Owners of private houses often face a choice of what type home heating give preference. There are only two types of heating systems traditionally used in everyday life: one-pipe and two-pipe. Each type has both advantages and disadvantages. The difference between both systems is in different ways delivery of coolant to heating devices. What heating structure for own home It’s better to choose one-pipe or two-pipe directly to the owner of the house, taking into account his own household needs, the expected heated area and the availability of finances.
In the first option, heat is distributed throughout the house through one pipe, sequentially heating each room of the house. In the second case, the complex is equipped with two pipes. One is a direct supply of coolant to the . The other pipe serves to drain the cooled liquid back into the boiler for subsequent heating. Correct assessment of your own financial capabilities, accurate calculation optimal parameters coolant in each individual case will help not only determine the type heating system, but also competently.
You can understand and figure out what is best for you, a single-pipe or two-pipe heating system, only after carefully studying the technical nuances.
Single pipe heating system. General views
A single-pipe heating system can work with both a pump and natural coolant circulation. When considering the second type, you should delve a little into the existing laws of physics. It is based on the principle of expansion of a liquid when heated. During operation, the heating boiler heats the coolant, which, due to the temperature difference and the pressure created, rises along the riser to the highest point of the system. The coolant moves upward through one pipe, reaching the expansion tank. Accumulating there hot water already through the downpipe it fills all the batteries connected in series.
Accordingly, the first connection points along the coolant flow will receive maximum heat, while the radiators located further away will already receive partially cooled liquid.
For large, multi-story buildings, such a scheme is extremely ineffective, although in terms of installation costs and maintenance, a single-pipe system looks attractive. For private one-story houses, residential buildings with two floors, a similar principle of heat distribution is acceptable. Heating of residential premises using a single-pipe circuit in one-story house quite effective. With a small heated area, the temperature in the radiators is almost the same. The use of a pump in longer systems also has a positive effect on the uniformity of heat distribution.
The quality of heating and the cost of installation in this case may depend on the type of connection. Diagonal connection of radiators provides greater heat transfer, but is used less frequently due to the larger number of pipes required to connect all heating devices in residential premises.
The scheme with bottom connection of radiators looks more economical due to lower consumption of materials. From an aesthetic point of view, this type of connection looks preferable.
Advantages of a single-pipe heating system and its disadvantages
For owners of small residential buildings, a single-pipe heating system looks tempting, especially if you pay attention to its following advantages:
- has stable hydrodynamics;
- convenience and ease of design and installation;
- low costs for equipment and materials.
To indirect advantages single pipe system can be attributed to the safety of the supply of coolant, which disperses through the pipeline through natural circulation.
To the most common problems that owners of a single-pipe heating system have to face include the following aspects:
- technical difficulties in eliminating miscalculations in the work made during the design;
- close relationship of all elements;
- high hydrodynamic resistance of the system;
- technological limitations associated with the impossibility self-adjustment coolant flow.
Despite the listed disadvantages of this type of heating, a well-designed heating system will allow you to avoid many difficulties even at the installation stage. In view of the listed advantages and economic component, single-pipe schemes have become quite widespread. Real benefits They have both a single-pipe and another type, a two-pipe heating system. What can you win and what can you lose by choosing one of the types for your home?
Technology for connecting and positioning a single-pipe heating system
Single-pipe systems are divided into vertical and horizontal. In most cases, vertical wiring is used for multi-story buildings. In this case, all radiators are connected in series from top to bottom. With horizontal wiring, the batteries are connected one after another horizontally. The main disadvantage of both options is frequent air jams due to air accumulation in the radiators. The proposed diagram makes it possible to get an idea of some wiring options.
Connection methods in this case are chosen at the discretion of the owner. Heating radiators can be connected via side connection, diagonal or bottom connection. The figure shows similar connection options.
Always for the owner of the house important aspect remains economic expediency equipment installed in the house and the resulting effect. Do not underestimate the option of a single-pipe heating system. Today in practice there are quite a few effective measures to improve heating circuits of this type.
Eg: There is a technical solution that allows you to independently regulate the heating of individual radiators connected to the same line. For this purpose, bypasses are created in the system - a section of pipe that creates a bypass movement of the coolant from the direct pipe to the return, bypassing the circuit of a certain battery.
Valves and flaps are installed on the bypasses to block the flow of coolant. You can install thermostats on radiators that allow you to regulate the heating temperature in each radiator or throughout the system as a whole. A competent specialist will be able to calculate and install bypasses to achieve maximum efficiency. In the diagram you can see the principle of operation of bypasses.
Two-pipe heating system. Operating principle
Having become familiar with the first type of heating system, single-pipe, it’s time to understand the features and operating principle of a two-pipe heating system. Thorough analysis of technological and technical parameters heating of this type allows consumers to make independent choice- which heating is more effective in a particular case, single-pipe or two-pipe.
The basic principle is the presence of two circuits through which the coolant disperses throughout the system. One pipe supplies coolant to the heating radiators. The second branch is designed to ensure that the already cooled coolant, after passing through the radiator, returns to the boiler. And so constantly, in a circle, while the heating is on. At first glance, the very presence of two pipelines in the scheme may repel consumers. The large length of highways and the complexity of wiring are factors that often scare away owners of private houses from a two-pipe heating system.
This is at first glance. Like single-pipe systems, two-pipe systems are divided into closed and open. The difference in this case lies in the design of the expansion tank.
Closed with a membrane expansion tank are the most practical, convenient and safe to use. This is confirmed by obvious advantages:
- even at the design stage it is possible to equip heating devices thermostats;
- parallel, independent connection of radiators;
- the technical possibility of adding heating devices after installation is completed;
- ease of use of a hidden gasket;
- the ability to turn off individual radiators or branches;
- ease of system adjustment.
Based on the above, one clear conclusion can be drawn. A two-pipe heating system is much more flexible and technologically advanced than a single-pipe one.
For comparison, the following diagram is presented:
The Two-Pipe System is very convenient for use in a house in which it is planned to increase the living space; extension options are possible, both upward and along the perimeter of the building. Already at the work stage, technical errors made during the design can be easily eliminated. This scheme is more stable and reliable than a single-pipe one.
With all the obvious advantages, before choosing this type of heating, it is appropriate to recall the disadvantages of the two-pipe system.
It is important to know! The system is characterized by higher complexity and installation costs and rather cumbersome connection options.
If you have a competent specialist at hand, the necessary technical calculations, then the listed disadvantages are easily compensated by the advantages of a two-pipe heating circuit.
As in the case of a single-pipe system, the two-pipe option involves the use of a vertical or horizontal pipeline arrangement. Vertical system– radiators are connected to a vertical riser. This type is suitable for two-story private houses and cottages. Air jams are not a problem for you. In the case of the horizontal option, the radiators in each room or room are connected to a pipeline located horizontally. Two-pipe horizontal heating circuits are mainly designed for heating single-story buildings and large residential buildings with the need for floor-by-floor adjustment. Air jams that arise can be easily eliminated by installing Mayevsky valves on radiators.
The figure shows a vertical two-pipe heating system. Below you can see what a horizontal two-pipe system looks like.
Traditionally, radiators can be connected using bottom and top wiring. Depending on the technical specifications and the project - the choice of wiring option depends on the owner of the house. Top wiring is more convenient. All lines can be hidden in the attic space. The system creates the circulation necessary for good distribution of coolant. The main disadvantage of a two-pipe heating scheme with an upper wiring option is the need to install membrane tank outside heated rooms. The upper distribution does not allow the intake of technical water for household needs, as well as connect the expansion tank with a tank for hot water used in everyday life. This scheme is not suitable for residential properties with a flat roof.
Summary
The selected type of heating for a private home should provide all residents of the residential building with the necessary comfort. There is no point in saving on heating. By installing a heating system in your home that does not meet the parameters of the residential property and household needs, you risk spending a lot of money on refurbishment in the future.
Two-pipe or single-pipe heating system - the choice should always be justified, both from a technical and economic point of view.
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 to make the most optimal choice, both technically and in terms of the necessary means, to understand whether a single-pipe or two-pipe heating system 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;
- no special infrastructure requirements.
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 main reason Why the single-pipe system has become widespread in our country is an 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 single-pipe system must withstand increased 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 to a vertical riser heating devices(for example, eleven), 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 a heating system with one main riser is installed in a one-story building, then it will be possible to get rid of at least one significant shortcoming such a scheme – uneven heating.
If such heating is implemented in multi-storey building, then the upper floors will be heated much more intensively 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 routed 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 have parallel connection in contrast to sequential - with single-pipe.
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 a design (see), on the basis of which both heating devices and the main pipes themselves will be selected (see). The final decision is yours.
Almost all heating systems currently available in any buildings and structures can be classified into one of the two classes mentioned in the title of this article.
The question of whether a single-pipe or two-pipe heating system is better can only be answered by carefully understanding the advantages and disadvantages of each of the options considered.
Characteristics of a single-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 that runs on any type of fuel that is most available at the location of the heated building. This can be a gas, solid fuel or liquid fuel boiler. The type of fuel used by the boiler does not have any effect on the heating circuit;
- Pipes through which the coolant circulates;
- Shut-off equipment for various purposes (valves, gate valves);
- Heating appliances and thermometers;
- Valves for bleeding air. Placed on radiators (Maevsky taps) and at the top point of the CO;
- Drain tap (at the lowest point of CO);
- Expansion tank of open or closed type.
Advantages of using single pipe systems
The difference between a one-pipe heating system and a two-pipe one is that the first is by far the simplest and in an effective way heating buildings up to 150 m2.
Installation of a circulation pump and 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 single-pipe or two-pipe heating system, including undeniable advantages The first system should be noted:
Versatility of installation. Such a system can be installed in a building of any configuration, and a closed loop guarantees the movement of the coolant along the entire perimeter of the heated premises.
Unlike two-pipe, single-pipe CO can be installed in such a way that heating of the premises begins from the coldest side of the building (north), regardless of where the boiler is installed, or from the most important rooms (children's room, bedroom, etc.).
Installation of the system requires a minimum number of pipes and shut-off and control equipment, complete installation CO is completed in much less time than CO with two pipes. All this allows you to get serious savings in funds allocated for 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 makes it possible to control and regulate the temperature in them;
If certain installation requirements are met, 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 is switched to a parallel branch. In this case, CO, from the version with forced circulation (PC), switches to natural circulation (EC).
Disadvantages inherent in the specified CO option
Two-pipe or one-pipe heating system for a private house? When assessing the pros and cons, it should be taken into account that the main disadvantage of single-pipe CO is the fact that the heating devices are connected in series. And this, during operation, eliminates the possibility of effectively adjusting the temperature in one of them, without it affecting the remaining radiators.
The factor influencing the choice of whether a two-pipe or one-pipe heating system for a private house will be installed at your facility; do not forget about the disadvantage of the latter, such as increased pressure in the system compared to the two-pipe option. 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 leaks, 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 attic space and, accordingly, solving the issue of its insulation.
If similar system mounted in two-story building, then another problem arises. The temperature of the water entering the first floor may differ by almost 50% from that initially supplied to the second floor. To avoid this, it is necessary to install additional jumpers on each floor, and the number of sections of heating devices on the first floor should significantly exceed that installed on the second.
Which heating system is more efficient, one-pipe or two-pipe? We have already considered the first one. Let's look at the second one.
Such a system a priori implies the presence of two pipelines located around the perimeter of the heated room. Radiators are inserted between them, which dampen pressure drops and create hydraulic bridges. 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 mounted in apartment buildings the circuit is essentially a horizontal two-pipe CO.
A two-pipe vertical one will be obtained in the case 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 SOs. The first type includes systems in which hot water, passing through the radiator, moves in the same direction along the return line. If after the heating device the direction of movement of the coolant changes, the system is classified as a dead end.
The required option is selected taking into account the presence of CO pipes on the line doorways, which are quite difficult to bypass, 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 are:
- The supply of coolant to all heating devices at the same temperature, which allows you to set your own required temperature for a specific room;
- Lower pressure losses in the lines, which allows the use of a lower power pump (saving operating costs);
- The system allows installation in buildings of any size and number of floors;
- Availability shut-off valves allows you to perform preventive maintenance and repairs without stopping the entire CO.
Organizing the heating of a private home is not an easy job, requiring maximum attention to each stage. First of all, you need to decide which heating system to use: one-pipe or two-pipe? Your task is to choose the most effective option strapping, so that in the future you will not reap the fruits of your mistakes in the form of eternally cold ones. And in order to understand which of the systems is better, we will understand the technical nuances and operating principles of each, and also compare their pros and cons.
Distinctive features of a one-pipe system
Single-pipe piping operates to the utmost simple principle: water circulates through closed system from heating device To heating radiators. In this case, the equipment is united by one circuit. All technical units connected in series by a common riser. In a private house, a hydraulic pump can be used to supply coolant - it creates the pressure in the system necessary to effectively push water through the riser. Depending on the installation option, the single-pipe system is divided into two types:
- Vertical - involves connecting radiators to one vertical riser according to the “top to bottom” scheme. Based on the installation features, the system is only suitable for two or three-story private houses. But at the same time, the heating temperature on the floors may differ slightly.
- Horizontal - provides for serial connection of batteries using a horizontal riser. Best option for a one-story house.
Important! There should be no more than 10 radiators per riser of a single-pipe system, otherwise extremely uncomfortable temperature contrasts in different zones heating
Pros and cons of a single-pipe system
When it comes to the advantages and disadvantages of single-pipe piping, everything is not so clear, therefore, in order to rationally evaluate the system, we will understand in detail the specifics of its pros and cons.
Among the obvious advantages:
- Cost-effective - assembling a one-pipe system does not require a large number of working materials. Saving on pipes and various auxiliary elements makes it possible to reduce financial expenses for connecting the heating system.
- Easy to install - you only need to install one coolant line.
Single-pipe horizontal system heating
Disadvantages of single-pipe piping:
- Inability to control individual batteries - in the basic version, single-pipe piping does not allow you to separately regulate the flow of coolant to a specific radiator and adjust the temperature in different rooms.
- The interdependence of all elements - in order to repair or replace any device, it is necessary to completely turn off the heating system.
At the same time, if desired, the indicated shortcomings can be easily leveled with the help of closing devices - bypasses. They are jumpers with taps and valves that block the flow of coolant to a separate battery: if you need to repair any device, simply block the water supply to it and start repairing without fear of leakage necessary work– water will continue to circulate in normal mode common system heating, bypassing the blocked area. In addition, thermostats can be connected to the bypasses to control the operating power of each specific battery and separately regulate the room heating temperature.
Technical details of a two-pipe system
The two-pipe system operates according to a complicated scheme: first, the hot coolant is supplied through the first branch of the pipeline to the radiators, and then, when it has cooled down, the water flows back to the heater through the return branch. Thus, we have two fully functional pipes.
Like single-pipe piping, two-pipe piping can be made in two variations. So, depending on the specifics of connecting heating equipment, the following types of heating systems are distinguished:
- Vertical - all devices are connected by a vertical riser. The advantage of the system is the absence of air locks. Minus - comparatively high price connections.
- Horizontal - all components of the heating system are connected to a horizontal riser. Due to its high functionality, the harness is suitable for one-story dwellings with a large heating area.
Advice. When installing a horizontal two-pipe system, it is necessary to install a special Mayevsky valve in each radiator - it will perform the function of bleeding air plugs.
In turn, the horizontal system is divided into two more subtypes:
- With bottom wiring: hot and return branches are located in the basement or under the floor of the lower floor. Heating radiators should be located above the heater level - this improves coolant circulation. An overhead air line must be connected to the common circuit - it removes excess air from the network.
- With overhead wiring: hot and return branches are laid in the upper part of the house, for example, in a well-insulated attic. The expansion tank is also located here.
Pros and cons of a two-pipe system
Two-pipe piping boasts a considerable list of advantages:
- Independence of system components - pipes are routed in parallel collector circuit, which ensures their isolation from each other.
- Uniform heating - the coolant is supplied to all radiators, no matter where they are located, at the same temperature.
Two-pipe heating system
- There is no need to use a strong hydraulic pump - the coolant circulates through the two-pipe system by gravity thanks only to gravitational force, so there is no need to use powerful power for heating pump equipment. And if there is a weak pressure of the water flow, you can connect the simplest pump.
- Possibility of “expanding” batteries - if necessary, after assembling the equipment, you can extend the existing horizontal or vertical piping, which is unrealistic with a single-pipe version of the heating system.
The two-pipe system also has disadvantages:
- Complicated connection diagram for heating equipment.
- Labor intensive installation.
- The high cost of organizing heating due to large quantity pipes and auxiliary devices.
Now you know the difference between single-pipe and two-pipe heating systems, which means it will be easier for you to decide in favor of one of them. Before you do final choice, carefully evaluate the technical and functional pros and cons of each of the pipings - this way you will understand exactly what system is needed to heat your particular private home.
Connecting heating radiators: video
Heating system: photo
Let's compare what you need to choose - a single-pipe heating system, the so-called Leningradka, or a two-pipe one. Which one is cheaper to create and which one is better in terms of performance.
What are the opinions, what do the experts say?
The single-pipe heating system has been used quite widely, it is efficient and many of its owners will say that in their opinion it works either well or satisfactorily. At the same time, upon first consideration, two-pipe systems look clearly more expensive, because two conductors are used instead of one. This, according to some, increases prices not only in terms of materials, but also during installation and clutters up the space.
But experts are more likely to point out that a two-pipe heating system for a private home is cheaper and works better, and you need to choose it. Why is that?
Serious disadvantages of a single-pipe heating system - temperature difference
In a one-pipe heating system, where all radiators are connected in series, the latter will be colder than the previous ones. But how much will the temperature decrease? And how will this affect comfort?
The temperature drop will depend on the amount of liquid passing through the ring main pipeline. How larger diameter pipes and the higher the speed in it, the less will be the influence of each radiator. By increasing these parameters, we can achieve, for example, that on five batteries the temperature drop will be no more than 10%. But this is in theory.
In practice, we are limited by the reasonableness of the costs for pipe diameters and their tees, as well as the choice of pump - choose the right low-power one circulation pump, and set it to first speed so that it consumes no more than 30 W of electricity.
In this case, in “Leningrad without madness,” we use a main pipe with a diameter of 26 mm for metal-plastic, or 32 mm (outer) for polypropylene, to connect four radiators in a ring. The radiator connections are 16 mm (20 mm polypropylene).
Then the power drop on each radiator will be about 7%. At the same time, the temperature will drop by about 4 degrees, and these are not the worst indicators.
Therefore, if the 1st radiator is 60 degrees, then at the entrance to the 4th we will already get +48 degrees C. In principle, the functionality of this circuit is maintained up to 4 heaters per ring. But 5 pcs. It can no longer be recommended - there is a significant loss of power and an increase in the costs of compensating for it by increasing the radiator itself.
And 8 pieces - etc. - completely ineffective temperature schemes that cannot provide comfort, since the temperature drop on a ring with an acceptable diameter and pump power (without creating water noise) will be completely critical - up to 32 - 36 degrees.
How to prevent the temperature from decreasing in Leningrad
- There is an opinion that you can install thermal heads on radiators, raise the temperature in the boiler and thus hope that the last radiator in a row of 8 pieces will someday heat up. In fact, this is completely wrong, if only for the reason that you have to wait - when it is already hot in the first room, then in the last there is still a glacier.
It is also not correct to operate the boiler in high temperature mode, when it must often turn off - it has heated the rooms, turned off, then warmed up again...
- Another option to equalize the temperature in single-pipe radiators is to install additional balancing valves on the first radiators in order to turn them off and send more liquid to the last ones. The result is an expensive and difficult to customize system.
- Now the option recommended by experts is to increase the power of the radiators from what is required by calculation. The increase should be proportional to the cooling of the water. For 8 the battery is almost 100%. Expensive and cumbersome, but the heating power of rooms and the air temperature in them can be equalized.
Which is cheaper and more profitable - single-pipe or double-pipe?
A single-pipe not only entails setup difficulties, but it is also more expensive - only due to the increased diameter of the pipeline and its fittings.
Let's calculate how much the materials for typical scheme heating small house approximately 110 sq. m., - the first floor is 60 sq. m., approximately 6x10 m, and the attic is 50 sq. m., 5x10 m. There are 4 units installed on each floor. radiators. A reasonable minimum pipe diameter for is 26 mm.
For a two-pipe scheme, 20 mm is suitable for both shoulders and risers, with such a small number of radiators. And we connect the second battery at the dead end already 16 mm.
Placing radiators around the perimeter of the house, 4 pcs. per floor, we get the following:
For a single-pipe we will need the following pipe lengths and diameters:
- 26 mm – 70 m.
- 16 mm – 5 m.
- Tees 26 mm – 18 pcs.
For a two-pipe we need
- 20 mm – 42 m
- 16 mm – 50 m
- Tees 20 mm – 14 pcs.
Then the difference in price only for a branded metal-plastic pipeline is about $200 - installation of a single-pipe will be more expensive. And if we add even a small increase in the power of the latest radiators (as recommended), then it’s already $250.
True, if you use cheap polypropylene the difference in price will be small, but still Leningrad will be much more expensive than modern system heating with supply and return.
Unacceptable but cheap scheme
What if you turn on the radiators according to the circuit without a ring pipe, but simply by connecting them in series? After all, then the price is minimum. But the cooling of the coolant will be very significant, and include more than 3 pieces. batteries are not worth it according to this scheme.
The maximum number of radiators is 4 pieces, but at the same time the power of the latter drops by 35 - 40%.
Those. This scheme is also viable; it can be useful with 3 radiators in a ring. And with 4, there is a significant cost to increase its size and power, so it won’t be any cheaper.
Conventional dead-end two-pipe circuit, what are the advantages
The usual two-pipe dead-end circuit allows you to place 4 radiators in an arm, without balancing valves, and the temperature drop will be a maximum of 5% on the last radiator, which cannot even be detected without instruments. If you place 5 batteries, then without balancing with taps, the power output on the latter will drop to 15%, which is also acceptable.
The diameters of the pipes are as follows.
- A 26 mm line extends from the boiler, then in the shoulders to the penultimate radiator - 20 mm, and to the last radiator - 16 mm.
- Radiators are connected 16 mm.
- For polypropylene, the outer diameters are 32, 25, 20 mm, respectively.
As indicated, the cost of creating such a system is minimal; balancing is not required even between arms, if the dead ends are approximately equal in power and pipe length.
Where and when is single-pipe heating used?
Mono-tubes were previously widely used in centralized systems, where they laid steel pipes large diameter, and the pump was no joke. The systems are still in use and new ones are being designed, mainly based on industrial enterprises, where there are kilometers of pipes, and then the system becomes more profitable.
Also, the risers of high-rise buildings are the same heating systems with one pipe, where a central pump provides high pressure. But as soon as the temperature or pressure drops, which is not uncommon (due to lack of energy, in some places the valves are screwed on specially), the radiators on the 5th floor of the Khrushchev building become not at all comfortable, although on the 2nd it is still somehow acceptable, oh what the residents of such houses themselves can tell. This is a pronounced disadvantage of a single-pipe heating system.
As we see, it is possible to use Leningrad, it has the right to life, but only in very small systems, if for some reason only one pipeline needs to be laid, although in general it will cost more. The main choice should be a heating system with all radiators connected using two pipes.