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Designing and is a difficult task. When solving it, it is important to take into account all the existing nuances. First of all, you need to decide on the diameter of private houses or apartments. This is important for both one-pipe and two-pipe systems.

Selection of the pipe diameter, what will happen if you do not choose the right one?

When designing a heating circuit, it is necessary to minimize possible heat losses in order to reduce energy costs. An incorrectly designed system works ineffectively. The room temperature will not rise and the energy consumption will be excessive.

When taking into account not only the chemical properties of materials for the manufacture of channels, but also the indicator of their diameter. This indicator plays a critical role. How efficiently the system will work depends on it. The cross-section of the channels strongly influences the hydrodynamics. His choice should be given sufficient attention.

There is an opinion that the greater the cross-section of the channels, the better the carrier circulates in them. However, this is not at all the case. Excessive size of the diameter of pipes connected to gas or electric boilers leads to a decrease in pressure in the system. As a result, the radiators do not receive enough heat.

If you need to equip a heating circuit in a private house, you need to decide on the type of media supply. If the building is connected to a municipal heating main, the design and installation process will be similar to the arrangement of the system in an apartment.

An autonomous heating system can have various schemes. The choice of the channel cross-sectional index directly depends on them. The dimensions of structures for systems with natural type of circulation of the carrier differ from the options based on the use of pumps.

Main characteristics of pipes

All existing channels have several section parameters. You need to understand this. Otherwise, you can make a mistake and purchase exactly the designs that you need.

There are the following structural cross-section parameters:

• internal;
• external;
• conditional.

The key parameter is the inner diameter of the channel. On its basis, the calculation of the indicator of the throughput of the structure is made. The outer section is also taken into account when planning the contour. It is very important when installing the system. A conditional section is a rounded diameter indicator. As a rule, it is indicated in inches.

When choosing channels for creating a heating circuit, you need to understand that different measuring systems are used for products made from different materials. For example, structures are marked exclusively by the indicator of the inner section, and and by the outer diameter.

In addition, there are various types of plastic ducts.

Today the following types of polymer pipes are produced:

Plastic structures can have different technical characteristics. Reinforced polypropylene pipes are the most convenient for creating a heating system. But metal-plastic and polyethylene structures are also used to solve this problem. Before making a choice in favor of one or the other product, study its features in detail. This is the only way to choose the most optimal option.

Below, see the table of correspondence between pipe diameters made of different materials. She will help you make the right choice.

Correspondence table of outer diameters and nominal diameters of steel and polymer pipes

Most often, the section indicator is indicated in inches. This applies to all types of channels. Don't forget that one inch is 25.4 mm.

How to calculate?

For correct calculations, you need to take into account the magnitude of the heat load. It is believed that one hundred watts per square meter is enough to create a normal temperature regime in a room. This is true for rooms with a ceiling height of two and a half meters.

Thus, to heat twenty-five square meters, 2.5 kW of thermal energy is needed. The selection of channels can be done using the table below.

Based on the tabular data, half-inch structures should be used to heat rooms of twenty-five square meters.

Pressure and temperature in the heating system

When creating autonomous systems, you yourself determine the required temperature of the carrier in the loop. There is no approved norm. This indicator depends not only on environmental conditions and your own preferences, but also on the value of the heat transfer coefficient of the batteries. This parameter is the lowest y. Bimetallic products are characterized by the average value of the coefficient. The highest parameter is for batteries made of aluminum.

In principle, the specified temperature regime is optimal. But if the conditions of the external environment change, it needs to be changed up or down. Depending on the circumstances. Adjusting the temperature will allow you to create a more comfortable indoor environment and reduce energy costs.

If you choose polypropylene ducts to create a heating circuit, keep in mind that the temperature regime inside them should not exceed ninety-five degrees.

To make the system work more efficiently, it is better to increase the number of batteries or sections in them than to raise the temperature of the media above the specified mark.

Observe the pressure reading to ensure the normal functioning of the circuit. For autonomous systems, its value should be from 1.5 to 2 atmospheres. If the pressure rises higher, it can lead to an emergency. As a result, channels and other equipment will fail.

To monitor the pressure indicator, you need to use a pressure gauge. Expansion tanks will allow you to avoid the creation of an unacceptable pressure in the system.

System installation and wiring - installation

To build a heating circuit in a private house, you need to take into account some details. There are different wiring diagrams for the system. It is important to choose and design the most optimal option. The circulation of the carrier is natural and forced. In some cases, the first option is convenient, in others - the second.

Natural circulation occurs due to changes in the density of the liquid. Hot media has a lower density. The water heading back is denser. Thus, the heated liquid rises along the riser and moves along horizontal lines. They are mounted at a slight angle of no more than five degrees. The slope allows the wearer to move by gravity.

The heating circuit based on natural circulation is considered the simplest. You do not need to be highly qualified to carry out its installation. But it is only suitable for buildings with a small area. In this case, the length of the line should not exceed thirty meters. The disadvantages of this scheme are low pressure inside the system and the need to use channels of significant cross-section.

Forced circulation implies the presence of a special circulation pump. Its function is to ensure the movement of the carrier along the highway. When implementing a scheme with forced fluid movement, it is not necessary to create a slope of the contour. One of its disadvantages is the energy dependence of the system. If a power outage occurs, the movement of the media in the system will be impeded. Therefore, it is desirable that the house has its own generator.

Wiring happens:

• One-pipe.
• Two-pipe.

The first option is realized through sequential flow of the carrier through all radiators. This arrangement is economical. For its implementation, a minimum number of pipes and fittings for them will be required.

The one-pipe design has several disadvantages. You cannot adjust the media feed for each battery. The farther away from the boiler, the radiators will be less warm. You can overcome these defects.

To do this, you need to use the so-called "Leningrad" wiring diagram.

It involves the installation of by-pass pipes and shut-off valves on each radiator. This principle allows for uninterrupted media circulation when any battery is cut off.

Installation of a two-pipe heating scheme in a private house consists in connecting reverse and forward current to each radiator. This increases the flow rate of the channels by about two times. But the implementation of this option allows you to regulate the heat transfer in each battery. Thus, it will be possible to adjust the temperature regime in each separate room.

Two-pipe wiring is of several types:

• bottom vertical;
• upper vertical;
• horizontal.

Bottom vertical routing implies a supply loop on the floor of the lower floor of the building or its basement. Then, from the main line along the risers, the carrier goes up and enters the radiators. From each device there is a "return" that delivers the cooled liquid to the boiler. Implementing this scheme, you need to install an expansion tank. There is also a need to install Mayevsky taps on all heating devices located on the upper floors.

The top vertical layout is different. From the heating unit, the liquid goes to the attic. Further, the carrier moves downward through several risers. It goes through all radiators and returns to the unit along the main circuit. To remove air from this system, an expansion tank is needed. This scheme is more efficient than the previous one. Since there is a higher pressure reading inside the system.

The horizontal double-pipe type with forced circulation is the most popular.

It comes in three varieties:

• with ray distribution (1);
• with passing fluid movement (2);
• dead-end (3).

The radial distribution option consists in connecting each battery to the boiler. This working principle is the most convenient. The heat is evenly distributed in all rooms.

The option with passing fluid movement is quite convenient. All lines to the radiators are of equal length. The adjustment of such a system is quite simple and convenient. To install this wiring, you need to purchase a significant number of channels.

The last option is realized by using a small number of channels. The downside is the considerable length of the circuit from the far battery, which complicates the regulation of the system's functioning.

How to hide pipes

When building heating circuits, many owners think about how to hide heating pipes in a private house. This problem can be solved in different ways.

Most often, for the hidden installation of channels, they resort to:

• the use of decorated structures;
• the closure of the channels under the drywall;
• hiding products under false ceiling panels;
• installation under a raised floor;
• hiding structures in the walls of the building.

The choice of method depends on many factors. It is advisable to consult with specialists to solve this problem. There are many details to consider. Including the materials from which the building is made. It can be brick, aerated concrete, etc.

conclusions

When designing and installing heating systems, every detail must be taken into account. In this case, there are no trifles to which you can turn a blind eye. Mistakes made at the planning stage will lead to serious consequences. As a result, you will have to re-plan the circuit, dismantle the old system, and install a new one. The design phase should be carried out by a competent and experienced person.

The heating system in a private house can be with forced or natural circulation. Depending on the type of system, the methods for calculating the pipe diameter and selecting other heating parameters are different.

Related articles:

Calculation of the diameter of heating pipes is relevant in the process of individual or private construction. To correctly determine the size of the system, you should know: what the lines are made of (polymer, cast iron, copper, steel), the characteristics of the coolant, its way of moving through the pipes. The introduction of an injection pump into the heating design greatly improves the quality of heat transfer and saves fuel. The natural circulation of the coolant in the system is a classic method used in most private houses for steam (boiler) heating. In either case, during reconstruction or new construction, it is important to choose the right pipe diameter in order to prevent unpleasant moments in subsequent operation.

Pipe diameter is the most important indicator that limits the overall heat transfer of the system, determines the complexity and length of the pipeline, and the number of radiators. Knowing the numerical value of this parameter, one can easily calculate the possible energy losses.

Dependence of heating efficiency on the diameter of pipelines

The full operation of the energy system depends on the criteria:

1. Properties of a movable fluid (heat carrier).
2. Pipe material.
3. Flow rate.
4. Flow area or pipe diameter.
5. The presence of a pump in the circuit.

It is an incorrect statement that the larger the cross-section of the pipe, the more fluid it will let through. In this case, an increase in the lumen of the line will contribute to a decrease in pressure, and as a result, the flow rate of the coolant. This can lead to a complete stop of fluid circulation in the system and zero efficiency. If a pump is included in the circuit, with a large pipe diameter and an increased length of pipelines, its power may not be enough to provide the required pressure. In case of power outages, the use of a pump in the system is simply useless - heating will be completely absent, no matter how much the boiler is heated.

For individual buildings with centralized heating, the pipe diameter is chosen the same as for city apartments. In houses with steam heating, the boiler diameter must be carefully calculated. The length of the mains, the age and material of the pipes, the number of plumbing fixtures and radiators included in the water supply scheme, the heating scheme (one-, two-pipe) are taken into account. Table 1 shows the approximate losses of the coolant depending on the material and service life of the pipelines.

Table 1. Heat carrier losses

Pipe	Consumption m3 / hour	Speed ​​m / s	Head loss m / 100m
New steel 133х5	60	1,4	3,6
New steel 133х5	60	1,4	6,84
PE 100 110x6.6 (SDR 17)	60	2,26	4,1
PE 80 110x8.1 (SDR 13.6)	60	2,41	4,8
New steel 245x6	400	2,6	4,3
Old steel 245x6	400	2,6	7,0
PE 100 225x13.4 (SDR 17)	400	3,6	4,0
PE 80 110x16.6 (SDR 13.6)	400	3,85	4,8
New steel 630x10	3000	2,85	1,33
Old steel 630x10	3000	2,85	1,98
PE 100 560х33.2 (SDR 17)	3000	4,35	1,96
PE 80 560х41.2 (SDR 13.6)	3000	4,65	2,3
New steel 820x12	4000	2,23	0,6
Old steel 820x10	4000	2,23	0,87
PE 100 800x47.4 (SDR 17)	4000	2,85	0,59
PE 80 800-58.8 (SDR 13.6)	4000	3,0	0,69

Too small a pipe diameter will inevitably lead to the formation of a high head, which will cause an increased load on the connecting elements of the line. In addition, the heating system will be noisy.

Heating system wiring diagram

To correctly calculate the resistance of the pipeline, and, consequently, its diameter, the wiring diagram of the heating system should be taken into account. The options are:

• two-pipe vertical;
• two-pipe horizontal;
• one-pipe.

A two-pipe system with a vertical riser can be with top and bottom placement of lines. A single-pipe system, due to the economical use of the length of the lines, is suitable for heating with natural circulation, a two-pipe system due to a double set of pipes will require the pump to be included in the circuit.

Horizontal wiring provides 3 types:

• dead end;
• with a passing (parallel) movement of water;
• collector (or beam).

In a single-pipe distribution scheme, a bypass pipe can be provided, which will be a backup line for liquid circulation when several or all radiators are turned off. In the kit, shut-off valves are installed on each radiator to shut off the water supply when necessary.

Knowing the heating system diagram, it is easy to calculate the total length, possible delays in the flow of the coolant in the main (at bends, bends, in connections), and as a result - to obtain the numerical value of the resistance of the system. According to the calculated value of losses, the diameter of the heating mains can be selected according to the method described below.

Choosing pipes for a forced circulation system

The forced circulation system of heating differs from the natural one by the presence of a pressure pump, which is mounted on the outlet pipe not far from the boiler. The device operates from a 220 V power supply. It turns on automatically (via a sensor) when the pressure in the system rises (that is, when the liquid is warmed up). The pump quickly accelerates hot water through the system, which stores energy and actively transfers it to every room in the house through radiators.

Forced circulation heating - pros and cons

The main advantage of heating with forced circulation is the effective heat transfer of the system, which is carried out at a low cost of time and money. This method does not require the use of large diameter pipes.

On the other hand, it is important for the pump in the heating system to provide an uninterrupted power supply. Otherwise, the heating simply will not work with a large area of ​​the house.

How to determine the diameter of a pipe for heating with forced circulation according to the table

The calculation begins by determining the total area of ​​the room that needs to be heated in the winter, that is, this is the entire residential part of the house. The heat transfer rate of the heating system is 1 kW for every 10 sq. m. (with walls with insulation and a ceiling height of up to 3 m). That is, for a room with an area of ​​35 sq.m. the rate will be 3.5 kW. To ensure the supply of thermal energy, we add 20%, which gives a total of 4.2 kW. According to table 2, we determine a value close to 4200 - these are pipes with a diameter of 10 mm (heat indicator 4471 W), 8 mm (indicator 4496 W), 12 mm (4598 W). These numbers are characterized by the following values ​​of the flow rate of the coolant (in this case, water): 0.7; 0.5; 1.1 m / s. Practical indicators of the normal operation of the heating system - hot water speed from 0.4 to 0.7 m / s. Taking this condition into account, we leave for the choice of pipes with a diameter of 10 and 12 mm. Considering the water consumption, it will be more economical to use a pipe with a diameter of 10 mm. It is this product that will be included in the project.

It is important to distinguish between the diameters by which the choice is made: external, internal, nominal bore. As a rule, steel pipes are selected according to the inner diameter, polypropylene - according to the outer diameter. A beginner may be faced with the problem of determining the diameter marked in inches - this nuance is relevant for steel products. Conversion from inch to metric is also carried out through tables.

Calculation of the pipe diameter for heating with a pump

When calculating heating pipes, the most important characteristics are:

1. The amount (volume) of water loaded into the heating system.
2. The total length of the lines.
3. System flow velocity (ideal 0.4-0.7 m / s).
4. Heat transfer of the system in kW.
5. Pump power.
6. The pressure in the system with the pump off (natural rotation).
7. System resistance.

H = λ (L / D) (V2 / 2g),

where H is the height that determines the zero pressure (no pressure) of the water column under other conditions, m;

λ - coefficient of resistance of pipes;

L is the length (length) of the system;

D - inner diameter (the required value in this case), m;

V — flow rate, m / s;

g - constant, acceleration is free. fall, g = 9.81 m / s2.

The calculation is carried out for the minimum loss of thermal power, that is, several values ​​of the pipe diameter are checked for min resistance. The complexity is obtained with the coefficient of hydraulic resistance - to determine it, tables or a long calculation using the formulas of Blasius and Altshul, Konakov and Nikuradze are required. The final value of losses can be considered a number less than about 20% of the head created by the injection pump.

When calculating the diameter of pipes for heating L, it is assumed that the length of the line from the boiler to the radiators and in the opposite direction is equal, without taking into account duplicate sections located in parallel.

The whole calculation ultimately boils down to comparing the calculated resistance value with the pressure pumped in by the pump. In this case, you may have to calculate the formula more than once using different values ​​of the inner diameter. Start with a 1-inch pipe.

Simplified calculation of the diameter of the heating pipe

For a system with forced circulation, another formula is relevant:

D = √354 (0.86 Q / ∆dt) / V,

where D is the required inner diameter, m;

V — flow rate, m / s;

∆dt is the difference between inlet and outlet water temperatures;

Q is the energy delivered by the system, kW.

For the calculation, a temperature difference of approximately 20 degrees is used. That is, at the entrance to the system from the boiler, the temperature of the liquid is about 90 degrees, when moving through the system, heat losses are 20-25 degrees. and on the return line the water will already be cooler (65-70 degrees).

Calculation of the parameters of the heating system with natural circulation

The calculation of the pipe diameter for a system without a pump is based on the difference in temperature and pressure of the coolant at the inlet from the boiler and in the return line. It is important to take into account that the liquid moves through the pipes by means of the natural force of gravity, enhanced by the pressure of heated water. In this case, the boiler is placed at the bottom, and the radiators are much higher than the level of the heating device. The movement of the coolant obeys the laws of physics: denser cold water goes down, giving way to hot water. This is how natural circulation is carried out in the heating system.

How to choose the diameter of the pipe for natural circulation heating

Unlike systems with forced circulation, for the natural circulation of water, the overall cross section of the pipe is required. The larger the volume of liquid will circulate through the pipes, the more heat energy will enter the premises per unit of time due to the increase in the speed and pressure of the coolant. On the other hand, an increased volume of water in the system will require more fuel to warm up.

Therefore, in private houses with natural circulation, the first task is to develop an optimal heating scheme, in which the minimum length of the circuit and the distance from the boiler to the radiators are selected. For this reason, it is recommended to install a pump in houses with a large living area.

Yulia Petrichenko, expert

For a system with natural movement of the coolant, the optimal value of the flow rate is 0.4-0.6 m / s. This source corresponds to the min values ​​of the resistances of fittings, bends of the pipeline.

Calculation of pressure in a system with natural circulation

The pressure difference between the point of entry and return for the natural circulation system is determined by the formula:

Δpt = h g (ρref - ρpt),

where h is the height of water rise from the boiler, m;

g - acceleration of the fall, g = 9.81 m / s2;

ρot is the density of the water in the return line;

ρпт is the density of the liquid in the supply pipe.

Since the main driving force in a heating system with natural circulation is the force of gravity, created by the difference in the levels of water supply to and from the radiator, it is obvious that the boiler will be much lower (for example, in the basement of a house).

It is imperative to incline from the entry point at the boiler to the end of the radiator row. The slope is not less than 0.5 ppm (or 1 cm for each running meter of the line).

Calculation of pipe diameter in a natural circulation system

The calculation of the diameter of the pipeline in a heating system with natural circulation is carried out using the same formula as for heating with a pump. The diameter is selected based on the obtained minimum loss values. That is, first one value of the section is substituted into the original formula, checked for the resistance of the system. Then the second, third and further values. So until the moment when the calculated diameter will not satisfy the conditions.

How do you select the cross-section of the highway? What calculation method do you use? Please share in the comments.

Expertise - Estimating Engineer

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Pipe diameter for heating with forced circulation, with natural circulation: which diameter to choose, the calculation formula - print version

Ease of installation and high performance characteristics of polypropylene pipelines in water supply and heating systems are only the tip of the iceberg. For the correct operation of the installed communications, it is not enough to choose the type of polymer pipe and buy the material in the required quantity - preliminary design sketches are required, and for large objects - serious thermal and hydraulic calculations. For the heating system to be effective, polypropylene pipes for heating must have a diameter confirmed by these calculations.

Let us consider in more detail the significance of the size of the diameter of polypropylene pipes in the construction of pipelines.

Pipe material for communications. What are the parameters of the pipe

Questions of how the water supply system should look like, what diameter of pipes should be in the line that supplies heat to heating radiators, are solved at the design stage of life support systems in the house. As a result, the diameter of polypropylene pipes for water supply can often differ from the identical size of the heating system pipeline, since these communications have different purposes and are therefore exposed to different factors.

On a note: if the boiler water supply rate in the heating system pipeline is less than 0.2 m / s, then there is a high probability of airing the line, and exceeding the supply rate by 0.2 m / s will lead to an increase in costs - the cost of equipment exposed to large loads.

The use of polypropylene products has greatly simplified the work on equipping residential buildings with hot water heating and water supply systems. However, you need to know exactly which type of polymer pipe material is suitable in a particular case. The types of polypropylene pipes that exist today have different technical characteristics and are designed for a specific area of ​​use.

The most reliable products for the installation of hot water heating pipelines and hot water supply systems (DHW) are PN25 or PN30 products. It is these brands that are able to withstand pressures up to 25 and 30 atm. respectively, at the operating temperature of the coolant 950C. Even short-term operation of such pipes at a water temperature of 1200C is allowed, since thick walls are a distinctive feature of these products.

Samples of polypropylene pipes reinforced with aluminum.

The main article is about polypropylene pipes.

For cold water supply, polypropylene pipes with a uniform wall are used. For hot water supply systems and heating circuits, reinforced products are used, since the inclusion of an aluminum or fiberglass shell in the structure of the wall of a polypropylene pipe significantly increases the strength of the pipe material and reduces the amount of thermal expansion.

For reference: in reinforced pipelines, thermal expansion is 0.03 mm / m ° C, while for channels with a wall of homogeneous polypropylene this value is about 0.15 mm / m ° C. Based on this, homogeneous products are suitable for cold water supply, and only reinforced polypropylene is used for heating and hot water supply systems.

What diameters are polypropylene pipe materials produced?

When choosing accessories for a heating and water supply system, the decisive factors are the temperature of the liquid, its flow rate and pressure. The required cross-sectional area of ​​the water supply system is determined in this case by calculations performed in accordance with the scope and operating conditions of the equipment.

Based on the configuration of the pipe section (circular ring), its geometric parameters are determined by the outer and inner diameters. The current classification of polypropylene pipes clearly defines the typical dimensions of each type of pipe products used for installation.

Today, both domestic and foreign manufacturing firms produce standardized components for pipelines. Taking into account practical application, standard engineering solutions have been developed that allow determining the optimal passage in products for home heating and other water communications. Based on the data in the table, you can make the right choice of equipment and components for the heating main without resorting to hydraulic calculations.

As a rule, the marking contains one of the following values ​​for the outer diameter:

16, 20.25, 32 and 40 mm,

which correspond to the inner diameters of PN25 polypropylene pipes:

10.6; 13.2; 16.6; 21.2; 26.6 mm.

For ease of use, the correspondence of the diameters and wall thickness of polypropylene pipes used in heating and water supply systems are summarized in the table:

Table with data on the diameters and wall thickness of polypropylene pipes used in everyday life of the series Why are external parameters applied on finished products, if the size of the internal passage of the pipeline is so important for functionality. The point is that the outer diameter indicates the corresponding type of connection.

Potential of using polypropylene pipes of various outer diameters at a speed of movement of the coolant in the pipeline 0.7 m / s:

• a pipe with a diameter of 16 mm is designed to connect one or two heating radiators;
• a value of 20 mm corresponds to connecting up to 5 radiators with a total power of up to 7000 watts);
• for a larger number of radiators (with a total power of up to 11 kW), propylene polymer pipes with an outer diameter of 25 mm are used;
• polypropylene pipe material with an outer dimension of 32 mm is designed for equipping a house as a whole or one floor with a heating system of 10-12 kW of total power (maximum 19 kW);
• products with a diameter of 40 mm are used for laying trunk pipelines in residential buildings of a large area. Usually these are cottages and country houses, in which the number of heating devices reaches 20 pieces, and the total power of all connection points is approximately 30 kilowatts.

Influence of the pipe diameter on the performance of the heating system

The rate of supply of the coolant and the amount of transferred thermal energy directly depends on the inner section of the polypropylene pipelines. For clarity of this statement, the dependence of the provision of thermal energy on the intensity of the coolant supply and the values ​​of the pipeline diameters is summarized in the table:

Selection table for polypropylene pipe material depending on the rate of supply of the heat carrier and the need for heat energy Thermal power is indicated in W, the rate of supply of the heat carrier in kg / sec. The calculated data are based on average temperatures: the supplied heat carrier at 80 ° C, return flow at 60 ° C, air in the room + 20 ° C ..

For example: at a flow rate of 0.4 m / s, the following amount of heat energy will be transferred in the pipeline:

• for a line with an outer size of 20 (inner section 13.2 mm), the amount of heat is 4.1 kW;
• for propylene products Ø 25 and 16.6, respectively, the amount of heat will be 6.3 kW;
• propylene pipelines with outer and inner diameters of 32 and 21.2, respectively, have a heat supply of 11.5 kW;
• pipe materials of 40 millimeters (size of the inner lumen 26.6 mm) will provide a heat supply of 17 kW.

With an increase in the flow rate of the liquid to 0.7 m / s, the flow rate of the coolant will immediately increase by 70-80%.

Important! The practical purpose of the above table is to recommend, based on the value of the required amount of thermal energy, the required pipe diameter during the selection of pipe materials for a residential heating system.

Let's look at an illustrative example:

There is a typical house with a useful area of ​​250 m2. The building is sufficiently insulated and in order to create normal living conditions it needs heating at the rate of 1 kW per 10 sq. m, that is, to create a comfortable temperature in the house, 25,000 watts of thermal energy (maximum) will be enough.

Note: more heat is always required for the first floor - about 2/3 of the total consumed amount.

Thus, out of 25 kW, heating the first floor will require 15 kW, the second - 10 kW.

The house is equipped with an autonomous heating system based on a double-circuit boiler. The radiators installed in the rooms are connected in parallel. The house has a wiring for two wings with equal heat output. On the ground floor, the power for each wing is 7,500 watts. For the second floor, both wings require 5000 watts.

A two-storey house with a water heating system based on an autonomous boiler - cutaway This means that for the heating main you need to use polypropylene pipes and fittings with an inner diameter of 26.6 mm (at a feed rate of 0.6 m / s). This value corresponds to the outer diameter of the pipe 40 millimeters.

To supply the branches on the ground floor, 1500 watts of heat will be required. Using the data from the table, we get the following:

• at a flow rate of 0.6 m / s, the optimal diameter of the inner lumen of polypropylene pipes will be 21.2 mm - the corresponding external parameter corresponding to this value, according to the table, is 30 mm;
• for each wing, a pipe material with an inner diameter of 16.6 mm is suitable, which corresponds to a Ø 25 mm of the outer contour of the cross-section of polypropylene pipes.

Now we will consider the procedure for connecting heating devices.

Water heating radiators have an average power of 2 kilowatts, therefore, theoretically, pipes with a minimum outer diameter of 16 mm (PN16) are suitable for inserting them into the circuit. However, in practice, it is recommended to use polypropylene products with an inner section size of 13.2 mm and an outer diameter of 20 mm (PN20), since the use of polymer pipes PN16 is recognized as inappropriate due to low manufacturability.

The second floor is equipped with a 32 mm pipeline. Pipes and connecting fittings Ø25 mm are used for each wing. With radiators, the picture is the same as on the first floor - the batteries are connected using PN20 pipes.

Conclusion

Based on the above example, for each section of the pipeline in the heating system, you can select components of the required diameter - including the efficiency of the heating equipment will depend on this.

It should be remembered that the materials for the piping in the heating system are selected with the expectation of compliance with the maximum technical characteristics of an autonomous boiler, despite the fact that in most cases the unit will operate in normal mode - in accordance with the specified operating parameters.

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The choice of the diameter of polypropylene pipes according to the table: calculation of the diameter and the choice of heating pipes

The pipe selection procedure requires particularly careful attention, where many nuances must be taken into account. Among them, physical and chemical properties are important. The list should include both the length and diameter of the selected products. Maybe someone does not know, but such a characteristic as the diameter has a direct impact on the hydrodynamics of the entire heating system. The most widespread among pipe products used for private houses are structures with a diameter of about 16-40 mm.

A feature of pipes of this size is that they are able to cope with the pressure in the heating system. In addition to this, they demonstrate ease of use. The same can be noted in relation to the performance of installation work. With their help, you can effectively solve the problem of organizing the routing of the pipeline in an open way.

What is the inner diameter of polypropylene pipes used for heating

To determine the appropriate size, you can use the table or calculate the inner diameter of the pipes using the following formula:

d = √ (4-U-1000 / πL), where

U - parameter, which is defined as the total rate of water consumption in the house, which must be provided by the used water supply,

L is the speed of water flow, if tubular products of large diameter are used, then this parameter is determined by an indicator of 1.5-2 m / s, and for products with a small diameter - 0.7-1.2 m / s.

Most often, pipes based on polypropylene have an inner diameter of about 20-32 mm. If you plan to install a warm floor, then usually the choice is stopped on plastic structures, the diameter of which reaches 16 mm. In this case, it is necessary even before installation to understand how difficult the work will be, and with this in mind, select a material that can withstand all the loads. When determining the cross-section of the pipe, it is necessary to take into account many factors that are characteristic of the operation of heating systems.

Among the many characteristics, the most significant are considered to be:

• media temperature;
• flow rate;
• pipeline length;
• pipe diameter;
• hot water pressure.

It is widely believed that only if the inner diameter of the polypropylene pipes used in the heating system is correctly calculated, it is possible to ensure the most efficient and reliable operation of the system. When making mistakes in determining the size of a polypropylene pipe, there is a high probability that certain problems will arise during the operation of the system.

For example, choosing a diameter that is slightly larger than the required one, you may encounter a situation when the pressure in the heating system will not reach the optimal level, which will result in insufficient water circulation throughout all apartments in an apartment building. To ensure the correct operation of the system, it is necessary to competently carry out repair work, the essence of which is to install pipes with a suitable diameter.

How to choose the right diameter of a polypropylene pipe for heating

If the problem of organizing a heating system has arisen in a private house or cottage, then this issue must be resolved, taking into account the fact that the diameter will be constant only on the condition that a direct connection to the central heating system is made. If we are talking about using an autonomous system, then in this case it is allowed to use pipes of any size. Here the final decision must be made by the owner of the house.

When selecting blanks with suitable characteristics, all the nuances must be taken into account without fail. First of all, this concerns a situation when a natural heating system is used in the house, in which the cross-section and power of the pump will not play a decisive role. This feature is considered to be one of the advantages of this heating system.

Among the disadvantages of such a system, one should single out a small radius of action, as well as high costs for the acquisition of elements of a larger diameter, which will have to be used in such a situation.

For the system to work most efficiently, the owner must take care to maintain the optimum pressure level. Only if this condition is met, it is possible to ensure that the circulating coolant can safely bypass any obstacles in its path. Speaking about such barriers, first of all, we mean the situation with the friction of the liquid against the walls of the outlet or the tap of the heating device.

It should be noted that the length and diameter of pipeline elements directly affect the resistance and speed of fluid movement. If the coolant flows fairly quickly, and the pipes have a small cross-section and a significant length, this will lead to an increase in resistance on the path of the water.

The installation procedure for each heating system requires, without fail, the performance of such work as the development of a project diagram. Further, they are already beginning to prepare all the necessary materials and tools that will be required to perform the installation work:

• pipes;
• fittings;
• necessary tools.

After solving this issue, you can already think directly about installing polypropylene pipes.

When deciding on the choice of suitable elements, it is necessary to take into account the characteristics of the room, not forgetting about the type of heating. When carrying out preparatory activities, you must immediately assess the complexity of the work and relate them to your capabilities in order to understand how realistic this plan is to implement.

The fact is that not in all situations the owner is able to do this kind of work with his own hands. Sometimes some owners hesitate to take on such responsibility and simply invite qualified specialists.

When organizing heating systems, the owner has the opportunity to choose the following types of structures for the pipeline:

• polypropylene pipes;
• metal pipes;
• metal-plastic pipes.

Each of the listed products has its own pros and cons, due to the characteristics of the materials used for them. This point must be remembered without fail when the issue of choosing the appropriate option for your system will be resolved.

Among the proposed designs, the best are those made of propylene. Metal pipes have enough drawbacks, among which the high cost and the presence of difficulties in operation should be noted. An equally important disadvantage is their susceptibility to corrosive processes, which negatively affects their service life.

As for metal-plastic products, they differ in more affordable prices, do not create problems in use. However, in terms of reliability and durability, they are inferior to their polypropylene counterparts. For this reason, it is immediately necessary to abandon such a design option for a device based on heating systems.

Based on this, a conclusion suggests itself, which boils down to the following: the best solution for the system is polypropylene, since it is ideal for assembling pipes through which water will circulate.

It should be remembered that polypropylene structures are of different types: some are designed to circulate hot water, while others - cold. For this reason, it is necessary to choose the material taking into account the specific type of planned work.

For example, if you plan to lay pipes for heating, through which hot water will flow, then you should immediately abandon the use of structures designed for cold water for them. The fact is that in this case a different temperature regime will prevail, which, ultimately, will lead to violations of the operating conditions, and this may result in the occurrence of malfunctions in the system.

The advantages of polypropylene

If the owner solves the problem of installing a warm floor or a heating system in the house, then he, no doubt, can opt for polypropylene pipes. In many respects, such a solution is preferable due to the presence of many positive characteristics of these structures. Among the most significant are the following:

• reliability;
• long service life, which can reach 100 years;
• high resistance to corrosion processes;
• lack of mineral deposits;
• insensitivity to the effects of chemicals;
• no problems during assembly;
• design features allow for repair work in the event of a malfunction or breakdown;
• low cost.

Disadvantages of polypropylene

If we talk about the disadvantages that are characteristic of this type of materials, then first of all it is necessary to note the flammability and exposure to high temperatures.

When starting to organize a heating system in a house, it is very important to choose the diameter that the pipeline design will have. Moreover, you should not choose too large a diameter of polypropylene pipes, as this will negatively affect the operation of the system.

Installation of heating systems using polypropylene pipes

One of the important stages in the installation of a heating system is to resolve the issue with the scheme that will have to be adhered to when performing work. And if we talk about the use of polypropylene structures, then the following options can be involved:

1. The movement of liquid in the heating system by gravity. This option allows the owner to refuse to use the circulation pump, since the liquid in the system will flow naturally. A similar scheme can be implemented in rooms that are characterized by an unstable supply of electricity, which makes it very difficult to keep the pump running continuously.
2. Bottom filling system in heating. A feature of this scheme is the use of radial distribution, which is based on the use of a pump provided by an increase in the water pressure, which is achieved due to a smaller diameter.
3. A permissible scheme is in which one- and two-pipe systems are connected to a radiator, which is realized through a side or bottom connection type.

Installation of heating systems from polypropylene pipes

If you wish, you can do the installation of the propylene components of the pipeline system with your own hands, without resorting to the services of professionals. The procedure itself is performed by welding. Moreover, it is unacceptable to use threaded connections to fasten polypropylene elements together.

Even before the start of soldering, it is necessary to prepare the assembly components, cut them into fragments of the required length, for which special scissors are used. This must be done especially carefully to give the cut straight edges and to avoid burrs. This work takes a fairly small amount of time.

Welding works are carried out using the appropriate equipment, which is designed to carry out such operations. To connect the pipeline elements in this way, the pipe should be placed in a nozzle of a suitable diameter, after which it is heated, bringing it to a temperature of 260 degrees. The pipe heating procedure can take different times, this is primarily influenced by the diameter of the product. For example, if the pipe size is 20 mm, then heating for 5 seconds will be sufficient. With a larger diameter of the structure, which, say, has a size of 50 mm, it will take 18 seconds to heat up.

Conclusion

The device of a heating system in an apartment or a country house requires taking into account a large number of characteristics, among which the choice of the diameter for polypropylene pipes plays an important role. It is necessary to pay great attention to this point, keeping in mind that this will affect not only the ease of performing work on the installation of the heating system, but also the quality of its work.

Therefore, if you decide to do this work with your own hands, you must first of all prepare the necessary materials. Pipes should only be selected taking into account the future conditions of their operation, as well as the need to ensure sufficient circulation. Otherwise, not all consumers will receive enough water.

kotel.guru

Characteristics of polypropylene heating pipes

Polypropylene pipes, couplings and fittings

In this article we will look at polypropylene pipes for heating and their technical characteristics, which are indicated in the marking. Let's dwell a little on the materials that are used for production and reinforcement.

Materials and characteristics

Knowing the diameter is only half the battle, but when you come to the store, you will be faced with a variety of materials. Polypropylene pipes for heating comply with GOST R 52134-2003. They are made of three types of plastic, two of which can be used for hot water supply and heating systems:

• consisting of the same structural units. Their molecular bonds do not withstand heating, therefore, they are not applicable for systems with high operating temperatures;
• consisting of different structural units. The heterogeneity of bonds between molecules makes them resistant to heating, while the material does not lose its natural elasticity;
• consisting of crystals. They have the most durable and temperature-resistant structure while losing their elasticity.

In the marking of polypropylene pipes for heating, their outer diameter is indicated. Pay attention to this when you need to connect the contour of the apartment to the central riser. With an equal outer cross-section, metal and polypropylene pipes have a different internal nominal bore, for metal it is wider.

Be sure to choose reinforced products. Aluminum and fiberglass are used as reinforcing material. It is better to give preference to the latter, since during installation it is not necessary to remove the reinforcement layer to the depth of the connection of the contour with couplings and fittings. Reinforcement with aluminum is carried out:

• monolithic layer;
• a layer with multiple holes.

Reinforcement of polypropylene with perforated aluminum

Both the aluminum and fiberglass reinforcement layers are sandwiched between the two plastic layers. Reinforcement is only needed to compensate for the increase in length of the contour when heated. There is no question of strengthening the product, since the plastic is already very durable. Unreinforced products are not suitable, since they have a too high coefficient of linear expansion, which is 0.15 mm / m. For comparison, for reinforced products, it is 0.02 mm / m. Polypropylene pipes for heating have standard sizes. They are sold in lengths of four meters.

For clarity, let's make a calculation. Take one meter of a circuit in which water circulates, heated to 80 degrees. We multiply the temperature by the coefficient of linear expansion and get the following values:

• for reinforced products - 1.6 mm elongation;
• for unreinforced products - lengthening by 12 mm.

Also, the marking indicates the nominal pressure. It is designated by the Latin letters РN. For example, a product marked PN16 can withstand 16 atmospheres, but this is not the maximum of its capabilities. He can withstand a larger short-term increase. Nominal pressure is an indicator at which the service life of polypropylene pipes will be half a century. The calculation was carried out using special programs, where the water temperature is set equal to 20 degrees. This is important, as the temperature rises, the service life will, of course, be shorter, since, when heated, the plastic changes its mechanical characteristics.

Calculation of the diameter for central heating

In search of calculations, a lot of material was studied, often not giving a specific answer to the question of what size polypropylene pipes should be for heating. How to choose the diameter so that the system is balanced. In principle, in order to make accurate calculations taking into account all factors, you need to be a real specialist and get a specialized education. The calculation of the pipe diameter is included in the hydraulic calculation of heating, which is carried out using special profile programs. All other calculation methods will be approximate.

The thickness of polypropylene pipes for heating in private houses and apartments with central heating usually does not exceed 25 mm. Also use products 20 and 16 mm.

It's simple when you need to determine the diameter of a polypropylene pipe for heating in apartments with central heating. From the riser, passing through all floors, a branch pipe goes into each apartment. Its cross section, of course, is less than that of the riser itself. To correctly determine what diameter of polypropylene pipes is needed for central heating, you just need to choose the size of the cross-section for the branch pipe. Make sure that there is no narrowing of the contour. That's all, it's up to the choice of materials. Please note that the inner section must match, not the outer one.

Calculation of the diameter for autonomous heating

Questions about how to choose the diameter of polypropylene pipes for heating appear during installation

Calculation of the diameter of a polypropylene pipe for heating

circuits in private houses. We note right away that the calculations are approximate, but this does not mean that they are not correct. They can also be used on centrally heated apartment circuits. Determining parameters of the diameter of a polypropylene pipe for heating a private house:

• area of ​​the heated room.

It depends on how much heat is required to heat up to the required level. In order not to delve into the jungle of formulas, you can follow the general example and take into account 0.1 kW of energy per square meter, with a standard ceiling height of 2.5 m.Of course, you need to take into account the degree of insulation of the room, on the basis of which the heat loss coefficient is calculated. But in order not to get confused, just add 20% to the required number of kilowatts;

This indicator varies from 0.2 to 1.5 m / s. The higher the flow rate, the higher the pressure in the circuit. This often leads to the appearance of noise in the system, due to the friction of the coolant against the walls. To calculate the diameter of pipes, it is customary to use a value of up to 0.6 m / s - optimal for autonomous circuits of private houses. Because, what diameters of polypropylene pipes for heating are selected, the circulation speed also depends. The thicker the contour, the slower the water flows;

• difference between supply and return temperatures.

The indicator is quite individual. It depends on the power of the boiler, and on the material of the pipes, their insulation, as well as on the speed of the coolant. The standards determine that the supply is carried out at a temperature of 80 degrees, while the return flow will be about 60 degrees. The coolant cools down by 20 degrees, usually this value is taken into account.

What diameter polypropylene pipes should be used for heating a one-story house with an area of ​​80 square meters:

• the formula contains two constant values, multiplying which we get the value 304.44;
• then this number must be multiplied by 9.6 (80 square meters x 0.1 kW of energy + 20% of the reserve), it turns out 2100.636;
• the result is divided by 20 (temperature difference) and by 0.6 (m / s, coolant flow rate);
• at the end, we calculate the square root of the obtained value and get the value 13.23 mm.

Wall thickness of polypropylene pipes of different diameters

It turns out that the inner diameter of polypropylene pipes for heating a house with an area of ​​80 m2 is 13.23 mm. Note again that polypropylene pipes are marked on the outside. Also in the marking there is information about the wall thickness. You can calculate the conditional pass in one action, it's easier than a steamed turnip. You can also use the table of the ratio of pipe walls to their diameter.

Based on this, we can conclude that in this case a pipe with a diameter of 25 mm is suitable, since the twenty is a little undersized. For the calculation, we took the flow rate of the coolant 0.6 m / s, although a value of 0.2 m / s is allowed. Accordingly, by choosing a pipe with a larger cross-section, we reduce the circulation rate, while it remains within the standard.

Calculation based on the flow rate of the coolant

Diameter of polypropylene pipes for heating table:

The ratio of the diameter of pipes to the heat output of heating

There is a simple way to calculate the diameter of polypropylene pipes for heating - this is a table. Let's use it and make calculations for the same 80 sq.m. one-storey house. To heat it, you need 8 kW of energy, which equals 8000 watts. We find this value in the table and guide our eyes to the pink cells, which indicate the optimal speed of the coolant. In our case, these are 0.5 and 0.3 m / s. We stop our choice on the first value, which corresponds to a pipe with a diameter of 25 mm.

Now compare with the above calculation. As you can see, they coincide, which means that both methods for determining the diameter of pipes for heating are consistent and can be used for calculations. As a result, you should pay attention to the fact that it is better to adhere to the standards. Using pipes that are too narrow or too wide will have a negative effect on the performance of the system.

utepleniedoma.com

Choosing the diameter of pipes for heating: calculation scheme, characteristics depending on the material of manufacture

Correct design of a heating system is to take into account all possible factors affecting its efficiency efficiency. In addition to the correct selection of the main components, boiler, radiators, safety groups, the cross-section of the lines should be correctly calculated. To do this, you need to know the optimal diameter of heating pipes: how to choose the right one and calculate it yourself?

Difficulties in choosing the diameter of heating pipes

Heating scheme indicating the diameter of the pipes

It would seem that the choice of the diameter of pipes for heating a private house is not a difficult task. They must only ensure the delivery of the coolant from the source of its heating to the heating devices - radiators, batteries.

But in practice, an incorrectly selected diameter of the heating collector or supply pipe can lead to a significant deterioration in the operation of the entire system. This is due to the processes that occur during the movement of water along the highways. To do this, you need to know the basics of physics and hydrodynamics. In order not to go into the jungle of accurate calculations, you can determine the main characteristics of heating, which directly depend on the cross-section of the pipelines:

• The speed of movement of the coolant. It affects not only the increase in noise during the operation of heat supply, but is also needed for optimal distribution of heat among heating devices. Simply, the water should not have time to cool down to the minimum level when it reaches the last radiator in the system;
• Coolant volume. So, the diameter of pipes with natural circulation of heating should be large in order to reduce losses during friction of the liquid against the inner surface of the line. However, along with this, the volume of the coolant increases, which entails an increase in the cost of heating it;
• Hydraulic losses. If different diameters of plastic pipes for heating are used in the system, then a pressure difference at their junction will inevitably arise, which will lead to an increase in hydraulic losses.

How to choose the diameter of the pipe for heating so that after installation you do not have to redo the entire heating system due to extremely low efficiency? First of all, you should perform the correct calculation of the cross-section of the highways. To do this, it is recommended to use special programs and, if desired, manually check the result yourself.

At the junction, the diameters of polypropylene pipes for heating are reduced due to overlap. Reduction of the cross-section depends on the degree of heating during soldering and compliance with the installation technology.

The procedure for calculating the cross-section of heat supply lines

Before calculating the diameter of the heating pipe, it is necessary to determine their basic geometric parameters. To do this, you need to know the main characteristics of the highways. These include not only performance, but also dimensions.

Each manufacturer indicates the value of the pipe section - diameter. But in fact, it depends on the wall thickness and the material of manufacture. Before purchasing a certain model of pipelines, you need to know the following features of the designation of geometric dimensions:

• The calculation of the diameter of polypropylene pipes for heating is done taking into account the fact that manufacturers indicate the external dimensions. To calculate the useful section, it is necessary to subtract two wall thicknesses;
• Internal dimensions are given for steel and copper pipes.

Knowing these features, you can calculate the diameter of the heating collector, pipes and other components for installation.

When choosing polymer heating pipes, it is imperative to clarify the presence of a reinforcing layer in the structure. Without it, when exposed to hot water, the line will not have the required rigidity.

Determination of the thermal power of the system

How to choose the right pipe diameter for heating and should it be done without calculated data? For a small heating system, complex calculations can be dispensed with. It is only important to know the following rules:

• The optimum diameter of pipes with natural heating circulation should be from 30 to 40 mm;
• For a closed system with forced movement of the coolant, smaller pipes should be used to create optimal pressure and water flow rate.

For an accurate calculation, it is recommended to use the program for calculating the diameter of heating pipes. If they are not there, you can use approximate calculations. First you need to find the thermal capacity of the system. To do this, you need to use the following formula:

Where Q is the calculated thermal power of heating, kW / h, V is the volume of the room (house), m³, Δt is the difference between the temperatures outside and in the room, ° С, K is the calculated heat loss coefficient of the house, 860 is the value for converting the obtained values ​​into an acceptable kW / h format.

The greatest difficulties in the preliminary calculation of the diameter of plastic pipes for heating are caused by the correction factor K. It depends on the thermal insulation of the house. It is best taken from the data in the table.

As an example of calculating the diameters of polypropylene pipes for heating, you can calculate the required heat output of a room with a total volume of 47 m³. At the same time, the temperature outside will be -23 ° С, and indoors - + 20 ° С. Accordingly, the difference Δt will be 43 ° C. We take the correction factor equal to 1.1. Then the required thermal power is.

Q = (47 * 43 * 1.1) /860=2.585 kWh

The next step in choosing the diameter of a pipe for heating is to determine the optimal speed of movement of the coolant.

In the calculations presented, the correction for the roughness of the inner surface of the mains is not taken into account.

Water velocity in pipes

Table for calculating the diameter of the heating pipe

The optimal pressure of the coolant in the mains is necessary for the uniform distribution of heat energy over the radiators and batteries. For the correct selection of the diameters of heating pipes, the optimal values ​​of the speed of water advance in the pipelines should be taken.

It is worth remembering that when the intensity of movement of the coolant is exceeded, extraneous noise may occur in the system. Therefore, this value should be between 0.36 and 0.7 m / s. If the parameter is less, additional heat losses will inevitably occur. If it is exceeded, construction noises will appear in pipelines and radiators.

For the final calculation of the diameter of the heating pipe, use the data from the table below.

Substituting into the formula for calculating the diameter of the heating pipe into the previously obtained values, you can determine that the optimal pipe diameter for a particular room will be 12 mm. This is just a rough estimate. In practice, experts recommend adding 10-15% to the obtained values. This is because the formula for calculating the diameter of the heating pipe may change due to the addition of new components to the system. For an accurate calculation, you will need a special program to calculate the diameter of heating pipes. Such software packages can be downloaded in a demo version with limited calculation capabilities.

Calculation of the heating manifold and mounting sleeves

The above calculation technology can be applied to all types of heat supply - one-pipe, two-pipe and collector. However, for the latter, it is necessary to make the correct calculation of the diameter of the heating collector.

This heating element is necessary to distribute the coolant over several circuits. In this case, the calculation of the correct diameter of the heating collector is inextricably linked with the calculation of the optimal cross-section of the pipeline. This is the next stage in the design of a heat supply system.

To calculate the diameter of the heating manifold, you must first calculate the cross-section of the pipes according to the above scheme. Then you can use a fairly simple formula:

M0 = M1 + M2 + M3 + M4

Where M0 is the required collector diameter, M1, M2, M3, M4 are the diameters of the pipelines to be connected.

When determining the height and the optimal distance between the nozzles, the principle of "three diameters" is applied. According to him, the distance of pipes on the structure should be 6 radii each. The total diameter of the heating manifold is also equal to this value.

Sleeve for installation of heating pipes

But in addition to this component of the system, it is often necessary to use additional ones. How to find out the diameter of the heating pipe sleeve? Only after performing a preliminary calculation of the cross-section of the highways. In addition, you need to take into account the thickness of the walls and the material of their manufacture. The design of the sleeve and the degree of its thermal insulation will depend on this.

The value of the diameter of the sleeve for heating pipes is influenced by the material of manufacture of the wall, as well as the pipe. It is important to consider the possible degree of expansion when the surface is heated. If the diameters of the plastic heat supply pipes are 20 mm, then the same parameter for the sleeve must be at least 24 mm.

The installation of the liner must be done on cement mortar or a similar non-combustible material.

Additional data for calculating the diameter of heating pipes

After choosing the diameter of pipes for heating a private house, you need to choose the right material for their manufacture, and also take into account the features of the heating system. This parameter is influenced by the layout of the highways, as well as the number of shut-off and control valves.

In addition to knowing the diameter of pipes in heating with natural circulation, it is necessary to take into account the height of the booster riser and correctly select the size of its section. It should be at a minimum height of 1.5 relative to other heating elements. To increase the speed of movement of the coolant, the diameter of the polypropylene pipes used in the construction of the boost manifold must be one size larger than that of the main line.

Geometrical dimensions and weight of steel pipes

It is also important to consider the wall thickness of the pipelines. It depends on the material of manufacture and can vary from 0.5 mm (steel) to 5 mm (plastic). The choice of the diameter of pipes for the heating system of a private house is influenced by the material of manufacture. So, plastic lines are recommended to be installed for systems with forced circulation. Their inner diameter can vary from 10 to 30 mm. More information about the wall thickness of polymer pipes for heating can be found in the data in the table.

For steel models, it is necessary to take into account not only their geometric dimensions, but also their mass. It directly depends on the wall thickness. In programs for calculating the diameter of heating pipes, there must be a function for calculating the specific gravity of 1 lm. steel line.

Knowing these additional characteristics, you can make the most accurate calculation of the parameters of the heating system, including the correct selection of heating pipe diameters.

Heating pipe material

Construction of polymer pipes

In addition to the correct choice of pipe diameters for heat supply, you need to know the characteristics of their material of manufacture. This will affect the heat loss of the system, as well as the laboriousness of installation.

It should be remembered that the calculation of the diameters of heating pipes is carried out only after the choice of the material for their manufacture. Currently, several types of pipelines are used to complete heat supply systems:

• Polymeric. They are made from PP or XLPE. The difference lies in the additional components added during the production process. After calculating the diameter of polypropylene pipes for heat supply, you need to correctly select the thickness of their wall. It varies from 1.8 to 3 mm depending on the parameters of the maximum pressure in the lines;
• Steel. Until recently, this was the most common option for arranging heating. Despite their more than good strength characteristics, steel pipes have a number of significant disadvantages - complex installation, gradual surface rusting and increased roughness. Alternatively, pipes made of stainless steel can be used. One of their cost is an order of magnitude higher than "black" ones;
• Copper. In terms of technical and operational characteristics, copper pipelines are the best option. They are characterized by sufficient elongation, i.e. if water freezes in them, the pipe will expand for some time without loss of tightness. The disadvantage is the high cost.

In addition to the correctly selected and calculated pipe diameter, you need to decide on the method of their connection. It also depends on the material of manufacture. For polymer, a sleeve connection is used by welding or on an adhesive basis (very rarely). Steel pipelines are installed using arc welding (best quality connections) or threaded method.

How many pellets do you need to heat a house 100 sq. M

During the creation of heating systems, it is very important to accurately carry out all stages of work. Even at the design stage, you need to accurately determine the diameters of pipes for heating and their type. We will talk about how to choose the right cross-sectional pipes in a given situation below.

Is it really important to choose the exact cross-section of the pipe

When a heating system is being developed, for example, from PP pipes, they try to minimize all possible heat loss, that is, to reduce the amount of energy consumed. An incorrectly planned system will function at least ineffectively. As a result, the rooms will either remain cold, or an unreasonably large amount of energy will be spent on heating them.

When deciding what pipes for heating should be, they pay attention not only to their chemical properties and physical characteristics, but also to the length and section, since they also play an important role in the design of an effective system.

It turns out that the diameter of the pipe for heating a private house directly affects the overall hydrodynamics, which is why it is so important to take these parameters into account in order to obtain the best heating.

Quite often, unknowing people, in order to choose the diameter of the heating pipes, use the rule according to which the cross-section of the pipe should be as large as possible, thus making a gross mistake. In fact, from the fact that the water in the system will pass more freely, it will not function more efficiently, on the contrary, the pressure in the system will drop below normal, and the radiators will not heat up properly.

When choosing the diameter of a polypropylene pipe for heating a private house, first of all, you should decide on the type of coolant. If the house is powered from a common heating main, then the entire list of calculations is carried out according to the same principle as when arranging an apartment.

The size of pipes for heating a private house will be determined by the scheme used and the type of pipes. The cross-section of pipes, for example, for a heating system with natural water movement, will differ from the system in which the circulation pump will be installed.

The most important pipe parameters

All heating pipes have several parameters:

• First of all, this is the inner section. It determines the indicator of the throughput of the pipe.
• The outer section is also an important parameter that is taken into account when developing a system.
• Conditional section - that is, the rounded value, which is measured in inches.

When selecting pipes, you need to pay attention to the material of manufacture, since it can be different, and the system for measuring excellent products also differs. For example, almost all steel and cast iron pipes are marked for their inner diameter.

Another thing is pipes made of plastic and copper - their marking is carried out according to the external section. This is especially worth considering if you are going to create a system of pipes from several materials.

Please note that if the system is assembled from several materials, for the correct selection of their cross-sections, it will not be superfluous to take information from the cross-section correspondence tables, which can always be found on the Internet.

When deciding on the cross-sections of pipes for heating, it is worth remembering the system for measuring such quantities. The diameter is often expressed in inches. When translating expressions from one number system to another, remember that one inch equals 2.54 cm.

Calculation of the cross-section of pipes

It's time to find out how to calculate the diameter of pipes for heating. In this case, you will need to take into account the thermal load. Based on many years of practice, it turned out that to create comfortable conditions in a room, 0.1 kW of thermal power is required per 1 m 2 of area - this is taking into account the fact that the ceilings in the room are 2.5 m high.

In other words, to heat a room of 25 m 2, you will need 2500 W of thermal energy (25 · 100 = 2500 W).

Normal indicators of pressure and temperature in pipes

Having installed autonomous heating, the owner himself controls the temperature, choosing the most acceptable for himself. It is worth noting that in this case there are no accepted norms, because the temperature is determined not only by external factors, but also by the preferences of the owner, and the efficiency of the installed heating radiators.

Please note that cast iron radiators have the worst heat transfer. The average heat transfer coefficient is for bimetal radiators, and aluminum radiators are considered the most efficient.

Often, the calculation of the number of radiators and sections is carried out taking into account the passport thermal power. This parameter is determined based on the temperature of the water in the pipes, which is 75 ℃.

In other words, reasoning logically, the indicated temperature will be the most optimal. Nevertheless, with fluctuations in external temperatures, it will be necessary to change the temperature of the coolant. Thus, it will be possible to maintain a comfortable room temperature and save energy.

To increase the temperature in rooms, it is best to install more radiators, rather than increase the temperature of fewer.

For the heating system to function correctly, the owner must know what the pressure should be in it. If the system is autonomous, 1.5-2 atmospheres will be satisfactory. If these indicators in any way rise to 3 atmospheres, then we can consider that the situation is critical, and the loss of the system of tightness, as well as equipment breakdown, is not excluded.

To be able to control the pressure in the heating system at any time, at the design stage, it is worth including a pressure gauge in the circuit. And to reduce excess pressure, it is best to equip the system with expansion tanks.

Finally

In conclusion, it would not be superfluous to say that at the design stage it is worth considering all the nuances, even those that may seem unimportant. A mistake made at this stage can be costly, at least the finished system will not be able to function properly, that is, it will be ineffective.

That is why it is best to entrust the development of projects to professionals who are able to carry out all the calculations correctly, so that the finished system works correctly.

The abundance of various materials and systems that currently exists on the pipe market is not easy even for a specialist to understand. A particularly difficult and responsible matter is the choice of pipes for heating. After all, an incorrect calculation will either lead to an overspending of the energy carrier, or - to the cold in the house.

An accident in the heating system can lead to even worse consequences. How not to be mistaken when designing your system - later in the article.

Criterias of choice

In fact, the process of choosing a specific type and type of pipes can be divided into two equivalent parts: which pipes to choose for heating according to the material, and then which diameters will be required. In principle, this problem can be solved from both ends. The required diameter depends on the throughput of the pipe and the wiring diagram, but pipes of different diameters from the same material, and especially fittings for them, can differ in price at times.

Therefore, the future homeowner must decide what is of paramount importance to him: the final price of the system, or the requirements for the size of the pipes.

Materials market

All existing piping systems can be divided into two large groups:

Metallic

• "Black metal
• Stainless steel
• Copper, brass, bronze

Galvanized steel is used much less often, in isolated cases - titanium, aluminum, other non-ferrous metals and alloys.

Polymer

• Polypropylene
• Polyethylene
• Metal-plastic

Moreover, in the group of polymers, in fact, the structure is much more complicated than this simple classification. Indeed, in addition to the fact that each material itself has several modifications, it can also have several layers.

For this it is clear from its name, but even here everything is not so simple. It is a three-layer material of aluminum foil sandwiched between two layers of polymer.

The material itself is either cross-linked polyethylene (PEX) or polypropylene (PP), but in each of these cases there are still several varieties, depending on the method of making the plastic and its class.

Advantages and disadvantages

None of the materials are perfect, and have their drawbacks. However, there are also such materials on the list, the properties of which force them to leave the market. PVC is practically not used for heating due to the low operating temperature limit.

Not far from it, for the same reason, polypropylene. Actual candidates for which pipes to choose for heating are:

Metal-plastic

It is a very high performance material (if it is of the proper quality). It has practically the lowest resistance to water flow. It is easy to install and can withstand temperatures of 90-100, and in short-term surges - 110-130 ° C, which are practically unrealistic in individual heating systems.

An added benefit is its flexibility. In addition to the fact that it can be hidden in walls or behind furniture, it allows you to lay long continuous sections of any shape, with any turns. None of the other materials can boast of this.

Polyethylene

It is a part of metal-plastic pipes, but in the absence of a foil layer it loses an important quality - thermal stability.

As a result, when heated, the pipe stretches, and therefore requires additional fasteners, and in long sections - compensation loops, which take on the bending of the pipe when it is pulled out from the effect of temperature. The rest of the pipes are roughly similar to metal-plastic.

Important information!

Before deciding which pipe to choose for heating, you should consider: not every polyethylene is suitable for this purpose.

It must have a special anti-diffusion layer that prevents the suction of atmospheric air.

Otherwise, air will accumulate in the system, creating noise, disrupting its efficiency, and sometimes even its performance.

Any types of plastic also have another advantage: they are good sound insulators, so they almost never make noise.

Copper

- an excellent solution, they are not inferior to metal-plastic, and even surpass it in many respects, and it is copper, when deciding which pipes to choose for heating, should come first - especially in terms of durability (up to 100 years).

However, the comparative disadvantages include its high thermal conductivity (although, for example, for a "warm" floor, this is even an advantage) and, most importantly, a high price.

Stainless steel

A somewhat exotic material preferred by lovers of "chrome" exotic. It is somewhat cheaper than copper, but lacks its flexibility and thermal conductivity.

Installation of stainless steel systems has its own characteristics and is somewhat more complicated than other materials

Important information!

When installing systems "warm" floor, as for the pipes for heating, the choice is very limited. It must meet two requirements: either it must not have seams in the concreted part, or such seams must be connected with press fittings.

These conditions are met only by copper and metal-plastic. There are press fittings for stainless steel, but considering how many of them are required to lay all the zigzags of the system, even copper will cost several times cheaper.

Instrumental question

If you install the system with your own hands, the necessary tool can play an important role in the question of which pipe for heating to choose. Indeed, almost each of the types of pipes requires specific equipment for installation, which is very expensive.

Moreover, even if there are press fittings from any manufacturer, it is not a fact that a crimper from another company will allow them to be crimped with high quality. The same goes for soldering machines for polyethylene. This means that, perhaps, it will not be possible to rent the equipment.

This requires very specific skills and a clear knowledge of the production technology, so experts do not recommend taking on this operation without the appropriate qualifications.

There are nuances in polyethylene welding. All these points should also be considered and taken into account before finally choosing pipes for heating. In this sense, the most democratic system is the connection on split rings, it is also called "O-ring".

It does not require tools, except for a pair of wrenches, preferably adjustable, and all the necessary skills are the ability to turn the nuts. However, of all types of connections among plumbers, it is considered the least reliable. Although its undoubted plus is that it can be considered conditionally collapsible.

Heat engineering calculation

If the question, which pipes for heating to choose, in terms of material has already been decided, it is time to calculate their size.

It is carried out based on the following parameters:

• Selected wiring diagram
• Pipe resistance coefficient to heat carrier flow
• Inner pipe diameter
• The speed of movement of water in the system
• Estimated water cooling in radiators
• Boiler inlet and outlet diameters (they are always the same)
• The amount of heat required to transfer

Important information!

Thermal calculation is a complex engineering task. In cases of complex systems, with many radiators, or mixed systems, a radiator-warm floor, it is better to order the project to a specialist, he will also tell you how to choose pipes for heating.

Otherwise, it will take a lot of effort and money to correct errors.

From the above list, the following indicators are normative:

• V - The speed of movement of water in the system - should not exceed 1.5 m / s
• T - Estimated water cooling (difference at the exit from the boiler and when returning to it) - 15-20 ° С
• Resistance coefficient - given by the manufacturer
• Boiler inlet-outlet diameter - factory characteristic
• Q- The required amount of heat is the total power of radiators or underfloor heating system
• Water consumption C = 0.86.Q / T

However, the data that can be obtained in this way are still approximate, and their adjustment depends on many factors.

Further, the system is designed as follows: the inlet-outlet of the boiler is taken as the starting point, the diameter of the pipe for heating is based on the rule that it cannot be larger than the corresponding parameter of the boiler.

The initial section, at least one and a half meters long from the outlet, even in polymer systems is made of metal, and continues with its corresponding diameter until the first branch of the pipeline.

Important information!

In heating systems, all diameters are considered as internal, for example, a 16 mm pipe made of metal-plastic has an internal diameter of 12 mm.

Therefore, the outer diameters of metal and polymer pipes obviously do not coincide!

Next comes the routing of the pipeline branches. Here, the choice of the diameter of the pipe for heating depends on its length, but, as a rule, each subsequent branch is one step less than the previous one: if a central pipe with an inner diameter of 24 mm comes out of the boiler and then divides into two branches serving different groups of radiators, then the diameter of these branches will be 18 mm.

They run with this diameter along all devices, where a 12 mm connection is connected to each of them. On the last device, the branch also ends with a 12 mm pipe. If there are a lot of devices, then they are divided into a larger number of branches connected to the central pipe. The chilled water pipeline is connected in the same way, but this time to the boiler inlet.

In general, the heat engineering calculation is one of the most difficult in construction, and not every certified specialist can perform it with high quality. Therefore, it is better for the householder to limit the choice of pipes for heating with the preferred material. However, if you have the time and desire, you can always find the right formulas and try to figure out the intricacies of heating technology yourself.