Pros and cons of one-pipe and two-pipe heating systems - which is better and more efficient? One-pipe and two-pipe heating system - making the right choice One-pipe or two-pipe system for the house.
All existing heating systems can be divided into two groups:
- single-pipe;
- two-pipe.
To answer the question: which heating system is better single-pipe or two-pipe, it is necessary to understand by what principle each of them works.
This will clearly indicate the advantages and disadvantages of each of them, and will also help you make the most optimal choice, both technically and in terms of the necessary funds, in order to understand a one-pipe or two-pipe heating system is more suitable.
Videos on types of heating systems can be easily found on the World Wide Web.
Advantages of a one-pipe heating system
- fewer materials and means;
- hydrodynamic stability;
- lower complexity of design and installation;
- no special infrastructure requirements.
But with all these advantages, we can say with full confidence that a single-pipe system is far from the best scheme by which heating can be implemented. Still, the main reason why the single-pipe system has become widespread in our country is the undeniable savings in material.
Single-pipe heating system: principle of operation
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-storey building).
All heating devices (heat transfer units - batteries or radiators) are connected in series to the downstream line.
Modernization of single-pipe heating systems
A technical solution that makes it possible to regulate the operation of each individual heater has been developed.
It consists in connecting special closing sections (bypasses), which make it possible to integrate automatic radiator thermostats into heating. What other benefits are possible with the installation of bypasses? We will talk about this in detail later.
The main advantage of such a 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.
Due to this, such a heater is repaired or replaced without shutting down the entire system.
Bypass is a bypass pipe equipped with valves or taps. With the correct connection of such fittings to the system, it will allow you to redirect the flow of water through the riser, bypassing the repaired or replaced heater.
It is not difficult to understand that the task of installing such devices into the system with your own hands is hardly possible to solve, even if detailed instructions are available. In this case, one cannot do without the participation of a specialist.
A heating system with one main riser should be equipped with heating devices that have improved characteristics in terms of reliability. Any devices in a one-pipe system must withstand increased pressure and high temperature.
Vertical and horizontal riser layout
According to the implementation scheme itself, single-column heating can be of two types:
- vertical;
- horizontal.
If the heating devices are connected from the upper floor to the lower one, this is a vertical riser. If the batteries are connected in series to each other in all rooms of the floor of the building, this is a horizontal riser.
Disadvantages of a single-pipe heating system
- complexity of thermal and hydraulic calculation of the network;
- the difficulty of eliminating errors in the calculations of heating devices;
- the interdependence of the characteristics of the operation of all devices in 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 more than ten heating devices are connected to a vertical riser (for example, eleven), then the water temperature on the first radiator in the network will be about 105 ° C, and on the last - 45 ° C.
Single-column heating in individual construction
If heating with one main riser is installed in a one-story building, then it will be possible to get rid of at least one significant drawback of such a scheme - uneven heating.
If such heating is implemented in a multi-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 stories high. Therefore, the installation of 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 collector system
- It becomes possible to install automatic thermostats for batteries or heating radiators. In this case, such devices are provided at the design stage of the system;
- Pipes according to this scheme are bred through the premises through a special collector system. If one of the elements in the system fails or starts to work unstably, this does not affect the operation of other devices in the circuit;
- In other words, with a two-pipe system, the elements of the heat circuit are connected in parallel, in contrast to the serial connection - with a single-pipe system.
The main disadvantages of a two-pipe heating system
- heating becomes more complex according to the connection scheme;
- the price of the project requires more funds;
- circuit wiring is more labor intensive.
Where are two-pipe heating systems used:
- in individual housing construction;
- in the projects of the so-called "elite" housing;
- 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 a horizontal floor distribution, or a two-pipe system with an upper vertical wiring.
This will provide better circulation.
Advantages of two-pipe collector heating
- reduced hydrodynamic resistance;
- the possibility of independent temperature control in each room.
Before starting, the collector heating system requires careful preliminary adjustment. For the correct installation, installation and operation of a two-pipe system, it is necessary to have the appropriate infrastructure.
Variants of wiring diagrams for a two-pipe system
Top wiring
The overhead system is suitable for natural circulation (without pumps) (). It has a lower hydrodynamic resistance. In this case, the upper supply main pipe is partially cooled. Due to this, an additional circulation pressure of the coolant is formed.
Bottom wiring
In a system with bottom wiring, both the supply and discharge pipes are located side by side.
There are such modifications of the lower wiring:
So, one-pipe heating system or two-pipe? In each case, it is necessary to have preliminary calculations and a project (see), on the basis of which both heating devices and the main pipes themselves will be selected (see). The final decision is yours.
When designing a heating system, the question arises: “What kind of heating system will we make? One-pipe or two-pipe? In this article we will understand what these systems are and how they differ. To make things clear, let's start with definitions.
Definitions of one-pipe and two-pipe systems.
- Single-pipe - (abbreviated as OSO) is a system in which all heating devices (radiators, convectors, and so on, we will abbreviate them as software) are connected to the boiler in series using one pipe.
- Two-pipe - (abbreviated as DSO) is a system in which two pipes are supplied to each PO. According to one of them, the coolant is supplied from the boiler to the software (it is called the supply), and through the other, the cooled coolant is diverted back to the boiler (it is called the "return").
For the sake of completeness, we add two more definitions. According to these definitions, there is a division according to the principle of laying the supply line:
- With upper wiring - the hot coolant is first supplied from the boiler to the highest point of the system, and from there the coolant is supplied to the software.
- With lower wiring - the hot coolant is first discharged horizontally from the boiler, and then rises up the risers to the software.
Single pipe heating system.
As described above, in OCO all heating devices are connected in series. Passing through them, the coolant will cool down, so the “closer” the radiator is to the boiler, the hotter it will be. This fact must be taken into account when calculating the number of sections of heating radiators. The “farther” the radiator is from the boiler, the lower the temperature of the coolant will be in it and the more sections will be needed for heating. Lower wiring is possible only for houses with one floor and forced circulation in the system. With two or more floors, an upper piping is already needed.There are two types of OSS:
- OSO, in which heating devices are installed on the "bypass" (bypass jumper).
- Flow OCO - all devices are connected in series without jumpers.
The second type is unpopular due to the difficulty of regulating the temperature in radiators, which is caused by the fact that it is impossible to use special fittings (thermostatic valves). Since when closing or reducing the flow through one radiator, the flow through the entire riser decreases. The main advantage of OCO is the lower cost of components and easier installation. The most popular version of a single-pipe system is Leningradka.
What is "Leningrad".
According to legend, this system got its name from the city where it was first applied. But of course, it is impossible to confirm this reliably, and I don’t really want to. So, "Leningradka" is a one-pipe heating system in which the software is installed on the "bypass". This allows you to regulate the temperature of individual radiators or convectors or turn them off altogether, if necessary. All the advantages and disadvantages of a single-pipe system are inherent in Leningrad, therefore, for distant radiators, it is necessary to increase the number of sections. Various piping options are available:
- Horizontal - the pipe lies in a horizontal plane and radiators are already installed on it.
- Vertical - the pipe runs vertically through the floors and radiators are connected to it.
OSO of the "Leningradka" type is best used for small private houses, where the number of floors does not exceed two. For large cottages with extended heating systems, such a "Leningrad" is not suitable.
An example of the implementation of "Leningradka" Two-pipe heating system.
The main advantage of DSO is that the coolant comes to all software equally hot. This allows not to increase the number of sections on the "distant" radiators. That is, the most efficient use of heating devices occurs. The presence of two separate pipes for supply and return makes the installation of such a system more expensive. For such systems, both top and bottom piping and horizontal or vertical piping are possible.
In addition, DSO may differ in the direction of the coolant flow:
- Dead-end systems - water in the supply and return pipes flows in different directions.
- Flow systems - water in the supply and return pipes flows in the same direction.
Drawing from the book "Heating and water supply of a country house" Smirnova L.N. You can use a two-pipe system for houses of any size, but it is most suitable for large cottages. Its use will allow you to change the flow rate of individual radiators, without affecting all the others. That is, it will be possible to use various room thermostats, which will create comfortable conditions for all residents.
Summary of the article.
The question of choosing the type of heating system depends on several factors:
- your budget
- area of your house.
- Features of the internal structure of the house. For example, the number of floors
- The number of heating devices.
Most often, for small country houses (no more than 2 floors), a single-pipe system is better suited, and for large cottages (with a floor of 2 or more floors and a large length of pipelines), a two-pipe heating system will be more effective. Specific features of the implementation of a particular system are best discussed with a professional designer.
The heating system is divided into two types: one-pipe and two-pipe. Obviously, it is most advantageous to install a more efficient one that will not only cope with its functions, but will also serve you for more than one year. In order not to remain "out of the blue" and not make a mistake with the choice of the heating system.
You need to properly understand which of the heating systems is best for you and why.
Thus, you will know which system is better from a technical point of view and how to choose it, taking into account your budget.
High water pressure ensures a natural cycle, and antifreeze makes the system more economical.
Disadvantages of a single pipe system - a very complex thermal and hydraulic calculation of the network, since, having made a mistake in the calculations of devices, it is very difficult to eliminate it.
Also, this is a very high hydrodynamic resistance and an involuntary number of heating devices on one line.
The flow of the coolant goes immediately to everything and is not subject to separate adjustment.
In addition, very high heat losses.
In order to be able to regulate the operation of individual devices connected to one riser, bypasses (closing sections) are connected to the network - this is a jumper in the form of a piece of pipe connected by a direct and return radiator pipes, with taps and valves.
To be able to control the temperature of each individually, the bypass allows you to connect automatic thermostats to the radiator.
In addition, it also makes it possible, in the event of a breakdown, to replace or repair individual devices without turning off the entire heating system.
Single-pipe heating is divided into vertical and horizontal:
- vertical - this is the connection of all batteries in series from top to bottom.
- horizontal - this is a serial connection of all heating devices on all floors.
Due to the accumulation of air in batteries and pipes, so-called traffic jams occur, which is a disadvantage of both systems.
Installation of a one-pipe system
Connection is made according to the scheme, using valves for airing radiators, which block the valves and plugs.
Crimping system - after which the coolant is poured into the battery and the system adjustment is directly adjusted.
Two-pipe heating system
The advantage of a two-pipe heating system - this is the installation of automatic thermostats, which gives you the full ability to adjust the temperature in individual rooms.
This also includes the independence of the operation of the circuit devices, which is provided by a special collector system.
The difference between a two-pipe and a single-pipe system is that in the first one you can connect additional batteries after connecting the main ones, as well as the possibility of extending in vertical and horizontal directions.
Unlike a single-pipe, here you can also easily correct permissible errors.
The disadvantages of this system are minimal if you have enough material resources and have the opportunity to call the master.
Installation of a heating system with lower horizontal piping
This system allows you to locate the open tank in a convenient warm place. Also, it is possible to combine expansion and supply tanks allow you to use hot water directly from the heating system itself.
In systems with forced circulation, to reduce pipe consumption, the discharge and supply risers are located at the level of the first.
Currently, two types of piping are used for heating systems: single-pipe and two-pipe. The presence of various housing stock allows you to choose the most efficient type of heating for each individual situation.
The comfort in the home during the cold season and the reasonable savings in money for the purchase of material and installation largely depend on the correct choice of the heating system. Having studied the pros and cons of the systems, it will be possible to make the best choice for your home, apartment.
Single pipe heating
The principle of operation of such a system is quite simple, along the riser (supply line) the hot coolant rises to the last floor of an apartment building and goes down the main line, passing through the heating devices of each floor. The intensity of heating will decrease from top to bottom, although in a private 1-2-storey household there is no big difference in temperature difference, the heating of radiators occurs evenly.
The advantages of such a system:
- Hydraulic stability of the system;
- Ease of design and installation of the system, which significantly affects the timing of the work;
- The cost of the material is reduced by a line consisting of one pipe with a coolant;
- A single-pipe line does not overload the design of the premises with complex engineering solutions for wiring and connecting radiators;
- The use of modern radiators, shut-off valves for balancing the system and automatic temperature controllers ensures uniform heating of the air in the premises;
- Shut-off valves provide the ability to dismantle any radiator in the system without stopping the heating system and discharging water in the system.
Negative aspects of using a single-pipe system
- Requires the production of an accurate hydraulic and thermal calculation of the system;
- Difficulty in performing system reconstruction or eliminating calculation and installation errors due to system imbalance;
- High degree of dependence in the operation of heating devices from each other;
- The system is limited to 8-10 radiators on one riser, the temperature difference from the first radiator to the last one depends on their number and can cause significant underheating of the premises in winter;
- High hydraulic resistance overloads the circulation pump and requires more performance from it;
- To compensate for heat loss, an increase in the number of radiator sections at the end of the riser is required.
During the operation of such a system, many measures have been developed to improve its operation, which allow you to control the operation of heaters connected to one riser without a significant change in the temperature regime of adjacent radiators in the common system.
Each radiator is equipped with a bypass transit pipeline, this is a jumper with a tap, valve or automatic thermostat that manually or automatically regulates the supply of boiler water to the heating radiator. The presence of shutoff valves allows you to completely exclude the radiator from the system without compromising the heating of the entire house. The correct calculation, installation and balancing of such a system can only be performed by a certified heating engineer.
Distribution of the heating system with two pipes
Such a system serves the battery system with two pipes: a hot coolant supply and a return to return the cooled water back to the boiler.
Currently, this system is recognized by most experts as the most reliable in operation and safe for used heating devices.
Advantages of a two-pipe system:
- Ease of implementation of temperature control in each room without changing the operation parameters of neighboring radiators in the system (on the riser);
- Ease of installation of radiators, which ensures the independent operation of each element of the system;
- Changes in the heating system in the future will in no way lead to a violation of the temperature balance in the premises, in other words, you can add a radiator anywhere or change the number of its sections;
- The possibility of freezing of the heating system in the end sections in insufficiently insulated or office premises has been minimized.
The disadvantages of such a system:
- More complex installation of the system due to the connection diagram of heating devices;
- Additional material consumption due to the increase in the number of pipes;
- Complex decoration of pipes and assemblies in a small apartment and limited areas.
Each type of heating system has its pros and cons, but if you want to get more comfort with a total area of heated premises over 100 square meters. m, you need to opt for a two-pipe system. In European countries, the single-pipe system was abandoned in the last century. Well, problems arise in any systems with a certain curvature of the hands ...
Evgeny Sedov
When hands grow from the right place, life is more fun :)
Content
Today, there are a variety of ways to organize systems, among which heating on two wings with a pump has gained great popularity. Its device is made according to the principle of effective maintenance with minimal heat loss. The two-pipe heating system has become especially in demand in single-storey, multi-storey and private houses, the connection of which allows you to achieve all the necessary conditions for a comfortable stay.
What is a two-pipe heating system
Two-pipe heating has been used more and more often in recent years, and this despite the fact that the installation of a single-pipe version is usually much cheaper. This model provides the ability to adjust the temperature in each room of a residential building at will, because. a special control valve is provided for this. As for the one-pipe scheme, unlike the two-pipe one, its coolant, when circulating, sequentially passes absolutely all radiators.
As for the model of two pipes, here a pipe is separately supplied to each radiator, designed to inject the coolant. And the return pipeline is collected from each battery into a separate circuit, the function of which is to deliver the cooled carrier back to the flow or wall-mounted boiler. This circuit (natural / forced circulation) is called the return flow, and it has become especially popular in apartment buildings when it becomes necessary to heat all floors with a single boiler.
Advantages
Double-circuit heating, despite the higher installation cost compared to some other analogues, is suitable for objects of any configuration and number of storeys - this is a very important advantage. In addition, the coolant that enters all heating devices has an identical temperature, which makes it possible to evenly heat all rooms.
The remaining advantages of a two-pipe heating system are the possibility of installing special thermostats on radiators and the fact that a breakdown of one of the devices will in no way affect the operation of others. In addition, by installing valves on each battery, you can reduce water consumption, which is a big plus for the family budget.
disadvantages
The above system has one significant disadvantage, which is that all its components and their installation are much more expensive than the organization of a single-pipe model. It turns out that not all tenants can afford it. Other disadvantages of a two-pipe heating system are the complexity of installation and the large number of pipes and special connecting elements.
Scheme of a two-pipe heating system
As mentioned above, a similar method of organizing a heating system differs from other options in a more complex architecture. The dual-circuit heating scheme is a pair of closed-type circuits. One of them is used to supply the heated coolant to the batteries, the other is to send the spent, i.e., cooled liquid back for heating. The use of this method on a particular object depends to a greater extent on the power of the boiler.
dead end
In this embodiment, the direction of supply of heated water and return is multidirectional. A two-pipe dead-end heating system involves the installation of batteries, each of which has an identical number of sections. To balance a system with such a movement of heated water, the valve installed on the first radiator must be screwed with great force in order to shut off.
Passing
This circuit is also called the Tichelman loop. An associated two-pipe heating system or just a ride is easier to balance and adjust, especially if the line is very long. With this method of organizing heating, each battery requires the installation of a needle valve or a device such as a thermostatic valve.
Horizontal
There is also such a type of scheme as a two-pipe horizontal heating system, which is widely used in one- and two-story houses. It is also used in rooms with a basement, where you can easily place the necessary communication networks and devices. When using this wiring, the installation of the supply pipeline can be done under the radiators or on the same level with them. But this scheme has a drawback, which is the frequent formation of air pockets. In order to get rid of them, the installation of Mayevsky cranes on each device is required.
vertical
A scheme of this type is more often used in houses with 2-3 or more floors. But its organization requires the presence of a large number of pipes. It should be noted that a vertical two-pipe heating system has such a significant advantage as the ability to automatically remove air that exits through a drain valve or expansion tank. If the latter is installed in the attic, then this room must be insulated. In general, with this scheme, the temperature distribution over the heating devices is carried out evenly.
Two-pipe heating system with bottom wiring
If you decide to choose this scheme, then keep in mind that it can be collector or with radiators mounted in parallel. Scheme of a two-pipe heating system with a lower wiring of the first type: two pipelines depart from the collector to each battery, which are supply and discharge. This model with the wiring of the lower type has the following advantages:
- installation of shut-off valves is carried out in one room;
- high level of efficiency;
- the possibility of installation in an unfinished object;
- overlapping and adjustment is carried out easily and simply;
- the ability to turn off the top floor if no one lives there.
With top wiring
A closed two-pipe heating system with an upper wiring is used to a greater extent due to the fact that it is devoid of air pockets and has a high water circulation rate. Before making a calculation, installing a filter, finding a photo with a detailed description of the scheme, it is necessary to compare the costs of this option with the benefits and take into account the following disadvantages:
- unaesthetic appearance of the premises due to open communications;
- high consumption of pipes and necessary materials;
- the appearance of problems associated with the placement of the tank;
- rooms located on the second floor warm up somewhat better;
- the impossibility of location in rooms with large footage;
- additional costs associated with decorative trim, which should hide the pipes.
Connecting heating radiators with a two-pipe system
Installation work related to the installation of double-circuit heating includes several stages. Radiator connection diagram:
- At the first stage, the boiler is installed, for which a specially designated place is prepared, for example, a basement.
- Further, the installed equipment is connected to an expansion tank mounted in the attic.
- Then, a pipe is drawn from the collector to each radiator battery to move the coolant.
- At the next stage, pipes for heated water are again drawn from each radiator, which will give them their heat.
- All return pipes form a single circuit, which is further connected to the boiler.
If a circulation pump is used in such a circuit system, then it is installed directly in the return circuit. The fact is that the design of the pumps consists of various cuffs and gaskets, which are made of rubber and do not withstand high temperatures. This completes all installation work.