Heating soldering scheme in a private house. Features of working with polypropylene. Heating from polypropylene pipes - collector scheme
When installing a heating system, it is necessary to select the material for pipeline heating lines. Today, the installation of heating from polypropylene pipes, pipelines made of copper and metal-plastic.
Ferrous metal pipes are also still in use, but their use is steadily declining.
The photo below shows the main elements of polypropylene pipelines:
- pipes;
- fitting;
- tees;
- bends;
- couplings.
Production of pipes from polypropylene
The raw material for the production of polypropylene pipes is a thermoplastic propylene polymer. Polypropylene pipes are made by extrusion from this material.
This makes it possible to achieve good weldability of these elements. Shut-off valves and fittings made of polypropylene are made by injection molding.
For the production of all these elements, relevant international and national standards have been developed. The color range in which polypropylene pipes and fittings are produced is quite wide (from white to red).
Detailed color solutions can be found in the special catalogs of manufacturers.
When designing a new house or dwelling, it is very important to choose the right heating system from polypropylene pipes, since the consumption of electricity or fuel during subsequent operation depends on it, as well as appearance premises. Installation of heating from polypropylene pipes is carried out according to three types of schemes:
- single pipe;
- collector.
The heating system used in these installation schemes can be with forced movement of water or antifreeze and gravity. With vertical mounting and horizontal.
Pros and cons of single pipe wiring
A single-pipe system is a type of connection in which liquids, moving from one radiator to the next, lose temperature. With this scheme, there is no movement of the fluid in the opposite direction. It is mainly mounted vertically, but sometimes a horizontal one is used. It is used for heating equipment in multi-storey and private houses. The radiators can be connected from above or below.
Cons of this layout
- the inability to regulate the heating temperature in different parts of the wiring. It is generally difficult to regulate it, since a decrease in temperature regime at the beginning of the wiring will result in a minimum temperature at the end;
- if the temperature difference between the top point of the wiring and the bottom of the riser is large, then at the bottom it may be necessary to install heating batteries with a larger number of sections and area than at the beginning of the riser.
- strong pumps are needed for normal operation, heating costs for boilers increase, operational wear increases, there is a need for frequent replenishment with water.
Advantages of single-pipe heating distribution with polypropylene pipes
- gives great savings when laying in consumables and labor hours;
- more acceptable appearance (less pipes are laid);
- today there are many possibilities to correct the functional shortcomings of this system with the help of radiator regulators, thermostatic sensors.
The difference between two-pipe wiring
With a two-pipe heating distribution, a heat agent (water, antifreeze, steam, gas) with the same heating temperature is evenly distributed throughout the equipment. Radiators are connected both from above and from below at the same time. From the common riser, a hot heat agent enters each radiator through the top connection, circulates in heating battery and goes through the lower connection through a common return line to the boiler for a new warm-up. The advantage of such a system is that with the help of a thermostatic head or a servo drive, the temperature of any radiator can be adjusted separately, and this will not affect the rest of the heating system. With this installation, the application is larger than DN 20x3.4. as well as a radiator valve over 1.2 does not make sense, it will not get warmer. The length of the polypropylene pipe supplying the heat agent should be no more than 25 meters.
The disadvantage of the scheme is the high cost of laying the return pipe system.
Heating from polypropylene pipes - collector scheme
Such a system is different in that each radiator is connected directly to the collector. Radiators are connected from two sides. On one line, the heat agent supplies heat to the heating battery, on the other hand, the cooled agent returns to the collector. With this scheme, polypropylene pipes, as a rule, are carried out in a straight line and laid inside the screed. Their length is quite large. But it is easier to manage this system, the heat will spread evenly. With the help of a hydraulic arrow, it is possible to draw circuits with different temperatures and pressure drops. The collector scheme is not suitable for multi-storey buildings.
Disadvantages of the collector circuit
- high pipe consumption, compared with single-pipe wiring;
- complication of work, since there should be no connections;
- the heating system is only forced;
- installation of the same number of pumps as autonomous circuits, distributed throughout the premises.
Polypropylene pipes are not afraid of defrosting. But it must be borne in mind that defrosting can damage the boiler and expansion tanks. Soldering polypropylene pipes requires a special tool. The nodes are soldered separately, and in finished form they are installed in the place where they will stand.
You also need to know that when connecting, you need to choose pipes that meet the following correspondences:
After weighing all the pros and cons, it is worth choosing a scheme that is most suitable for specific conditions.
Selecting a heat source
Heating a private house depends on the chosen heat source:
- If gas is supplied, it is necessary to purchase a wall gas boiler with automatic control, pumps and protection system. In the absence of a chimney, the boiler must be equipped with a combustion chamber closed type and a coaxial pipe that will bring air to it and remove exhaust gases. The exit of the coaxial pipe can be organized through the wall of the house, which saves on the construction of a chimney.
- If the house is heated electric boiler, best solution will be the purchase of an automated boiler with a pump, an expansion tank and a security group. Such a heating system made of polypropylene pipes can be installed independently, as it allows you to avoid many errors during installation and selection of materials.
- If the heat generator in your house - solid fuel boiler, then its installation is possible only by specialists or if you have experience in welding heating pipes. Bringing polypropylene pipes to solid fuel boiler it is possible, but for this it is necessary to professionally develop a boiler piping scheme, because at the outlet the temperature of the heated water reaches 100 0 C.
Development of a heating scheme
Do-it-yourself heating with polypropylene pipes begins with the development of a heating scheme. Connecting pipes to radiators can be done in different ways:
- one-pipe scheme- the most simple circuit, in it each radiator following from the boiler is always with a lower temperature than the previous one. This method saves material consumption, but with it the heat is distributed unevenly, so the single-pipe scheme is inefficient, you should not give preference to it;
- collector circuit– the length of the pipes is much longer, but the operation and regulation of work heating system it is simplified, moreover, heat will be distributed throughout the house fairly evenly;
- two-pipe scheme- the most optimal option for heating a private house, in this case, pipes are laid in the walls or floor of the building around its entire perimeter. The figure below shows an example of a two-pipe heating method suitable for a house up to 100 m 2 in area.
If the system has a built-in expansion tank of a suitable volume, a pump and a safety group, positions 4, 5, 6, 7 are not needed.
Pro tip:
No shut-off and control valves may be installed in the area between the boiler and the safety group.
Choosing the diameter of PP pipes for heating
When connecting metal-plastic pipes with polypropylene pipes, it must be taken into account that the diameters of polypropylene pipes for heating correspond to the following parameters of metal pipes:
- polypropylene pipes for heating Dn 25x4.2 are connected to metal-plastic pipes 20x2;
- to pipes 16x2 there is a pipe made of polypropylene Dn 20x3.4
- With metal pipe 26x3 connects polypropylene Dn32x5.4.
If heating pipes are connected to radiators from main pipeline, then with a two-pipe scheme, a polypropylene pipe 20x3.4 is used. The use of pipes with a large diameter, as well as radiator valves of more than 1.2”, is not practical. The statement that the larger the diameter of the pipe and thermostatic valve, the warmer it is in the house is false.
For productive operation of the heating system, the length of the supply pipeline from the boiler to the very last radiator should not exceed 25 m, and the power should be a maximum of 12 kW. In other words, the correct and efficient operation of a heating system with 20x3.4 pipes is possible when 6 radiators are connected, each of which consists of 10 sections. If more radiators are connected, it will be necessary to increase the length of the pipes for their connection, and this will lead to uneven heating of the radiators furthest from the boiler.
But if connecting more radiators or increasing the length of the pipes is a necessity, you can use polypropylene pipes with a large cross section, for example, 32x5.4, then metal-plastic pipes with parameters 26x3 are suitable for them. Or use another way - spend two heating circuits, not just one.
Features of working with polypropylene
Working with polypropylene pipes requires the presence of a special soldering tool designed for joining polymeric materials. Soldering is best done by two people. At the same time, overheating of the ends of the elements to be connected is not allowed, and the fixation of pipes and fittings for the first 10 seconds after connection must be rigid. Polypropylene pipes are not afraid of defrosting the heating system, but in addition to them, the system includes a boiler and expansion tanks that will fail if defrosted.
Pro tip:
If you have never soldered polypropylene, it will not be superfluous to read the instructions. It is also possible to carry out training soldering before starting the installation of the heating system. To do this, it is enough to buy inexpensive ordinary pipes with simple couplings.