or floor screed.

What does the optimal heating system for a private house look like?

Foresee everything technical details and technological parameters of autonomous heating is necessary at the project stage. Giving preference to one or another scheme, it is important that the future heating meets the relevant parameters and household needs.

There is no good or bad wiring. In each individual case, the heating efficiency depends on the correct connection and a well-designed project. In practice, often the owners of residential buildings are faced with a situation where, as a result of the development of the project and the subsequent installation of the pipeline, a dead-end heating system arises. In them, the coolant entering the radiator is forced to collide with a cooled, oncoming flow of spent coolant. This type of connection is used for two-pipe systems with a horizontal pipeline. It is impossible to say that such heating is not profitable and inefficient. The most popular is a two-pipe horizontal heating scheme with a lower wiring with a passing movement of the coolant.

There are two types of coolant flow patterns: associated and dead-end. In the proposed table, you can see the comparative parameters of both options for the movement of the coolant

Be sure to read: which is more effective,?

Important! The two-pipe horizontal heating scheme is convenient, practical in operation. Moreover, during the installation process appears real opportunity divide the heating circuit into two wings, providing heat for almost the entire living space Houses.

Installation of a two-pipe heating system horizontal type it is mainly used for heating one-story residential buildings, when the task is to connect a large number of radiators. Connecting batteries involves two options:

• ray;
• consistent.

The option with a beam connection of heating devices is also called radial. For serial connection, a conventional pair of pipelines is used. Both the first and second connection types have their advantages. In a radial connection, there is no need to install chokes that control the operation of radiators located close to the boiler. The temperature in all radiators is the same. This type is very convenient for private, one-story houses.

Good heating system serial connection. Significantly saves consumables.

The good work of heating in a private house depends on many factors, starting with a competent choice of the type and type of heating, ending with a properly drawn up project. Hydraulic calculations, which are integral integral part project - the work of a qualified specialist. Adjustment of the two-pipe heating system is carried out before the start of the heating season, when there is time to eliminate technical problems and inconsistencies.

Heating in a private house on two wings
A large area always pleases residents until they encounter heating. Noticing that there is not enough heating for two wings and it is getting cold, it is necessary to look for a solution. The first way to create heating in a private house with two wings is a two-pipe heating system. Perhaps the only way to heat an apartment and a house on two sides.
For designing a house, it is possible to use exclusive option- install the heating system yourself. AT recent times manual installation has become very relevant, so consider the correct installation of heating.
Features of installation in a private house

Effective method heating is achieved with a two-pipe heating system. The uniqueness lies in the regulation of the heat pressure. The change in temperature is controlled manually.
The direct and return circuit of the heat mixer has a special feature in a two-pipe system. The supply pipe treats water from a common boiler. Radiators, serpentines, underfloor heating systems receive the disassembled flow. Discharge occurs through pipes reverse side.

As in any heating system, there are positive principles of operation:
In a two-way heating system, the flow is easily regulated.
Suitable for installation on any floor.
Additional broach properties allow installation not only on two wings, but also on a large area.
The cost of installation work is estimated by the budget expense.
In order to install heating of a two-pipe system, fuss with paperwork is not required.

Heating in a private house with two wings is installed according to the rules. Natural and forced circulation is also carried out in a one-pipe system. The same type of system is affected by the upper and lower current supply.
If we compare in terms of aesthetics, then two-pipe heating takes first place. Since the wires do not stick out and installation is easy. It should be understood that the distribution of sections depends on the connection:
Lateral.
Diagonal.
Lower.

It is not so difficult to carry out heating, for two wings. On the second and first floors, radiators with electric heating. In addition, apply modern technologies. Floor heating simplifies general heating. Thus, heating in a private house with two wings is simple task for a welder or electrician. It is better to deal with heating issues with masters of a certain qualification, as well as experienced workers. Return to list RANDOM INFO:

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A very significant advantage of a gravity-flow water heating system is its independence from the availability of electricity. Gravity heating can also be created at a remote dacha based on a non-volatile solid fuel boiler. The system is silent and reliable, it will undoubtedly be in demand in the future.

A lot of experience has been gained in creating gravity-flow heating systems, because previously everything water heating created on the principle of self-flow. The system can be created according to the "typical folk scheme" and with your own hands.

The disadvantages are restrictions on power, heated area, the possibility of connecting additional circuits, at an increased price for creation.

Gravity heating is more expensive, about 2 times more expensive than forced circulation systems, as it requires a large pipe diameter and special boiler placement. The difficulty in creating is that large-diameter pipes must have a common slope, which means that their position is fixed and therefore they often do not fit into the design of the room, clutter up the interior.

How the gravity system is calculated

You can order a thermal and hydraulic calculation from specialists, in licensed organizations, but it will not be cheap. You can make these calculations approximately using well-known programs or manually.

In any case, the speed of fluid movement through the system is not large. The larger the internal diameters of the pipeline and radiators, as well as the boiler, the more liquid will pass through them, the more energy can be transferred.

It is important to answer the question - will there be enough energy to transfer the coolant to heat a particular building? This is the essence of the calculations. But if there are no calculations, then you need to turn to the experience of creating such heating and insulation of buildings.

Loss of energy and ensuring the movement of fluid

First, you need to determine the degree of insulation of the building - whether it meets the requirements normative documents. If not, then not only the gravity system may not have enough power ..... It is more expensive to heat a cold building, it is necessary to insulate, and not increase the heating capacity.

After the building is insulated, one can turn to the experience of creating such systems, from which it is known that the usual limiting area for gravity heating is 150 square meters. on each floor of the building, while it is desirable to distribute radiators into 2 arms on each floor, and the length of the supply pipeline of each arm should not exceed 20 meters.

A prerequisite for creating a system is the excess of a hot coolant (usually the middle line of radiators is taken) over a cold one (the middle line of the boiler heat exchanger).

With a longer length of pipelines, a calculation would be desirable, or it is necessary to put up, which is possible, during the peaks of frost bandwidth system (coolant velocity) may not be enough to make the building hot.

Consider what will determine the performance of a gravity-flow system.

Features of the heating system with natural circulation

The pressure in a gravity system will directly depend on the height of the water column with the difference in water densities (temperature difference) and on the very difference in water densities. The force formula is shown below.

The greater the difference between the supply and return temperatures, and the higher the water column with this difference, the faster the water will circulate, the more heat will be carried over more reliable system and large area can be heated.

The fact is that water cools most significantly in radiators, before them it is considered hot. After the radiators, cold water moves along the return line to the boiler heat exchanger, where it is heated. Therefore, the lower the heat exchanger is relative to the radiators, the greater the pressure in the system.

In addition, the water cools down in the pipe itself leaving the boiler, which means that the higher the hot pipeline is raised, and the longer it is and gives off more heat, the greater the pressure.

However, this heat transfer will be of low efficiency for heating the house if the hot piping is located under the ceiling. It is better if it is located along the floor of the heated massandra and is a heating device for it.

It is not right to simply make a high column of hot water, bringing the expansion tank above the roof. The greatest height difference is needed, at which a temperature difference would occur, and this is easier to achieve by lowering the boiler.

A typical mistake when creating a gravity system for 2 floors is to connect radiators on both floors to the same risers. As a result, it will still be cold on the 1st floor, when it is already very hot on the 2nd floor. It is correct for the attic to provide a separate independent heating arm with its own control valve.

System feature:
- liquid in a gravity system usually cools down significantly, due to the low speed of its movement. The difference between the supply and return temperatures is often in the range of 25 - 30 degrees. The temperature regime, for example, is 75 degrees. exit from the boiler and 45 deg. return line. Therefore, it is unacceptable to create a scheme with a single pipeline with series connection of radiators. Only passing and dead-end two-pipe wiring diagrams are suitable.

How does the coolant (water) move

From the above, it follows design features gravity heating system.

The boiler is located in a pit, in the basement, in any case, it is desirable that its heat exchanger be lower than the middle line of the radiators.

All pipelines are made with a general slope in the direction of fluid movement:

• water from the boiler rises along the vertical riser to the highest point;
• from the vertical hot riser should always go down to the entrance to the boiler;
• the difference in height between the start and end point of the pipe is at least one percent, but the slope can change as you like along the length;
• it is always better to provide maximum slope.

Which pipes to use

The diameter of the pipes for supply and return on one wing of the pipeline must be at least 32 mm, while radiators can also be connected with pipes with an internal diameter of 20 mm. And for the riser and supply to the wing - at least 50 mm. However, no one forbids increasing these diameters, which will only make the system more powerful.

So far, ordinary steel pipes are considered the optimal option. With large diameters, they become competitive with plastic. Besides steel pipe large diameter is in itself a heating device, due to the significant conductivity of heat by the metal.

Boiler, radiators, pipeline

A special boiler is used (both gas and solid fuel) with its own small hydraulic resistance, designed for a gravity-flow system.

Radiators with low hydraulic resistance are used, with a large diameter of internal holes - usually either cast iron or aluminum.

At the highest point of the pipeline, an air bleed valve is installed (pressure system with a closed expansion tank (hydraulic accumulator)). A safety group is built into the system at the outlet of the boiler - a pressure gauge and an emergency valve. Or at the highest point there is an open-type expansion tank.

The drain valve is located in the area of ​​​​the boiler at the lowest point of the pipeline; a tap is made either to the sewer or to the tank.

The selection of the boiler in terms of power is carried out as usual - depending on the heat loss of the building, and radiators - on the heat loss of each room where they are installed.

At the same time, the rule is more often used - radiators are slightly more powerful in total than the boiler (this takes into account the fact that the passport temperature of the liquid is usually higher than the real one, i.e. radiators are purchased even more powerful by 20 - 35%), after which general power radiators are distributed among the rooms.

Gravity heating schemes for one wing

A typical scheme of water heating with gravity fluid movement. There is only one wing here. The hot pipeline is located higher, from it the risers go down to each radiator or to a pair of radiators. The diagram shows an expansion tank instead of a hydraulic accumulator.

In practice, such schemes are often implemented so that the expansion tank, the upper pipeline would be located in the attic, and the return line often goes under the floor to the basement. At the same time, pipelines clutter up the living space less and do not spoil the interior. But then all pipelines in the cold zone must be well insulated - a layer of at least 15 cm mineral wool. Styrofoam is not suitable, as it is eaten by rodents and should not be heated to 70 degrees.

Laying pipes in the attic

A sub-variant of this scheme - the return line is raised up, since it is not always possible to lay it down - doorways interfere, there is no basement, etc.

In a small house

The option of placing radiators right next to the boiler. This is only possible in climatic zones with a constant positive temperature, and if the windows are sufficiently insulated ( double glazing), and there is no special need to create thermal curtains by placing radiators under the windows. The scheme is used when it is not possible to lower the level of the boiler - pipelines are reduced as much as possible.

Pipeline on two wings

The next example is more in demand in life. More often, pipelines are located in this way during the gravity flow of fluid in a small private house or in a country house at the level of radiators with a general slope.

The pipeline is divided into two wings, which it is desirable to make the same length. All radiators are connected through valves for quick control of water flow.

For two floors

Another example "from life" of piping with gravity flow of fluid. This time it's heating up full floor and attic.

Since the attic wing is low-power, it is connected by a pipeline of a smaller diameter - 25 mm. Here, risers are used for each pair of radiators in the rooms on the first floor, and a hot pipeline is laid along the floor of the attic and is a heating element for it.

The scheme requires the creation of sufficient pressure, so the boiler heat exchanger is located at least half a meter below the middle line of the radiators on the first floor.

Principles and Conclusions

You can develop any number of gravity heating schemes, depending on the specific layout of the house, but always respected following principles- the largest column of water with a temperature difference, the maximum diameters of pipelines and special boilers and radiators, the ring of pipelines - "supply-radiator-return" are made as short as possible, for which the pipeline is divided into several arms, which are connected to the boiler in parallel.

Also important: - if gravity heating in the house was created independently, or the owners took an active part in its creation, then all the identified shortcomings during operation can be corrected by their own hands or the system can be without special costs improved, when its shortcomings were identified.

Basically, water heating is used for heat supply of the housing stock. When arranging it, a one- or two-pipe system is mounted. In the second case, two pipes are required for the heating to function. The heated coolant flows through one of them to the radiators, and through the other, the cooled water from the battery returns to the boiler.

Pros and cons of the two-pipe option

With a heating system in two pipes, any heating boilers on different types of fuel. In this case, the circulation of the coolant is gravity or forced. Two-pipe systems are mounted in buildings of different heights.

Their main disadvantage is related to the way of organizing the movement of the heat carrier. Compared to a single-pipe heating structure, a larger amount of pipe products will be required. The cost of purchasing building materials will be higher, but not by much, since pipes and fittings with a smaller diameter are used to lay a two-pipe system. But it will take more time to complete the installation.

But the above negative points compensated by the fact that when laying a two-pipe heating system, a thermostatic head can be installed on each radiator, which makes it easy to balance the operation of the structure in automatic mode, which is not available when using a single-pipe version.

On the this device you need to set the required temperature of the coolant, and it will be maintained all the time with a slight error (its exact value depends on the model of the device).

During operation single pipe system it is possible to regulate the operating mode of each of the radiators individually. This will require a bypass with a three-way or needle valve, and this measure will complicate the design and increase its cost, which will negate the savings in both money for the purchase of components and time for work.

Another disadvantage of the two-pipe system is the inability to repair radiators without stopping their operation. To get rid of this inconvenience, near each battery on the supply and return lines they put Ball Valves. Their presence allows you to shut off the coolant supply, remove the device and repair it. All other elements of the heat supply structure will be able to function as before for as long as you like.

Space heating through a two-pipe system has a significant advantage over a single-pipe system: hot water of the same temperature is simultaneously supplied to each of the radiators from the boiler. Despite the fact that the coolant tends to move along the path of minimum resistance and not go beyond the first battery, the use of thermal heads or taps that regulate the intensity of the water flow can solve the problem.

Other benefits include:

• minimum pressure loss in the system;
• easier to organize gravity heat supply;
• application pumping units lower power if forced circulation of the coolant is used.

Classification of two-pipe heating systems

Heating structures are:

• open;
• closed.

AT closed system use a membrane-type expansion tank, so that it has the ability to work at elevated pressure. For its functioning, not only water can be used as a coolant, but also liquids with ethylene glycol, which have a lower freezing point, they are also called antifreezes.

To provide normal work equipment in heating structures, it is necessary to use compositions designed specifically for this purpose, and not general purpose and even more so you can not use automobile. The same requirement applies to additives - they should only be specialized.

It is especially important to comply this rule when operating modern heating units with automatic control. The fact is that the repair of such expensive equipment in the event of a malfunction will not be guaranteed even in cases where the breakdown is not related to the quality of the coolant.

AT top point open system, an open-type expansion tank is placed. A pipe is connected to it to remove air plugs from the system. Sometimes this tank is used as a source warm water for household needs, but then the system should be fed automatically and additives and additives should not be used.

As far as security is concerned, it is preferable to use closed structures and therefore modern heating boilers most often developed specifically for them.

Vertical and horizontal system diagrams

Two-pipe heat supply structures are of two types:

1. vertical. It is usually used in multi-storey buildings. Two-pipe vertical heating system needs to be used a large number pipe products, but the connection of radiators on each of the floors can be easily done. Its main advantage lies in the automatic removal of air - it rushes to the top and there it comes out through the drain valve or expansion tank.
2. Horizontal. Such a system has found application in single-story, maximum two-story buildings. To bleed air from it, so-called Mayevsky cranes are mounted on batteries.

Heat carrier distribution options

Systems, depending on the organization of the supply of heat carriers, come with an upper or lower wiring. When a two-pipe heating system with top wiring, then the pipeline is laid under the ceiling, and the supply pipes from it are lowered down to the radiators. The return line is mounted along the floor covering.

The advantage of this option is that you can easily make a system in which the coolant moves thanks to natural circulation. The fact is that due to the difference in heights, a flow arises that can provide the required speed of movement, for which it is necessary to provide a sufficient slope angle.

But the scheme of the heating system with the top wiring has become less popular due to its unaesthetic appearance. True, from above it can be hidden under a stretch or suspended ceiling, and then only the pipes leading to the batteries, which can be removed into the walls, will be visible.

Both the lower and upper wiring options are used in vertical two-pipe structures. In the case of lower wiring, the supply pipeline is laid below, but higher than the return pipe.

You can also place the supply line in the basement or semi-basement, between the finished floor and its rough base. In this case, the return line is laid below. The coolant is supplied or drained to the batteries through holes made in the floor.

With the arrangement of pipes arranged in this way, the connection will turn out to be hidden and at the same time aesthetic. But in this case, the location of the boiler should be selected. If the system operates with forced circulation, the location of the heating unit relative to the radiators does not matter, since the flow will push the pump. As for structures with natural movement of the coolant, the batteries must be located above the level of the boiler, for which it must be deepened.

In a two-story private household, a two-pipe heating system should have a lower type of wiring and two wings, in each of them the temperature will be regulated by valves. The coolant in it moves with the help of forced circulation and for this reason the boiler is placed on the wall.

Dead-end and associated systems in two pipes

A dead-end is a heating structure in which the coolant in the supply and return pipelines moves into opposite directions. The system with passing movement is called the loop or the Tichelman scheme - it is easier to balance and adjust, especially with a long network.

If it has radiators having the same number of sections, then it will be balanced automatically, unlike the dead-end option, when each battery requires the installation of a needle valve or thermostatic valve.

Even when the radiators have a different number of sections in the Tichelman two-pipe heating system and you still need to use valves / valves, it will be easier to balance it than a dead-end one, especially with sufficient length.

To balance a two-pipe structure with a multidirectional flow of coolant, the valve should be screwed on the first heater as tightly as possible. It is even possible that a situation will arise when it will need to be closed so that the coolant will stop flowing there. Then there is a choice: either the first radiator will not heat in the network, or the last one, otherwise the heat transfer cannot be adjusted.

Heating systems for two wings

As practice shows, homeowners most often equip a heat supply system with a dead-end scheme, since it is more difficult to lay it with a long return line. With a small circuit, it is possible to balance the heat transfer on each battery in the case of a dead-end connection.

When the length of the circuit is large, and there is no desire to use the Tichelman scheme, it can be divided into two smaller wings. For such a device, the network must have technical possibility. In both circuits, after separation, valves are installed to adjust the flow rate of the working medium in each of them. Without these details, balancing the system is quite difficult.

Connecting radiators in a two-pipe system

When arranging a two-pipe heating structure, radiators can be connected in a one-sided, lower, diagonal (cross) way. The last option is considered the best. At cross connection heat transfer from the heater reaches 95-98% of the rated battery power.

For each connection option, heat loss is different, but they are all used, however, in different situations. The lower option occurs when pipelines are laid under the floor. Radiators with hidden laying can be connected according to other schemes, but then considerable sections of pipes will be visible.

Lateral connection is practiced when the number of sections does not exceed 15, if their number is greater, then a diagonal option is used - otherwise the heat transfer and circulation rate will suffer.

In view of the foregoing, it should be noted that before connecting a two-pipe heating system, you need to decide on its installation scheme, since the amount of materials needed and, of course, the cost of work depend on it.

The two-pipe heating system was named based on the principle used in its organization. Such a system is equipped with two pipes: through one pipe, the heated coolant is sent to the batteries, through the other, the cooled water from the heating elements is fed back to the boiler.

Two-pipe systems are compatible with boiler equipment operating on all types of fuel, can be equipped with both natural and forced circulation of the coolant. Installation of two-pipe systems is possible both in low-rise and in high-rise buildings.

Advantages and disadvantages

Let's start with the disadvantages:

1. The main disadvantage of the two-pipe principle is increased consumption materials. However, this disadvantage is offset by the fact that this scheme uses pipes of smaller diameter. The same can be said about fitting sizes. Smaller sizes – less cost materials, and hence the price.
2. Another disadvantage of such a heating scheme is the increased labor costs. This is natural, since there are twice as many pipes.
3. Inability to repair batteries without shutting down the entire system. You can correct the situation if the calculation of a two-pipe heating system provides for the presence of ball valves near all heating devices (both on the supply and on the return). After shutting off the taps, you can repair the battery or heated towel rail.

Scheme of a two-pipe system

The advantages of two-pipe heating include the following facts:

1. A thermostatic head can be installed on each battery, so that the balance in the system will be maintained automatically. With a single-pipe device, it is difficult to implement control on individual radiators, since a bypass with a three-way or needle valve is required, which will make the system much more expensive and more complicated.
2. In contrast to a one-pipe device, in a two-pipe system, water of the same temperature is supplied to all heating elements - directly from the boiler. The intensity of the water supply is regulated by thermostatic heads and taps, so pressure problems are excluded.
3. Small pressure losses and much more simple implementation heating based on gravity. If pumps for forced circulation are needed, equipment of less power can be used than in the case of single-pipe systems.

Equipment classification

The two-pipe heating system of a private house can be open or closed. The latter provides for the presence of a membrane expansion tank, which allows the system to operate at high pressure.

The heat carrier can be not only water, but also ethylene glycol compounds capable of operating at low temperatures(up to 40 degrees below zero). Ethylene glycol-based compounds are called antifreezes.

It should be noted that right job equipment is provided only when using specialized compounds designed specifically for heating purposes. Automotive antifreeze will not work. The same applies to additives and additives: only those specially adapted for heating can be used.

It is especially important to follow this recommendation when operating expensive boiler models that are controlled by automation. In the event of a boiler breakdown, manufacturers usually disclaim responsibility and do not comply with warranty repair if the fault is not directly caused by the thermal medium.

Closed systems are different highest level security, therefore most of boilers modern production targeted at such schemes.

Scheme of an open heating system with an expansion tank

AT open systems expansion tank mounted on the top. A pipe is attached to the tank for air outlet, as well as a pipe for draining excess water from the system. Can be taken from the tank hot water for domestic needs, but in this case it is desirable to make the water supply automatic. In addition, water used for the needs of residents should not contain technical additives and additives.

Two-pipe system of vertical and horizontal types

There are two types of organization of a system with two highways - vertical and horizontal. Vertical pipe arrangement is commonly used in multi-apartment buildings. To implement the system, many pipes are needed, but at the same time, the possibility of outlets to apartments on each floor is achieved. The main advantage of such a system is the natural return of air, as it rushes up, where it is discharged using an expansion tank or a drain valve.

A two-pipe horizontal heating system is more common in one-story and two-storey houses. Mayevsky cranes are used here to remove air.

Top and bottom wiring

The distribution of the coolant supply is carried out according to one of two principles: upper or lower. If the wiring is top, the pipeline is located in the subceiling space, and the supply pipes go down to the batteries. The return goes along the floor. The advantage of this option is that it makes it easy to organize natural circulation, since due to the height difference and a specially angled pipe, a good speed of the coolant is ensured.

However, systems with bottom wiring are not very popular due to the external unattractiveness of conspicuous pipes. The problem can be corrected by covering the pipeline with a suspended or stretch ceiling.

Note! Both types of wiring are used in two-pipe systems. The differences in the schemes are clearly shown in the figure below.

Scheme of a vertical two-pipe system

If the wiring is arranged according to the lower principle, the supply pipe is located at the bottom, but slightly above the return. Moreover, pipes can be installed even in the basement, semi-basement or built into the floor. This method of wiring is more aesthetic, and therefore is popular.

However, with the lower method, it is necessary to carefully choose a place for installing the boiler (if we are talking about the natural circulation of the coolant), since the batteries must be located above the boiler. In the case of forced circulation, the position of the equipment relative to the batteries does not matter.

Scheme of water lines in the heating system

Two-pipe heating system two-story house divided into two wings. In both wings, the temperature level is regulated by means of valves. The lower type of wiring and forced circulation are used, so the boiler is attached to the wall.

Dead-end and associated systems

A system in which the coolant moves in different directions through the supply and return pipes is called a dead end. Another option is a system with a passing direction of the coolant (Tichelman scheme). A passing scheme is easier to balance and adjust, especially when it comes to large-scale heating networks.

In an associated system with an equal number of radiator sections, there is no need to balance. In a dead-end scheme, one cannot do without installing thermal valves or needle valves on all radiators.

Dead-end and associated flow diagram of the coolant

Moreover, it should be noted: even if there are batteries with a different number of sections in the associated circuit, it will be much easier to establish a balance than in an extensive dead-end type system.

To balance the dead-end circuit, you need to tightly tighten the valve on the first battery. It may well develop a situation in which water completely stops flowing into the radiator. Then you will need to choose: which of the batteries will be excluded from the heating circuit - the first or last.

Heating system with two wings

And yet, the installation of a two-pipe heating system is often carried out according to the dead-end principle. The reason is that in associated schemes, the return line has a large length and installation work more difficult. In addition, with a small heating circuit, the heat transfer from each battery can be completely balanced.

In the case of a large contour, it can be divided into a pair of wings. However, it should be remembered that in order to create a system with two wings, one must proceed from the technical admissibility of its construction. In both circuits, valves must be installed to control the power supply of the heat carrier. Without valves, balancing will not work.

In two-pipe heating, one of three options for connecting batteries is used: diagonal, one-sided or bottom. The best way is considered diagonal connection. This way you can achieve maximum heat transfer from heating equipment(up to 98% of the nominal value).

For all the differences between different types connecting radiators, they are all used in practice, but with different tasks. For example, connecting according to the lower principle does not have high performance, but it a good option if the piping is to be placed under the floor.

Disguised laying of pipes can also be used in a diagonal and one-sided scheme, however, in these cases, significant sections of pipes will remain on the surface, which can only be hidden under wall decoration.

Connection of side-type radiators is used when the number of sections is limited to 15 units - heat loss in this case are practically non-existent. If there are more than 15 sections, a diagonal connection will be required, since only this method will ensure normal circulation of the coolant and heat transfer.