Heating with plastic pipes in a private house. Features of using metal-plastic pipes for heating
In this article we will talk about an autonomous home heating system. If you are well versed in engineering networks and technology, and also like to create with your own hands, then why not build this heating system yourself, which will significantly save the family budget. This article will tell you about many of the nuances that you will encounter in the process.
Think a few times before doing the installation, as the consequences may be a burst pipe with boiling water or a frozen house.
If gas is supplied to your house, then it is advisable to choose a gas boiler with automation, protection and a pump.
- To heat a house with your own hands, an average house will be quite enough for a boiler for 30,000 rubles Baxi Eco Four.
- If there is no chimney, then it is better to choose a boiler with a closed combustion chamber, and use a coaxial pipe to remove gases. Tona can be brought out through the wall of the house, and you save on the installation of the chimney.
- Wall-mounted boilers are distinguished by their own automation and protection elements, so think about a voltage stabilization unit, proper installation of the coaxial pipe and the boiler itself.
- If your plumbing system has more than 100 liters of water, then you will need to install an additional expansion tank to help you compensate for the expansion of water when heated. Otherwise, the pressure in your system will increase by more than 3 mbar.
We use an electric boiler when heating a house with our own hands
If, for home heating, you decide to use an electric boiler, then make sure that it is equipped with a pump, built-in automation, an expansion tank and a security group.
- Such a device will save you a lot of time and nerves, as well as eliminate errors during installation.
- If you use a conventional boiler, such as EVAN, then you will have to install a safety group on the supply pipe, and an expansion tank and pump on the return pipe.
If you decide to use a solid fuel boiler, then you will be able to install it only with certain knowledge of welding. Of course, you can use plastic pipes in the boiler, but in this case you will have to develop a piping scheme, since the temperature during heating can rise to more than 100 degrees.
How to choose material for heating
When you determine the source of heat in the house, you can start choosing the radiators themselves.
Plastics are by far the most suitable materials for self-arrangement of heating systems.
Steel ones still require better quality, while copper ones are very expensive to install. You will choose from metal-plastic or polypropylene.
Do-it-yourself metal-plastic for heating a private house
1. This material is very convenient and easy to install and is quite suitable for implementing your own heating system with your own hands. Metal-plastic on compression fittings does not require special equipment at all. You only need to stock up on wrenches, flares and pipe bending springs. Their disadvantage can be considered the high cost of fittings, as well as problematic bending into a straight line. The downside of the fitting can be considered a rubber seal. Hot water quickly degrades rubber, and turning off the heating during the summer months also has a negative effect on durability.
Perhaps after 5 years you will have to replace or tighten some connections. It is very important to buy a really high-quality product, which is available only from official dealers.
2. Metal-plastic on press fittings is more reliable. They can be hidden in niches, walls, if only the installation is carried out with high quality. At a water temperature of no more than 80 degrees, they will last a very long time. Their downside is the really high cost of the press tool and the fittings themselves.
1. Today, polypropylene is the market leader in terms of sales. This material is quite inexpensive, but can last for many years if you follow the rules of operation.
- To work with such material, you need to buy a soldering kit (price from 1500 rubles).
- Soldering polypropylene requires an assistant.
- The main thing is to make sure that it does not overheat and is firmly fixed for 10 seconds after soldering.
- This material is not at all afraid of defrosting the system, but remember about the boiler and expansion tanks, which can fail at any moment.
If you have never had to solder polypropylene, then you need to learn special instructions.
To create a truly high-quality system, you can turn your attention to Vesbo Turkey. They are ideal for any heating system.
2. Weld polypropylene pipes at a temperature not lower than +5 degrees. At lower temperatures, you need to create a special thermal zone.
Possible heating schemes
You can conduct water to radiators in different ways - do-it-yourself manifold, one- and two-pipe heating systems.
- The single-pipe scheme assumes that the radiators are heated in a condescending manner, that is, each subsequent battery will be colder than the previous one. This scheme allows you to significantly save the cost of pipes, but it does not distribute heat well.
- The collector circuit assumes a large length of pipes, but you can evenly and easily distribute heat throughout the house.
- The best option would be a two-pipe method of installing the system.
For example, we use a two-pipe wiring for a house with an area of \u200b\u200babout 100 square meters.
- Metal-plastic pipe with a diameter of 20x2.
- Ball valve.
- Straight valve.
- Membrane tank for heating, 18 liters.
- Circulation pump with nuts.
- Check valve 1 or 2 inches.
- Security group.
- Radiator.
- Adjustment valve.
- Adjustment valve.
- Radiator plug.
- Mayevsky crane.
If, for heating the house with your own hands, you decide to use a boiler with a built-in expansion tank, a safety group and a pump, then you can ignore positions 4-7.
There must not be any control or shut-off valves between the safety group and the boiler.
If you use polypropylene, then you need to take into account that metal-plastic with a diameter of 20x2 corresponds to reinforced polypropylene with a diameter of 25x4.2, and a pipe of 20x3.4 corresponds to a diameter of 16x2, a polypropylene pipe 32x5.4 corresponds to a diameter of 26x3.
To bring them to the radiators from the main pipeline with a two-pipe system, you need to use polypropylene with a diameter of 20x3.4, you can also use metal-plastic with a diameter of 16x2.0. It is not justified to use pipes with a larger diameter or to use radiator valves more than ½. It is a mistake to assume that the larger the thermostatic valve and pipe, the better it will heat the radiator.
The last radiator should be located at a distance of no more than 25 meters with a power of up to 12 kW. This suggests that for the high-quality operation of the system, you need to connect no more than 6 radiators with 10 sections. If you use more radiators, then, accordingly, the length of the pipes will increase, and this, in turn, will affect the deterioration in the uniformity of heating of distant radiators.
If you want to connect a lot of radiators, or increase the length of the pipes, then you will have to use pipes with a large cross section - 26x3 metal-plastic, or 32.5 polypropylene. You can also create two heating circuits.
A deep filter can be installed directly in front of the pump, which will protect your pump from large metal particles. In order for the filter to work efficiently, you need to install it on a horizontal section of the pipe.
In each apartment of a multi-storey building, to create the optimal temperature, it is possible to connect to centralized heating.
For the normal functioning of all elements of the system with its independent installation, it is necessary to competently approach the choice of material and the installation of individual elements.
Do-it-yourself heating from metal-plastic pipes is the easiest, fastest and cheapest to do. Here you only need to have a certain set of tools, familiarize yourself with the main characteristics and types of material, and also follow the installation instructions for the system.
Features and types of metal-plastic pipes
This type of pipe has the same structure, regardless of the marking and manufacturer.
In cross section, two layers of plastic are visible, between which is an aluminum sheet.
The marking text contains the following data:
Advantages and disadvantages of metal-plastic pipes for heating
Before deciding on the material, it is recommended to pay attention to the main advantages and disadvantages of metal-plastic pipes for heating.
The positive qualities include good whip flexibility, excellent anti-corrosion properties, low cost and easy installation. Also, the advantages of the material include the ability to withstand water heating up to 95 degrees.
Of the negative features, several important features of metal-plastic stand out:
- Relatively short service life. It is no more than 15 years;
- The reliability of connections is lower than metal and plastic counterparts;
- When the liquid freezes, the heating system becomes unusable, as the pipes burst.
All these shortcomings contribute to the low price of metal-plastic pipes for heating, so you should not build on this factor.
The main stages of pipe installation
The first step is to carry out preparatory work. This includes removing old pipes or marking the walls when the system is first installed, determining the required amount of material and fittings. You should also immediately buy metal-plastic pipes for heating and stock up on tools.
For installation of heating you will need the following kit:
- Calibrator that gives the ends a perfectly round shape;
- Scissors for cutting pipes into segments of the desired length;
- Fittings are installed using an adjustable wrench;
- Special spring for pipe bending;
- Sealing of all connections is ensured by the use of fum-tape.
Three types of fittings are allowed to connect individual pipe sections:
- Detachable. A threaded connection is used here, which makes it possible to reuse parts;
- Conditionally detachable fittings. These compression parts require replacement of the ferrule when reinstalled;
- One-piece. For such fittings, special pressing equipment is required, which compresses the steel shell of the part, creating a reliable tightness of the connection.
Key installation requirements
- At the time of installation of the system, the air temperature in the room must be above 5 degrees;
- Pipes are attached to the wall with clips, which must be larger in case of thermal expansion of the material;
- Do not break the aluminum layer when. This requires a special spring. If the bending radius exceeds the value of 7 pipe diameters, then it is recommended to use fittings;
- In the case of a threaded connection, it is desirable not to pinch the material to prevent leakage and destruction of the plastic.
Compliance with all the rules will make the installation of heating quick and easy, and the system will serve for many years.
Many people are interested in the question: “How do you do the wiring of the heating system pipes in a country house with your own hands?” I will try to convey to you the simplest scheme using a specific example of a house. I’ll just make a reservation right away, this material can only be considered as an introductory document, and the installation of heating systems should be completed by professionals who have the appropriate education and a package of permits for this.
Figure 1. Floor plan of the house.
Now let's define the key materials. Our heating system should be budget-friendly and easy to install. We will use metal-plastic pipes. Unlike polypropylene or PEX pipes, metal-plastic pipes do not require special tools, with the exception of a pipe cutter and a pipe bending spring. But these tools are not so expensive and worth it. We use tees, angles and other fittings - threaded, so that it can be tightened in which case with a simple wrench. You can use any radiators, but we will mean the use of aluminum sectional ones. Piping - external, along the wall near the floor.
Figure 2. Spring for bending a metal-plastic pipe and a pipe cutter.
Heating scheme.
In this project, it is optimal to use a two-pipe wiring. One pipe is supply, the other is return. Bottling is independent for each floor. This means that two pipes are led to the first floor and two pipes to the second. The resulting four pipes are led to where the waterworks with a boiler will be installed. It is possible to interconnect two supply and two return flows, respectively, and then bring them to the boiler through one common pump. But the performance of such a system is questionable due to the sufficiently large number of consumers.
In order for the coolant flow and heat distribution over the radiators to be uniform, we will reduce the diameter of the pipe after each radiator (with the exception of the end radiators). Installation of heating systems using this method is most common along with beam wiring. Beam wiring has some advantages, but is significantly more expensive due to the high pipe consumption. Based on all of the above, we obtain a two-pipe circuit shown in Figure 3.
Figure 3. Two-pipe heating system wiring diagram.
Materials for heating.
- Pipe d32: 2*3m (ground floor) + 2*3m (lift to the second floor) + 10% (reserve). Total average required 15 m. (See also:)
- Pipe d26: 2*8m (first floor) + 2*6m (second floor) + 10% (reserve). Total 31 m.
- Pipe d20: 2*10m (first floor) + 2*10m (second floor) + 10% (reserve). Total 44 m.
- Pipe d16: 2 * 8m (first floor) + 2 * 10m (second floor) + 15 * 1m (supply to radiators according to the number of radiators) + 10% (reserve). Total 56 m.
- Tees can be identified according to the scheme: 26x32x26 - 4 pcs., 26x16x26 - 8 pcs., 26x16x20 - 8 pcs., 20x16x16 - 8 pcs. You will also need 4 adapters from d32 pipes to threads in the boiler room. You also need 15 valves for the inlet to the radiator and 15 for the outlet. It is better to take corner valves, so that it is more convenient to attach a pipe to them. To switch from a d16 pipe to a valve thread, 30 adapters d16x3/4” or d16x1/2” are required, depending on the diameter of the purchased valves.
- Mounting clips are taken at the rate of one clip per 1..1.5 m of pipe.
Installation order.
Pressurization is carried out as follows. Connect a pump to the supply pipe through a drain valve, which pumps the coolant into the system. In this case, the drain valve on the return must be open. Pump coolant until it flows from the return. Turn off the return valve. Then pump until the pressure in the system reaches 3 bar. Stop the pump. Bleed air from all radiators. At the same time, keep an eye on the pressure. If it falls below 1 bar, then it is necessary to raise it with a pump. Having bled air from all radiators, bring the pressure to 2-3 bar and close the drain cock on the supply pipe. Your system is now pressurized. After the first heating cycle, the heating system may leak, so it is necessary to check all joints and, if necessary, tighten them, as well as re-bleed the air from the radiators. Pressure testing of the boiler room and start-up of the boiler should be carried out by a specialized organization.
About which pipes are better for heating, metal-plastic or polypropylene, disputes have been going on for more than one year. Both technologies have adherents. What is metal-plastic pipes? In structure, they are similar to aluminum-reinforced polypropylene ones: a layer of aluminum foil is glued with adhesives to two layers of polymer - inner and outer. The strength of the whole structure depends on the quality of the glue used, and the characteristics depend on the plastic: mode of use (ambient temperature), durability, degree of chemical neutrality to the transported medium.
MP pipes differ in the method of joining the foil: there is an overlapping technology, and there is a butt, by welding. All leading companies that produce quality products use the butt welding method. This requires expensive and complex equipment, but such a seam is much more reliable. When welding with an overlap, it will not work to bend the pipe normally - the seam interferes: it either cracks or folds into an accordion, and even with constant increased pressure, such a seam collapses faster. In principle, in this case, you can not bend pipes, but use fittings in all the right places, but then the wiring turns out to be much more expensive: each fitting costs decently, and even taking into account the fact that pipes with an overlap seam are almost two times cheaper than products with a welded seam, there will be no savings.
Advantages and disadvantages of metal-plastic pipes
Let's start with virtues:
Now limitations:
Most of the shortcomings can be attributed, rather, to the features and rules of operation: hide from ultraviolet radiation, do not use for high-temperature environments, make compensators and protect from fire (flammability). But the rest is not very pleasant. The need to tighten the connections is especially not encouraging: sooner or later there comes a moment when there is nowhere to tighten it. And then there is only one thing left: to change. To begin with, a fitting, and then, possibly, the entire system.
Features and Specifications
In principle, having already looked at the cross section of the pipe, you can to some extent determine whether it is of high quality or not: if the seam is welded and the thickness of the metal and polymer is the same everywhere, this is already a good sign. Also, the inner surface of the pipe must be uniform and smooth: so that deposits cannot accumulate in it.
Specifications MP
Dimensions and parameters:
- wall thickness 2-3mm;
- outer diameter: 16-63mm;
- aluminum layer 0.2-0.7mm;
- permissible bending radius:
- with manual bending 80-550mm;
- using a pipe bender 50-180mm.
The thickness of the aluminum layer is one of the most important characteristics. It determines the degree of tolerance of the internal pressure of the pipe and largely determines the area of \u200b\u200buse.
An important parameter of a metal-plastic pipe is the thickness of the aluminum foil
For example, the leading manufacturer of metal-plastic pipes, the Swiss company Henco (Henko), produces two types of products (generally more, but consider two): Henco RIXc and Standart. In the first series, pipes of three diameters (16mm, 20mm, 26mm) and an aluminum layer thickness of 0.4 (diameter 16 and 20 mm) and 0.5mm (diameter 26mm). In the Standart series, the diameters are larger - 20mm, 26mm, 32mm and the wall thickness is 0.5mm (pipe diameter 20mm) and 0.7mm for the other two. So, pipes with an aluminum thickness of 0.4 mm can be used for hot water supply, and all the rest for heating. If the thickness of the aluminum layer is 0.2 mm, they can only be used for cold water, and with a thickness of 0.3 mm and 0.4 mm - only for hot water. In any case, this is what Henco experts recommend.
Operating conditions:
- Operating temperatures
:
- Constant temperature +95 о С;
- Peak loads +110 о С;
- Freezing 40 o C.
Such characteristics are more than enough for any heating system: a centralized one is unlikely to give out above 95 ° C. There may be some surge, and even then at the end of summer, during start-up for a couple of hours. In the rest of the period you will not wait for such a temperature. In individual heating systems, you set the parameters of the system yourself. So here everyone is his own boss. The exception is systems that work with conventional solid fuel boilers - here, most likely, only metal pipes will be required (if there is no automatic control or a heat accumulator).
- Pressure:
- at an ambient temperature of 95 ° C to 10 bar;
- at an ambient temperature of 20 ° C to 20 bar;
- are destroyed at 80-90 bar.
One of the key parameters that determine the durability of the system is the operating pressure. Usually, in domestic heating systems, it does not exceed 4 Bar, and in individual systems it generally lies within 1-1.5 Bar. So, according to this characteristic, MP pipes have a significant margin for use in heating systems.
Diameter of metal-plastic pipes for heating
When designing a heating system, the diameter of the outlet pipes from the boiler is taken as a reference point. Further, even if the system is polymeric or metal-plastic, metal pipes of the same diameter go at least half a meter. You can already connect plastic ones to them. Moreover, it must be taken into account that the diameter is considered according to the internal lumen, and not according to the external one. Since the wall thickness of metal pipes and metal-plastic pipes is different, the outer diameters will not match exactly.
In general, if the system is large, it is better to order a heat engineering calculation from a good specialist, and decide only on the type of pipe that you prefer to do the wiring. Moreover, the choice of a specialist is very important: far from everyone can do a heat engineering calculation, and a fairly common situation is when a “specialist” simply takes someone’s finished project, changes something, and sells it as his own (for a lot of money). So be careful.
If the length and number of devices is small, you can choose the diameter of the pipes for heating yourself, adhering to the rules. In general, the rules for choosing the diameter of pipes look like this: before the first branch, the diameter is the same as at the inlet / outlet of the boiler, and then there may already be options. Each branch has a smaller diameter by one step. For example, a 24mm pipe came out of the boiler. Next comes the division into two branches, which will already be performed by 18mm pipes. From the branch to the device or group of devices, a 12mm branch departs.
The "return" is assembled in the same way, only in the reverse order: from smallest to largest.
The installation of metal-plastic is good because in some cases you can do without special tools. But this is when assembling the cold water circuit, in extreme cases, for hot water supply. But for the installation of heating, so that it was assembled for a long time, it is difficult to do without skills and special equipment.
Let's start with the types of fittings. There are three types of them for MP: pressed, compression (Vestol type), and collet connection - fittings with a split ring. In fact, they differ in the degree of "separability": collet - collapsible, compression - conditionally collapsible and press fittings - non-collapsible.
Split fittings
Any connection based on these parts can be assembled / disassembled repeatedly. This group of fittings has three names: detachable (collapsible), collet and threaded. Their prices are higher than similar fittings of other groups. Their body is made of brass, and the assembly is fixed on the pipe with a gasket and a ferrule. The assembly procedure is as follows: a nut is put on a calibrated pipe section (a special device is used that restores the ideal shape and size after using scissors), then a ring, after which the fitting body is pushed all the way. A ring is put on it, on top - a nut, which is tightened by hand, and then with a key.
Such connections are good for distributing cold water, with some caution they can be used for hot water (provided that the fittings will not be walled up). They are not recommended for use in underfloor heating systems, although the floors assembled at the “company” have been working for 12 years without problems, but there was 100% confidence in the authenticity of the products. In heating circuits, such elements stand without problems for several years (2-3 years), then they begin to leak. They can be tightened several times, but when the thread reserve has already been exhausted, they have to be changed.
But in some places a detachable connection is necessary. How to install them on MP pipes is shown in the following video.
Compression fittings
Compression or compression fittings are conditionally collapsible. They consist of a fitting and a union nut, which are fixed on the pipe with a ferrule. These nodes are also installed without the use of any special devices; two keys will be needed (one may be adjustable). Their scope is the same as for detachable ones: mainly for cold water, maybe for hot water.
Press fittings
The best connections for today for heating are press nodes. Most installers agree with this. Only such fittings provide a reliable connection that "holds" both temperature and pressure. They are non-separable, they can be "monolithic" into the floor or wall (if done correctly). But without special equipment - press machines are indispensable here. They are expensive - from $ 1000, but you can rent it for a very reasonable price - $ 30-50 / day.
The process of mounting a press fitting and crimping units is shown in the video, where it is carried out by a specialist from Valtec, one of the market leaders.
How to bend a pipe
In some places, it is required to make a bypass or a bend in the pipe. How to bend an MP pipe with your hands, without the use of special tools and with them (with an internal and external spring) is described in the video below.
How not to buy a fake
The quality of metal-plastic pipes for heating is very important: good quality MP systems last for decades, while fakes start to drip after 2-3 years, and if the pipe diverges along the metal seam, then pour. Even if this does not happen, then after 7-8 years aluminum is destroyed, and problems still begin. Therefore, pay maximum attention to quality. How to distinguish quality pipes?
First, buy from a specialized outlet and ask for a certificate. This, of course, is not a guarantee, but the complete absence of papers is an exact sign of counterfeit products: official suppliers provide each batch with the relevant documents.
Second, look closely at the pipes/fittings. If you have previously chosen a manufacturer, find information about how everything should look like: the color of the outer plastic layer, the color of the inner plastic, texture (smooth, rough), diameters and brands of manufactured products, marking details and brand writing. Often this is how, by external signs, a fake can be determined: normal firms put inscriptions clearly, in full accordance with the spelling. On fakes, the inscriptions are blurry, often uneven, letters or signs are inscribed / omitted in the brand names. This is done mostly on purpose: after all, if the logo matches completely, the campaign can sue. And so, a similar name, but different ...
Thirdly, pay attention to the pipe cut. Most major manufacturers butt weld aluminum. The presence of a seam "overlap" is a sign of low quality. Also pay attention to the thickness of aluminum - it should be the same. As for the thickness of the polymer layer, the inner one must be unambiguously of the same thickness, and the surface inside the pipe should be even and smooth. The outer layer, if the pipe is of a traditional shape, must also have the same thickness. An exception is pipes of a special (not round) shape. Then it is also desirable to know in advance the parameters of the outer layer of the polymer. Here, actually, and all means.
findings
General conclusions can be drawn as follows: when using high-quality materials and having “straight” hands, metal-plastic pipes for heating can be used. Moreover, even with their shortcomings, they behave better than steel in heating systems. But this is true only for high-quality "branded" materials and for systems in which the coolant does not warm up above 95 ° C. With centralized heating, such temperatures simply cannot be, therefore metal-plastic can be safely used. With individual heating with boilers on automatic control, there can be no problems: they can set the temperature of the coolant. And if so, then set 85-90 ° C and reinforced polypropylene (PP or PP) and metal-plastic (MP) will feel great.
It will be more difficult with plastic pipes in systems with solid fuel boilers: if overheating protection is not installed, then the coolant can be above 95 ° C. Some super-quality MP and PP pipes tolerate infrequent exceeding of the limit. But it is precisely "tolerate" and "infrequent". To equalize the temperature in the system with a solid fuel boiler, heat accumulators must be installed. They take on the "surplus" heat in the maximum combustion mode, and then give off the accumulated heat when the boiler is extinguished. With such a device, and in this case, you can put plastic.
The old metal pipelines in heat supply systems are being replaced by products made of more practical and convenient materials. The most popular today are metal-plastic, polyethylene and polypropylene pipes with brass and bronze connecting elements.
Metal-plastic pipes for heating are characterized by excellent hygienic, hydraulic and thermal qualities. They do an excellent job with the functions of heating and water supply.
Combination of metal and plastic
The metal-plastic wall is made of an aluminum base coated with high-density polyethylene. A special adhesive layer is applied to it using the extrusion method from the inside and outside. With the help of the outer layer of polyethylene, the product is protected from atmospheric corrosion and mechanical damage.
Aluminum
The middle aluminum layer gives the pipe mechanical and hydraulic strength, making it oxygen-tight. The thermal deformability of polyethylene is reduced by more than 7 times due to the presence of aluminum.
The edges of the aluminum base can be joined by laser butt welding or ultrasonic overlap welding. Laser welding gives a more durable option.
Polyethylene
The inner layer consists of heat-resistant polyethylene. It forms a smooth surface and corrosion protection of the metal. Polyethylene, which is used in production, does not contain harmful chemicals. This suggests that metal-plastic pipelines are suitable for drinking water supply. Polyethylene prevents the processes of reproduction and spread of microorganisms in the water.
To provide thermal insulation and reduce heat losses, pipelines with closed pores and concentric insulation are used.
Characteristics and properties
Metal-plastic pipes bend and cut without much effort. They are transported and stored in bays. Pieces of the desired length are cut from the bay. Due to the low weight density of plastic and aluminum, a low weight of the finished product is ensured. It also makes it easier to transport.
Such pipes have a fairly long service life. In practice, it exceeds the periods between planned overhauls of premises. If water freezes in a metal-plastic pipe, then an accident will not occur. The pipe will swell locally and retain its performance.
The flexibility of this type of pipes allows them to be used for underfloor heating.
Before proceeding with the installation of the heating system, you need to determine which pipelines are best suited for a particular room. To do this, you need to take into account not only the technical characteristics, but also the positive and negative sides of the selected material.
Main advantages
- reliability and durability;
- pronounced resistance to salt deposition, aggressive environments;
- resistance to silting and overgrowing;
- high throughput;
- low weight and high plasticity;
- easy to mount with your own hands;
- good maintainability;
- high coefficient of noise-absorbing ability;
- low thermal conductivity.
Negative sides
- it is forbidden to use in fire safety systems;
- can not be installed near heat sources, the temperature of which is more than 1500 ° C;
- unreliability of fittings;
- high sensitivity to defrosting.
It is not recommended to use metal-plastic products outdoors. They can burst if you start to defrost the heating system. As a result, there will be an emergency shutdown of the boiler from electricity, which leads to the replacement of all pipes and the dismantling of the system.
Considering all the characteristic features, it can be noted that the use of metal-plastic pipes for heating residential facilities is most justified.
Types and features
Knowing the structure of the product and its labeling will help determine which pipelines are best suited for a private house and apartment.
The most popular metal for the production of elements of any diameter is aluminum, but polymers differ significantly. Any metal-plastic pipe used for heating must withstand a temperature of 95 ° C and pressure up to 7 atmospheres well.
Unlike hot water supply, heating involves the transfer of a coolant at a higher temperature and at a lower speed, which causes increased pressure on the pipe walls. Such conditions can lead to rapid aging of the polymer, which will significantly reduce the service life of the product.
That is why for heating it is better to choose pipelines with piping made of cross-linked or heat-resistant polyethylene. Cross-linking and three-dimensional structure increases strength and resistance to temperature deformations. Such pipes are marked with the letter designation PE-X and PE-RT.
Polypropylene (PP-R) and ordinary polyethylene (PE-R) are well suited for cold water applications.
Given the presence of a metal core and a polymer shell, the service life of such a product is highly dependent on the properties of these materials.
Heating system installation
Do-it-yourself installation and wiring of metal-plastic pipes does not require much effort and special tools. But still, it is worth immediately preparing a device for calibration, an adjustable wrench and a knife.
Due to the high elasticity of polymer and aluminum, it is easy to bend the pipe with improvised means, but if desired, you can use a special tool.
fastener requirements
After drawing up a plan for the location of pipelines, their installation can proceed in any convenient sequence. Pipe fittings should be located no further than 50 cm apart, otherwise sagging and flow disturbances may occur during operation.
Improving Efficiency
To reduce heat loss and protect against freezing, each pipe section can be placed in a corrugation that retains heat. As a result, the heating efficiency increases by 10 - 20%. But it is not worth mounting part of the system on the street, because the material may not withstand significant temperature changes.
Connection of elements
The pipeline system is connected through special brass or metal fittings. They easily form the necessary articulation. The simplest installation is the one where threaded compression fittings are used. Fastening and sealing is carried out with a nut together with a ferrule on the outside and compression rings on the inside.
Diameter selection for heating device
Most often among the proposals you can find pipes made of metal-plastic, for which the outer diameter varies from 16 to 63 millimeters. The wall thickness can vary from 2 to 3.5 mm. Which pipes are better to use depends on the maximum pressure.
When marking, two values \u200b\u200bare often used - the outer diameter with an indication of the wall thickness or the inner diameter.
If we consider the main options for execution, then all pipelines for a private house can be divided into several groups:
- an outer diameter of 16 and 20 mm is most often used as a outlet when supplying hot water to faucets in the bathroom and in the kitchen;
- a section of 26 and 32 mm along the outer circumference of the pipe can be used for installing a “warm” floor system and organizing heating wiring when working with low pressure flows;
- an outer diameter of 40 and 50 mm is perfect for creating the basis for individual water supply and heating systems in a private house.