How to choose polypropylene pipes for water supply? Which pipes are best to choose for water supply to an apartment? PP pipes for hot water supply

Progress requires excellence in every branch of production. According to this principle, consumer demand has moved from metal pipelines to products made from polymer elements. Polypropylene pipes for water are used as alternative option distribution of hot and cold water supply networks with minimum quantity shortcomings. Today, this type of pipe is used for laying central main water networks and installing intra-apartment wiring.

A water pipe made of polypropylene has a set of fundamental advantages, which we will get acquainted with during the article.

Construction companies constantly use polypropylene pipes for hot water supply to create new generation communication and utility networks. This is due to the fact that the installation procedure for such a water supply system occurs when minimum costs and in a short period of time. Let's find out whether it is safe to use polypropylene pipes for hot water, and which ones are better to choose?

Properties and physical characteristics of polypropylene: how temperature affects PP pipes and other points

Target market segment poly propylene pipes pipelines for hot water supply are represented by products with a maximum permissible temperature of 950 C, which is sufficient for operation in apartment conditions with centralized heating, and even more so in autonomous heating systems Oh. Not every manufacturer produces more temperature-resistant polypropylene.

Economic. The note marked on the product with a stripe along the pipe states that the maximum permissible temperature– 95 degrees, although polypropylene for hot water must withstand higher temperatures. This is done in order to artificially lower temperature limit. Let's imagine that the temperature on the pipe is 100 degrees. Consequently, if the material does not meet quality standards, then when water is heated to 98 degrees, the polypropylene will deform, and the consumer will file a lawsuit for non-compliance with the declared characteristics. Litigation will end in favor of the consumer, and the manufacturer will have to pay a fine. Note that hot water supply pipelines made of polypropylene are used in the construction and repair of large companies, therefore, the cost of damage becomes fabulous.
Technological. During production polypropylene products There are batches with defects. Track the shipment of material with varying physical and chemical composition- the process is labor-intensive. Therefore, it is preferable for the manufacturer to indicate a lower limit of operating temperature and pressure, so that this does not later lead to the first reason.

Technical characteristics: advantages of PP pipeline for cold and hot water

For apartments and private houses, the temperature of the hot water circuit and the heating rate does not exceed 80 degrees

The human factor is eliminated when an incompetent mechanic supplies hot water not in accordance with necessary standards. Let's move on to the advantageous features of polypropylene water pipes:

Each manufacturer indicates an individual service life of PP pipes for hot water. But in any case, this figure varies within 50 years, which is twice the service life of black steel pipelines.
The smoothness of the inner walls of the product quickly conveys operating temperature and pressure throughout the structure. For the same reason, the possible accumulation of growths inside the pipe is eliminated.

In conditions of increased water hardness in some regions, polypropylene successfully copes with limestone deposits, and therefore the diameter of the internal section of the pipe does not change for decades.

excellent resistance to corrosion.
for hot water will not create problems for the consumer, since in the reverse process the walls can withstand pressure and do not burst (applies to reinforced products).
Pipes for hot water supply and heating made of polypropylene have high performance heat capacity and low thermal conductivity. These properties will save on the consumption of fuel used to heat water.
For installation polypropylene structures a soldering machine is used for sleeve welding, therefore, the installation of PP pipes is often done independently.

Installation of a polypropylene water supply section is several times faster than that of steel pipes.

When making hot pipelines from polypropylene, environmentally friendly compounds are used that do not harm human health.

Reinforcement of polypropylene water pipes of any diameter with fiberglass

PP pipes for hot water are reinforced with special compounds that save the product from mechanical deformation during operation. According to the laws of the market, the following classification of polypropylene pipelines for hot water is distinguished:

With metal braid.
With fiberglass.

In the first case, the pipe is reinforced using aluminum foil, which covers the product along the entire outer diameter. Such pipelines require additional cleaning of the outer layer for heating in sleeve welding, which causes additional problems during installation. This is especially felt in the absence of special tools. Another disadvantage of polypropylene with metal braid is that such products often swell due to the use of low-quality materials in production. However, such mechanical modifications are not covered by the manufacturer's warranty.

The second type of pipes with fiberglass is free of the above problems and has a number of additional advantages: they do not delaminate, are not subject to electrochemical attack, cope better with expansion when heated, etc. They are used to install cold and hot water pipes in an apartment or private house. Such products are used when laying centralized systems heating and hot water supply.

WATCH THE VIDEO

Polypropylene pipes for hot water have entered the communications laying market well.

Polymer products are an excellent alternative steel pipes. This point is also relevant for products made from Random Copolymer polypropylene, which are used for the installation of both cold and hot water supplies. Thanks to such products, you don’t have to worry about the integrity of the pipeline during its operation over a long period.

In this article we will talk about how to choose polypropylene pipes for hot (DHW) and cold (CW) water supply.

Polypropylene products owe their remarkable characteristics to various additives (for example, inhibitors and plasticizers). According to experts, four types of products are made from this material. Polypropylene water pipes are marked with in Latin letters PP (from English - polypropylene).

All products of this type are distinguished in a similar way. In the subsequent combination, polypropylene additives are encrypted. The final choice of pipes should be based on a correct understanding of the letter meaning, as well as their properties:

PPB. This type is a combination of two materials: polyethylene and polypropylene, with the first accounting for 30% of the total mass. PPV is highly flexible and resistant to various temperature conditions. An excellent option for using pipes with this marking is the installation of heated floors.
P.P.H.. This combination is the designation of a homopolymer of polypropylene, which has the appearance of hard plastic. This material is exposed high temperatures. This property allows PPH to be used in the manufacture of pipes for cold water supply. Such products are mainly used for arranging ventilation and air conditioning systems.
PPR (PPCR). An integral part The molecular chain of this type of polypropylene is ethylene molecules. Thanks to this composition, the load is distributed evenly over the entire thickness of the wall, which guarantees a long period of operation in the water supply system in both hot and cold versions. Possesses PPR and resistance to pressure drops.
P.P.S.. The abbreviation of such a material indicates that it has excellent user characteristics and a fairly high threshold of heat resistance. The search for a polypropylene pipe for hot water supply can be stopped at such a PPS product, and the reasonable price-quality ratio only improves the properties of the product.

It should be noted that using the same material for different purposes is not always possible.

In situations where the expected temperature of the filled liquid is above 70˚C, the use of PPR pipes is strictly prohibited. This is stated in the recommendations of the manufacturer of these products.

Maximum permissible temperature and marking of polypropylene pipes

Availability symbols on products made of similar material allows you to learn about their parameters and choose the best option for the pipeline. Let's consider all types of markings:

PN10. This type of product, having an outer diameter of 20-110 mm and a wall thickness of 1.9-10 mm, can withstand a pressure of 1 MPa. These products are most often used for transportation cold water(20 °C and below) and installation of a heated floor system (less than 45 °C).
PN16. Pipes of this type can withstand a maximum pressure of 1.6 MPa. The products have a diameter of 16-110 mm and walls with a thickness of 2.3-15.1 mm. This brand is rarely used. Areas of application of the products are heating communications under the layer flooring, as well as water supplies with temperatures below 60 °C.
PN20. Pipes with this grade can withstand pressures of 2 MPa and temperatures up to 80 °C. The diameter of the products varies between 16-110 mm, and the wall thickness is 1.6-18.4 mm.
PN25. Such products take the form of specialized pipes used in heating with reinforcement. It can withstand pressure of 2.5 MPa and temperature of 95 °C. Such technical specifications allow them to be used for the installation of hot water supply systems and process pipeline systems. The diameter of the products varies from 21.2-77.9 mm, and the wall thickness is 4-13.3 mm.

The table below shows the dependence of the service life of polypropylene products on water temperature and maximum permissible pressure.

Polypropylene pipes with reinforcement

Cylindrical products with reinforcement can significantly simplify the arrangement of a hot water supply system, which is explained by their extreme elongation with increasing temperature. This property may cause depressurization of the complex of structures.

This situation can be prevented by careful pipe routing. When carrying out such activities, the volume of labor costs and, consequently, the cost of equipped hot water supply will increase several times. This drawback can be eliminated by choosing reinforced polypropylene products.

In this case, reinforcing polypropylene pipes used for hot water supply will help achieve the required technical indicators.

Among the reinforcement methods, the following are noted:

Using an additional polyethylene layer to line the interior space.
The use of foil, which is placed between the walls of a polypropylene pipe for hot water supply.
Using fiberglass, layers of polypropylene connected to this material are sintered and form a solid monolithic structure.

The use of such technologies can prolong the life of pipes, increase their strength characteristics and eliminate internal rusting.

The first method has gained the most popularity, the installation of which is quite simple. Products obtained in this way are very easy to solder. This explains the fact of their increased demand in the hot water supply system, which is facilitated by fiberglass reinforcement, as well as their use in places that involve repeated cutting and joining of water supply sections.

Experts say that the best option is a water supply system equipped with elements with various technical indicators. It is this that shows the high efficiency of operation of the structure with a maximum period of its service.

The scope of use is limited by the excellent elastic properties of such products, which, along with increased ductility, significantly reduces the range of diameters that manufacturers can produce. Thus, the maximum diameter of polypropylene pipes reinforced with glass fiber is 63 mm.

The combination of these factors often leads to the fact that experts prefer to choose polypropylene pipes with aluminum reinforcement for both hot and cold water supply systems.

The expediency of this choice is explained by the high rigidity indicators similar products, which means a prolonged service life, as well as the presence of pipes with diameters that are 2 times larger than products reinforced with fiberglass.

Selection of pipes by diameter

Polypropylene products for water supply in private houses or apartments have a number of characteristics that are taken into account when purchasing them:

a pipeline with a length of less than 10 m requires the use of pipes with a diameter of 20 mm;
engineering structures, the length of which is within 10-20 m, must be equipped with products with a diameter of 25 mm;
pipelines with a total length exceeding 30 m require products with a diameter of 32 mm.

When installing risers, a polypropylene pipe with a diameter of more than 32 mm is used.

A wide range of fittings and models with different diameters increase the popularity of polypropylene products.

Sound absorption

Excellent sound absorption is another reason for purchasing such products, which is simply irreplaceable in cases of transporting water or coolant. Polypropylene is not afraid of temperature fluctuations and pressure changes. Due to their low thermal conductivity, the pipes are characterized by the absence of condensation. The positive aspects of polypropylene products for cold water supply systems include their low weight, which greatly facilitates their transportation and loading and unloading.

To implement installation work requires the participation of two craftsmen and the use of a special soldering iron. Attraction additional equipment inappropriate. The installation of a water supply system equipped with polypropylene cylindrical products proceeds much faster than the installation of a similar structure with metal pipes.

Positive characteristics

One of the main advantages of such products is their long service life. You can help prolong it by doing right choice water pipes taking into account the manufacturer's recommendations. The rational installation of reinforced products exclusively in areas of high load can reduce the cost of setting up the system.

The approximate service life, which is indicated by manufacturers, is about 50 years, while the installation of pipes in a cold water supply system increases this period to 100 years.

This design can withstand short-term increases in pressure or temperature. Among other advantages that products of this type have, the following are noted:

resistance to mechanical stress and aggressive substances;
maintaining all standards of sanitary hygiene of the internal walls of products in contact with drinking water;
increased sound insulation;
absence of condensation, which is ensured due to low thermal conductivity;
ability to maintain integrity during freezing and thawing;
innovative welding technologies, which allow high-quality connection of system elements;
the ability to maintain the internal diameter even with a long service life due to the absence of corrosive deposits;
light weight, which facilitates transportation and installation processes;
uniform color of the product, which eliminates staining.

Famous manufacturers

The pricing policy pursued by manufacturers of polypropylene pipes for water supply is important nowadays:

Affordable prices distinguish Chinese products, but when choosing, you need to carefully read the manufacturer. These have proven themselves well famous brands, like BLUE OCEAN and Dizayn.
Domestic brands such as Pro-Aqua, Politek, RVK, Santrade and Heisskraft are quite worthy of attention.
The middle price category includes products from Turkey (for example, Pilsa, TEBO, Vesbo, Kalde). It should be noted that they are slightly inferior in quality to manufacturers from Europe.

The most expensive products are from the following manufacturers:

Aquatherm, Banninger, Rehau and Wefatherm (Germany);
FV-Plast and Ekoplastik (Czech Republic).

The high cost of polypropylene products is the main negative point when purchasing them.

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Metal water pipelines are gradually being forced out of the market. They are being replaced by polypropylene pipes for cold and hot water supply, the service life of which is much longer, as the manufacturers themselves assure. The editors of the site dealt in detail with the issue of choosing products for water supply and determined by what parameters it is best to choose them and how to professionally connect them.

Available on the market wide choice polypropylene products

Polypropylene pipes for cold and hot water supply: scope of application

Today, polypropylene pipes are very common in various areas:

The opinion that any polypropylene pipe is suitable for water supply is erroneous. Manufacturers produce several types of products, each of them has its own role. Polypropylene products are designated by the letters “PP”.

When constructing new water pipelines, you can immediately give preference to this product rather than choosing between polypropylene and metal. The products are also widely used when it is necessary to replace an outdated water supply system. The most common application is for intra-house and intra-apartment networks.

Advantages and disadvantages of polypropylene pipes

It should be noted that products of this type have many advantages. That is why she gained popularity so quickly. Main advantages:

corrosion resistance;
resistance to acids and biologically active substances;
lack of reaction allows you to get the output clean water without impurities, iron content, retaining its color and taste;
the water pressure is stable, since the hydraulic resistance inside the product is small;
installation is very simple, in addition, you can easily create a system of any complexity;
the material is not afraid of high and low temperatures;
low cost;
a reduced level of thermal conductivity avoids heat loss.

Speaking about the material, one cannot fail to note its shortcomings. These include:

the need to carefully select products for a specific pipeline, otherwise the material will become unusable very quickly, and ruptures are possible;
market presence large quantity cheap low-quality products;
the need to have a special device for processing joints and be able to work with it.

There are practically no disadvantages to this type of product. Serious problems are not related to the pipes themselves, but to defects in their production.

Types of polypropylene pipes

It is important to understand that for hot water you need to choose one type of product, and for cold water - another. Selecting products of the same type is a common mistake, which often causes a system breakdown.

Products are distinguished:

according to the material of manufacture;
by type of reinforcement.

In order to choose the right material, let’s get acquainted with the nuances of its production.

According to the material of manufacture

When purchasing pipes for your own needs, you will definitely pay attention to the markings. These signs and letters speak volumes. First of all, about the material of manufacture. There are several types of products:

Random copolymer, labeled as PP-R. Made from polypropylene copolymer and designed for hot water supply.
Homopolypropylene, marked as PP-H. They can withstand high operating pressure and are therefore widely used in industry. Suitable for cold water supply.
Block copolymer, PP-B marking. Used for underfloor heating systems and cold water pipes.

Important! If the pipeline is external, it is better to pay attention to the presence of an ultraviolet-resistant shell, which will allow the pipes to last an order of magnitude longer.

The table below shows the safety factor for different types of products:

As you can see, PP-H pipes are highly dependent on the water heating temperature.

Related article:

Plastic pipes for water supply. In the publication we will consider the sizes and prices, types, advantages and disadvantages of plastic pipes, selection criteria, as well as the nuances of self-installation and recommendations from specialists.

By type of reinforcement

Reinforcement is an indicator that affects the coefficient of thermal expansion, reducing it. This is done in one of several ways:

using fiberglass (marked with the letters FB);
aluminum foil when placing it closer to the inner edge of the pipe (marking AL);
aluminum foil when placing the layer closer to the outer edge (AL marking);
using a composite (marked GF).

If the aluminum layer is located closer to the top edge, you will need to clean the edges before work. Elements reinforced with fiberglass or composite are considered to be of the highest quality.

Main technical characteristics of polypropylene water pipes

Let's talk about the main characteristics of pipes, according to which the buyer makes a choice in the store:

diameter of polypropylene pipes. Products with a diameter of 15 to 1200 mm are produced, which are designed to provide water to both private and apartment buildings;
PN marking will allow you to select a product for both cold and hot water, as well as for a certain water pressure (the table is shown below);
internal diameter or wall thickness. The thicker the wall, the more pressure it can withstand water;
length. This parameter has no qualitative significance, however, let us clarify that all factory products have a length of 6 meters.

Technical requirements for polypropylene pipes for water supply according to GOST

Expert's point of view

Kirill Mikhailov

Head of the group "Water supply and sanitation" LLC "GRAST"

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“In our country, GOST R 52134-2003 applies to polypropylene pipes for water supply, which determines the quality standard.”

This quality standard is the only one to characterize the quality of both pipes and fittings and connecting elements. General requirements for water supply polypropylene pipes are as follows:

they must have a round cross-section;
must be pressure;
used in residential and non-residential buildings, as well as in industries;
serve for both technical and drinking water.

Marking of polypropylene pipes for water supply

Marking of polymer pipes for water supply allows the buyer to quickly determine whether this product is suitable for him or not:

PN-10 intended for cold water and the construction of “warm floors” (up to a temperature of +45°C);
PN-16 suitable for installing “warm floors” or hot water, the brand is unpopular with craftsmen;
PN-20 designed for hot water supply with a maximum temperature of up to +80°C;
PN-25 the most durable, they can withstand water temperatures of +95°C.

Important! Hot water products must withstand high temperatures.

The table below includes the main characteristics of pipes. The marking is present directly on the product.

Table of main characteristics of pipes

Marking	Allowable pressure, MPa	Outer diameter, mm	Wall thickness, mm	Permissible water temperature, °C
PN-10	1	20-110	1,9-10	45
PN-16	1,6	16-110	2,3-15,1	60
PN-20	2	16-110	1,6-18,4	80
PN-25	2,5	21,2-77,9	4-13,3	95

Table of standard sizes of polypropylene pipes

We invite you to familiarize yourself with the table standard sizes PP products. Presented as an option with a reinforced product, and with a non-reinforced one.

Standard Size Chart

Diameter, mm	Quantity per package, m	Diameter, mm	Quantity per package, m
20	100	20	100
25	80	25	80
32	40	32	40
40	32	40	32
50	20	50	20
63	16	63	16
75	12	75	12
90	8	90	8
110	4	110	4

How to choose the diameter of polypropylene pipes for water supply

In everyday life, water pipes from 20 to 32 mm are considered the most used. The diameter depends on the length of the water pipe as follows:

more than 30 meters - Ø32 mm;
from 10 to 30 meters - Ø25 mm;
up to 10 meters - Ø20 mm.

The diameter of PP pipes is also selected based on the following conditions:

pressure magnitude;
length of the water supply system;
number of connections and turns;
number of users.

If the design is complex, you will need to increase the diameter of the pipe. The same law also works with a significant increase in consumers.

Which polypropylene pipes are better for water supply?

The plumbing system is divided into two types:

cold water supply;
hot water supply.

Very often in private houses only cold water is supplied, which is also supplied to the boiler, and then hot water is distributed through a separate branch to the baths. The use is unjustified, since their service life is not so long. In addition, water reacts with the material, rust is formed and reduced.

Polypropylene pipes for hot water

Plastic pipes for hot water must withstand high blood pressure and not deform when heated.

Important! Polypropylene softens at a temperature of +140°C.

The manufacturer always indicates that the maximum permissible water temperature inside the system can reach +95°C.

For hot water supply, it is better to use a reinforced pipe, because it is protected from expansion and has a longer service life. The highest quality reinforcement occurs using fiberglass or composite. The most suitable product for hot water is marked PN-20 or PN-25.

Polypropylene pipes for cold water

High-quality polypropylene products can effectively serve up to 50 years as an element for cold water supply. She has proven herself excellent.

For these purposes, you can use products with any marking; it is important that they are of high quality. You just need to choose the right diameter.

Features of the use of polypropylene pipes in the heating system

Products with the following external diameters are used as standard:

for the “warm floor” system - Ø16−18 mm;
for water supply pipes - Ø20 mm;
for risers - Ø25 mm.

The master should pay special attention to the linear expansion of the product, because only hot water will be pumped through it. The higher its temperature, the shorter the service life of propylene pipes for water supply and heating. You should choose products with a low coefficient of thermal expansion.

Installation and distribution of polypropylene pipes: what are the nuances?

To work with PP pipes, you need to have two important tools: a pipe cutter and a special soldering iron. Using the example of pipeline installation, we will show the nuances of the work.

Illustration	Description of actions
	Cutting is done on the floor or table. To ensure the correct size, take into account the height of the clips and bends, as well as other elements.
	You can mark the system map directly on the wall with a pencil or pen, and also pre-attach the clips holding the plastic pipes.
	After the part is heated up, you have only 4 seconds to solder it to the pipe. You should only use a soldering iron with gloves.
	Quickly connect the two parts and secure them. You can pre-treat the soldered edges with a solvent.

The main problem is not to create for yourself hard to reach places for work on weight. Full video available at the link:

What determines the service life of polypropylene pipes for water supply?

There are several main reasons for reduced product life:

constant exposure to sunlight;
high operating temperature of polypropylene pipes;
increased pressure in the system;
low quality material.

To avoid problems, give preference to well-known manufacturers.

Major manufacturers of polypropylene products for water supply

On the Russian PP pipe market you can most often find domestic producers, as well as products from China, Turkey and the EU. European manufacturers have the highest prices, while Russian manufacturers are considered the most budget-friendly.

Good quality and the best price can be offered by such well-known brands as:

Blue Ocean (China);
FIRAT (Türkiye);
Kalde (Türkiye);
Jakko (Türkiye);
PROAQUA (Russia);
PBK (Russia);
Aquatherm (Germany).

The same companies also produce connecting elements.

Article

Is it always safe to use polypropylene pipes for hot water? Are there any preferences in choosing pipes?

Let's summarize the information available to us and draw practical conclusions from it.

Physical properties of the material

Let's start with physical properties the material from which polypropylene pipes are made. Polypropylene is relatively hard; wear-resistant; at a temperature of 140 C it begins to soften; at 175 C it turns into a liquid aggregate state. Melting.

At the same time, most manufacturers declare a much lower maximum operating temperature for theirs - only 95 C. Why is this so?

There appear to be two main reasons.

Economic

If a polypropylene pipe for hot water, on which it is written that it can withstand a maximum temperature of 100 C, becomes deformed or, worse, leaks at 98 C, for a manufacturer in European or American conditions with their tendency to litigiousness, this will mean court. Trial will obviously be a losing battle unless a clear violation of the installation rules is proven.

Payments to the pipe manufacturer will include:

Compensation for the cost of low-quality goods;
Coverage for damage caused by hot water leaks;
Moral damage.

If the first two points are small in terms of production scale, then the latter can make up a very significant part of the profit even for a large manufacturer. And no one wants to lose their money. This is where the low temperature is indicated. If you put hot water into the pipe, that’s your problem.

Technology

You can tighten control of output products and send 20-30 percent of the pipes for scrap and recycling, or you can simply specify the maximum temperature slightly lower so that all pipes obviously fall within the declared parameters. What do you think is more profitable for the manufacturer?

Is the water hot?

Theory

According to those in force in Russia regulatory documents, maximum temperature water in any main line of a residential building, be it heating or hot water supply, should not exceed the same 95 C, and in the case of children's preschool institutions It’s actually 37 degrees.

If so, in theory (note, in theory!) it can be guaranteed that polypropylene pipes for hot water supply will not bring any trouble to the owner.

Practice

But in practice it is worth considering two nuances.

Climate

Our country is huge and includes very different climatic zones. If in Novorossiysk a severe winter is considered to be one during which the temperature dropped below zero for at least twenty days, then in Chegdomyn -50 for three months is a very ordinary phenomenon.

The lower the temperature outside the house, the greater the heat loss through walls, windows and ventilation. And if so, the higher the heat transfer should be heating devices.

There are two ways to achieve this:

Increase the heat transfer area of heating devices. Simply put, surround the room with an entire wall battery.
Raise the coolant temperature.

The dimensions and number of radiators are set by the designers and do not change from the moment the house is commissioned. Yes, a resident can add sections to a cast iron battery or replace it with a more efficient aluminum one. But you don't have to.

At the same time, thermal power plants, heating network maintenance organizations and housing providers are obliged to ensure an acceptable temperature in the apartment in any weather. How do you think this can be done? Right. By raising the temperature of the batteries.

Moreover, in real world it may well exceed a hundred degrees. Water will not turn into steam only due to excess pressure.

Advice: if, with sealed windows and flushed radiators, the temperature in your home drops below +18, you can invite a representative of the housing organization to draw up a report and, on its basis, demand a recalculation for heat.

Sometimes we are talking about very significant amounts. In addition, after drawing up several acts, usually inert homeowners begin to become active and seriously take care of the heat in your home.

Human factor

Water from the supply pipeline of the heating main enters the radiators as usual, having previously been mixed with colder return water. In summer, the hot water supply is supplied directly from the supply.

In winter, when the temperature of the supply water supply is above 90 C (in the batteries it will be 70-75 degrees), it should switch to the return pipeline. In every home and by hand.

If the plumber forgot/ quit/ was drunk, the water in the hot water supply system may be significantly hotter than hundreds of degrees.

You open the tap and a stream of boiling water and steam comes out.

Polypropylene pipes for hot water supply can feel extremely bad in this case.

No need to panic

The above situations are still more likely to be force majeure. In the Far North, it is indeed better to choose for water supply with hot water other materials; however, in most of the country’s territory, SNIP with regard to the temperature of highways is fully maintained - not so much because of the punctuality of all the figures involved in the process, but for reasons of economy.

IN middle lane In Russia, you can safely use polypropylene pipes for hot or cold water supply. If the water temperature is slightly exceeded, do not forget, we know that polypropylene begins to soften only at 140 C.

Reinforcement

Polypropylene pipes have a fairly high coefficient thermal expansion. Remember physics? When heated, all bodies expand. Pipes are no exception. This usually doesn't cause problems.

Polypropylene is a flexible material; somewhere it stretches out a little - in another place it will bend itself. However, there are situations when pipe elongation during heating is undesirable. For example, if a polypropylene pipe for hot water is plastered. Cracks will not decorate the wall in any way.

To reduce thermal expansion of pipes, they are reinforced. The material is aluminum foil up to half a millimeter thick or fiberglass.

Along with reducing the coefficient of thermal expansion, reinforcement also affects the temperature resistance of polypropylene pipes. When the temperature is close to the softening point of polypropylene, and overpressure inside the pipe is large, an ordinary pipe may well be deformed. Reinforced - no.

Tip: with a small difference in price, you should prefer a reinforced pipe with a fiberglass layer.

She:

does not require installation, which will allow you to save a little on tools;
It does not delaminate under any circumstances - the layers in it are not glued, but welded;
Electrochemical processes are completely excluded, which lead, even if there is a small difference in potential inside the pipe, to the gradual destruction of the aluminum layer where it comes into contact with water.

Polypropylene pipes for hot water supply can be safely used everywhere except in the regions of the Far North. Where the temperature of batteries and water in winter can approach a hundred degrees, it is still better to prefer galvanized steel or copper.
For hot water it is preferable.

Polypropylene risers and connections for cold and hot water supply

What is attractive about a polypropylene hot water pipe compared to competing solutions? Can it always be used for DHW needs? Does the installation of a polypropylene hot water supply have any special features? Today we will try to find answers to these questions.

Advantages

The main advantage of polypropylene over other pipes is its very affordable price. Here are a few specific examples from the price list of the Leroy Merlin online store:

Unreinforced pipe PN 20 domestic production, designed for hot water supply needs, with a diameter of 20 mm will cost only 23 rubles per linear meter;

A fiber-reinforced pipe of the same diameter costs 40 rubles per meter, and one reinforced with aluminum foil costs 57 rubles;
A coupling for connecting 20 mm pipes will please the buyer with a price tag of only 2.8 rubles, a tee of the same size costs 5 rubles 70 kopecks.

Please note: the closest competitor in terms of pipe prices is metal-plastic. With the same outer diameter as polypropylene, it is only slightly more expensive than an aluminum-reinforced hot water pipe. However, fittings for metal-plastic (compression and for crimping with a sleeve) are 10-15 times more expensive than polypropylene ones, which on the scale of a water supply creates a more than noticeable difference in price.

Fittings for polypropylene pipelines are structurally simple and therefore extremely cheap

However, low cost would not have played a decisive role if not for other properties of polypropylene:

Pipes are durable. In hot water they last at least 25 years, in cold water - even from 50. Compare their resource, for example, with the service life of black steel in water supply (15 years);
The smooth inner surface of polypropylene pipes does not become overgrown with deposits. Therefore, the throughput of the water pipeline does not decrease and its hydraulic resistance does not increase over time;

For comparison: when designing steel water pipelines, it is necessary to take into account the increase in the roughness coefficient during operation, deliberately overestimating their diameter.

Welded connections with fittings are maintenance-free. They are stronger than a solid pipe and can be installed in ties and grooves;

The appearance of the pipeline is preserved for decades. It does not need to be periodically painted or cleaned of rust;
Polypropylene is a dielectric, which eliminates electric shock when, for example, neighbors try to save electricity by grounding electrical appliances to the water supply;
It has low thermal conductivity. This means that the hot water in the pipes will cool more slowly, and the risers and cold water supply lines will not become covered with condensation in the summer heat.

Applications

Is it always possible to use polypropylene pipes for hot water supply?

Banned

Here are the standard characteristics of a polypropylene pipe intended for domestic hot water needs.

Working pressure - up to 20-25 atmospheres;
Operating temperature - up to 95 degrees with the possibility of a short-term increase to 120°C.

The characteristics of the pipe are usually indicated in its marking

There is a caveat: the given operating pressure values are valid for a temperature of +20°C. At a maximum of 90 degrees it drops to 8-9 kgf/cm2. The pipe service life of 25-30 years also remains relevant only within a strictly defined range of operating temperatures - up to +70°C.

Formally, the given characteristics fit into the typical parameters of both autonomous and centralized hot water supply (the latter is characterized by a water temperature of 60-75 degrees at a pressure of 3-7 atmospheres).

However, everything is smooth only as long as DHW system apartment building works normally. Here are some of the most common force majeure situations:

DHW operation from supply elevator unit at the peak of cold weather. Supply temperature according to temperature chart heating main operation can reach 150 degrees. When the supply temperature exceeds 80 degrees, the hot water supply must switch to the return water supply, however, the forgetfulness of plumbers can play a bad joke on the owner of the polypropylene water supply;

During testing of heating mains and heating systems for temperature, hot water must be turned off. However, a faulty valve or human factor can again lead to water superheated to 150°C flowing into the pipes;
Finally, the fall of the valve cheeks or the rapid filling of the hot water circuit can lead to water hammer - an instant increase in pressure at the front of the incompressible fluid flow to 30 atmospheres or more. Water hammer lasts a fraction of a second, but this time is often enough to destroy a water supply system.

Conclusion: it is dangerous to use polypropylene for central hot water supply with water supplied directly from the heating main through the elevator tie-in (the so-called open system heat supply).

Allowed

Polypropylene can be unconditionally used in:

(with hot water preparation in boilers and instantaneous water heaters). The water pressure in them is always equal to the pressure in the cold water system and falls within the range of 1.5 - 5 kgf/cm (up to 6-7 atmospheres if there is a powerful pump in the house), and the temperature is limited by the thermostat of the heating device;

Centralized hot water supply systems in houses with closed circuit heat supply (without taking water from heating mains). In them, hot water is heated by heat exchange with the coolant, while the hot water supply and heating circuits are not connected. Accordingly, water hammer and temperature surges in the heating main will not have any effect on the operating parameters of the internal water supply system.

Reinforcement

It is executed:

Image	Reinforcement type
	Aluminum foil glued between two layers of polypropylene.
	Fiber (chopped mineral fiber) included in the middle layer of polymer in the pipe structure

Useful: three layers of fiber-reinforced pipe are formed on one extruder and reliably fused to each other due to the production technology itself. In the production of pipes with aluminum reinforcement, the quality of the product greatly depends on the quality of the glue used and adherence to the technology.

It is believed that the task of reinforcement is to ensure maximum tensile strength of the pipe. Indeed, a maximum operating pressure of 25 atmospheres is typical for reinforced pipes; however, the functions of the reinforcing layer do not end there.

One of the features of polypropylene is its extremely high elongation coefficient when heated. When submitting to polypropylene water supply With room temperature of water heated to 70 degrees, each linear meter will lengthen by 6.5 mm (versus, for example, 0.5 mm for a steel pipeline).

Reinforcement significantly reduces dimensional change when heated:

Fiber reduces elongation to 3.1 mm;
Aluminum foil is even more effective: with it, polypropylene pipes reinforced for hot water supply elongate by only 1.5 mm/m when heated to 50°C.

Plumbing assembly

Method of installation of polypropylene pipes - low temperature soldering. The surfaces of the pipe and fitting are melted upon contact with the Teflon nozzle of the soldering iron and are aligned with each other. Thanks to molecular diffusion, the plastic of the parts is fused into a single whole, and after cooling, the connection is ready for operational loads.

How to solder

How long does it take to heat the pipe and fitting with a soldering iron? Comprehensive instructions are contained in the appendix to SNIP 2.04.01-85, which describes correct installation polypropylene.

Outer diameter of water supply, mm	Heating, sec	Connection time, sec
16	5	4
20	5
25	7
32	8	6
40	12
50	18

Do-it-yourself plumbing soldering has several subtleties.

When combining a pipe and fitting with a soldering iron nozzle and when connecting parts to each other, they must not be rotated around the longitudinal axis. When turning, waves will remain on the surface of the plastic, which will reduce the quality of the connection, leaving cavities inside the fitting;
Soldering can begin no less than five minutes after turning on the soldering iron;
The connection can be subjected to operational loads only after complete cooling (2 minutes for diameters 16-25 mm and 4 minutes for diameters 32-50 mm);
Polypropylene hot water supply pipes reinforced with aluminum need to be stripped before welding with a fitting. A shaver or trimmer (these tools differ only in the position of the knives) removes the outer or inner layer of foil, allowing welding to combine the fitting with the inner polymer shell of the pipe.