Why do you need an expansion tank for water supply? Tank for water supply. Open type expansion tanks

Expansion membrane tank– a mandatory component, without which the functioning of the system is not possible. It is he who creates the necessary pressure for the full operation of the water supply system, makes reserve water reserves and even performs a number of protective functions. In connection with such a high importance of equipment, the question naturally arises: how to choose and correctly install a tank? To understand, let's approach the issue comprehensively: we bring to your attention the structure and operating principles of the expansion device, its types, selection features, as well as the connection diagram and useful instructions on setup with video.

Functions and operating principle

A membrane tank is a sealed, predominantly metal tank, consisting of two separated chambers: air and water. A special rubber membrane acts as a separator - it is usually made of strong butyl, which is resistant to the development of bacterial microorganisms. The water chamber is equipped with a pipe through which water is directly supplied.

The main task of the expansion membrane tank is to accumulate a certain volume of water and supply it at the user’s request under the required pressure. But the functions of the device are not limited to this - it also:

• protects the pump from premature deformation: thanks to the water reserve, the pump does not turn on every time the tap is opened, but only when the tank is empty;
• protects against changes in water pressure when using several taps in parallel;
• protects against hydraulic shocks that could potentially occur when the pumping unit is turned on.

Operation of the device

The principle of operation of the tank is as follows. When the pump turns on, water begins to be pumped into the water chamber under pressure, and the volume air chamber decreases at this time. When the pressure reaches the maximum allowable level, the pump turns off and the water supply stops. Then, as water is drawn from the tank, the pressure decreases and, when it decreases to the minimum allowable level, the pump turns on again and resumes pumping water.

Advice. During operation of the tank, air can accumulate in the water chamber, which causes a decrease in the efficiency of the equipment, so at least once every 3 months it is necessary to carry out maintenance of the compartment - to bleed excess air from it.

Types of membrane tanks

There are two types of expansion membrane tanks:

Advice. When choosing between a replaceable and permanent membrane, consider one important factor: in the first case, the water is completely in the membrane and does not come into contact with the inner surface of the tank, which eliminates corrosion processes, and in the second case, the contact is maintained, so achieve maximum protection from corrosion is impossible.

Features of choosing a tank

The main factor in choosing a membrane tank is its volume. When calculating the optimal tank volume, the following nuances should be taken into account:

• number of users of the water supply system;
• number of water intake points: taps, outlets for showers and Jacuzzis, outlets for household appliances and boilers that work with water;
• pump performance;
• the maximum number of pump on/off cycles in one hour.

To calculate the approximate volume of the tank, you can use the following guidelines from experts: if the number of users is no more than three, and the pump capacity is no more than 2 cubic meters per hour, then a tank with a volume of 20-24 liters is quite sufficient; if the number of users is from four to eight, and the pump performance ranges from 3-3.5 cubic meters per hour, a tank with a volume of 50-55 liters will be required.

When choosing a tank, remember: the more modest its volume, the more often you will have to turn on the pump and the higher the risk of pressure drops in the water supply system.

Advice. If you assume that over time there will be a need to increase the volume of the membrane tank, buy equipment with the ability to connect additional containers.

Tank connection diagram

The membrane tank can be installed either vertically or horizontally, but in both cases the connection diagram will be identical:

1. Determine the installation location. The device must be located on the suction side circulation pump and before the branching of the water supply. Make sure that there is free access to the tank for maintenance work.
2. Secure the tank to the wall or floor using rubber pads and ground it.
3. Connect a five-pin fitting to the tank nozzle using an American fitting.
4. Connect in series to the four free terminals: a pressure switch, a pipe from the pump, a pressure gauge and a distribution pipe that supplies water directly to the intake points.

Tank connection

It is important that the cross-section of the connected water pipe is equal or slightly larger in relation to the cross-section of the inlet pipe, but in no case should it be smaller. One more nuance: it is advisable not to place any technical devices, so as not to provoke an increase in hydraulic resistance in the water supply system.

Equipment setup instructions

After the membrane tank is installed and connected, it is important to properly configure and start it up. Let us dwell on the main points of this stage.

The first step is to find out the internal pressure of the tank. In theory, it should be 1.5 atm, but it is possible that a leak occurred during storage of the device in a warehouse or during transportation, which caused a decrease in such an important indicator. To make sure the pressure is correct, remove the spool cap and take measurements with a pressure gauge. The latter can be of three types: plastic - cheap, but not always accurate; mechanical automobile - more reliable and relatively affordable; electronic – expensive, but extremely accurate.

After measurements, you need to decide which pressure will be most optimal in your case. Practice shows that for normal functioning plumbing and household appliances, the pressure in the membrane tank should vary within 1.4-2.8 atm. Let's say you've chosen these metrics - what next? First, if the initial pressure in the tank is below 1.4-1.5 atm, it must be increased by pumping air into the corresponding chamber of the tank. Then you should set the pressure switch: open its cover and use the large nut P to set the maximum pressure value, and use the small nut ∆P to set the minimum value.

The process of setting up equipment is simple

Now you can start the system: as water is pumped in, watch the pressure gauge - the pressure should gradually rise, and after it reaches the maximum set point, the pump should turn off.

As you can see, without an expansion membrane tank you really can’t even count on the full operation of your individual water supply. Therefore, if you want to uninterruptedly enjoy the benefits of civilization, carefully approach the selection and connection of the device - all the principles and subtleties are before you, so we advise you to study them well and only then proceed to active actions.

Calculation of accumulator volume: video

Membrane expansion tank for water supply: photo

The expansion tank for water supply, operating principle and design, types and features are discussed in detail. The criteria for choosing an expansion tank are presented, the disadvantages and the main purpose are considered.

Figure 1: Types of expansion tanks

The most important condition in a water supply system this is optimal support for water pressure. To ensure the correct pressure in expansion tanks, compensators are used to equalize the load on pipes and equipment. Water is used not only in technical, but also in food purposes, so the tank and membrane with inside made of special material that does not change the taste and smell of water. This material must meet sanitary and hygienic requirements and must have a quality certificate. Expansion tank for water supply systems it compensates for hydraulic shocks, which significantly increases the service life of pumps and pipelines.

Expansion tank device

Inside the expansion tank there is a rubber membrane that divides the tank into two chambers: air is pumped into one chamber, and the other chamber remains empty. After installing and starting the heating, coolant will begin flowing into the empty chamber. In another chamber where air is pumped, the required volume will be restored. When the liquid cools, it is forced back into the water supply. Thus, the pipes maintain a constant, necessary pressure, which is why the system always works stably, there are no overloads or pressure surges.

Figure 2: Dimensions of expansion tanks

The water coming from the well is under pressure, and at this time the membrane increases, the volume of air decreases, and some pressure is created. The pump turns off when the pressure reaches the required level. Water is consumed, pressure drops accordingly, and the pump turns on to maintain pressure. The disadvantage of an expansion tank is that it is an irrational method of temporarily storing water. The Dutch were the first to propose the use of expansion tanks with a membrane. Today, closed expansion tanks are very aesthetically pleasing and come in a variety of designs.

Figure 3: Expansion tank in action

A membrane expansion tank for water supply also has a drawback, which is that the membrane of this design cannot be replaced. If the heating system is working normally, the liquid expands when water starts, but otherwise pressure fluctuations occur smoothly. The membrane of such a tank is made of quality material and lasts a very long time.

Figure 4: Diaphragm expansion tank for water supply

Advice! Don't forget to check the air pressure before each heating season. For systems that have large volumes, it is best to use a stationary pressure gauge. (See also:)

With the help of a membrane expansion tank, hydrodynamic shock is compensated, which greatly reduces the frequency of pump operation. This design increases service life and saves electricity. When the coolant is heated or cooled, the system remains intact. This compensates for the volume of changes and this is why a membrane expansion tank is installed. Even during a power outage, the reserve tanks have a fire extinguishing function. Membrane tanks can be used not only in household systems, but also in industrial, since working pressure rated up to 16 bar. Hydraulic accumulators can be horizontal and vertical, open and closed. In addition, they differ in water volume and operating pressure.

Tank volume

In order to find out the volume of the tank, you need to calculate using the formulas the initial air pressure in the tank and the operating pressure, at maximum load. But it will be enough for the buyer to know that the volume of the tank is 1 to 10 of the volume of coolant that is located in the system.

Figure 5: Calculation of expansion tank volume

Important! If the tank volume is not selected correctly, the heating system will not last long. Even with the most high temperature heating, the pressure in the heating system should in no case exceed the permissible level. (See also:)

Expansion tank for water supply, installation instructions are included with each tank. There you need to look at the features of choosing an expansion tank depending on your needs and characteristics heating system.

Open type expansion tanks

They are installed at the highest points of the heating system: on the roofs of buildings or attics. Thermal expansion The coolant prevents the water from boiling and if a leak occurs, the heating system is replenished with water. Today the tanks open type They are installed in few places, because they have some disadvantages:

• the structure is too large;


• installed at a high point in the heating system, and for this you need to purchase extra pipe(there will be heat loss);
(See also:)

• air enters the heating system through the tank, corrosion forms on the heating devices and on the heating systems of some parts;


• cannot work stably under high pressure.

Figure 6: Expansion tank diagram

1. Frame;


2. Water level;


3. Pipe cold water;


4. Drain pipe;


5. Safety valve;


6. Shut-off valve;


7. The highest point in the pipeline riser.

Closed expansion tanks are used:

• in a heating system that operates with autonomous sources warmth;


• in a heating system that is connected to centralized networks compiled according to independent schemes;


• in a system that is connected to solar collector and pumps;


• in a system connected to cold and hot water supply.

Selection of expansion tank

You need to choose an expansion tank taking into account all the features of the system. First you need to select the required volume, choose a design, and decide on the membrane material. It is also worth paying attention to the weight of the product, which is why the indicator can determine the quality of reliability and durability of the expansion tank. It is better to purchase well-known brands, as they will be able to ensure long-term operation of the heating system and prevent breakdowns in the system. The installation of an expansion tank for water supply and the price for it will please everyone who needs to install such a tank.

Use of materials is permitted only if there is an indexed link to the page with the material.

Today no one will be surprised by an autonomous water supply system. Such designs are very convenient and practical, but their operation often requires devices that a person who uses only a centralized water supply may simply not know about. For example, an autonomous water supply system will long time work uninterruptedly only if an expansion tank for water supply is included in it. Modern industry produces many of the most different models such devices. To choose the best option for yourself, you need to navigate the types of equipment and have a good understanding of the principle of its operation.

Design and functions of this equipment

Types of membrane tanks

There are two main types of expansion membrane equipment.

Device with replaceable membrane

Home distinctive feature– possibility of replacing the membrane. It is removed through a special flange, which is held on by several bolts. It should be taken into account that in large-volume devices, in order to stabilize the membrane, it is additionally secured with its rear part to the nipple. Another feature of the device is that the water filling the tank remains inside the membrane and does not come into contact with internal part tank. What protects metal surfaces from corrosion, and water itself from possible contamination and significantly extends the life of the equipment. Such models are produced in both horizontal and vertical versions.

Devices with a replaceable membrane differ more for a long time service, since the most vulnerable element of the system can be replaced and water does not come into contact with the metal body of the device

Device with a stationary diaphragm

In such devices, the inside of the tank is divided into two parts by a rigidly fixed membrane. It cannot be replaced, therefore, if it fails, the equipment will have to be replaced. One part of the device contains air, the other contains water, which is in direct contact with the internal metal surface device, which can provoke rapid corrosion. To prevent metal destruction and water pollution inner surface the water part of the tank is covered special paint. However, such protection is not always durable. Devices are available in horizontal and vertical types.

A type of device with a rigidly fixed membrane. The design assumes that water is in contact with the walls of the equipment

In our next material Expert recommendations for choosing a membrane tank are presented:

How to choose the right device?

The main characteristic on the basis of which equipment is selected is its volume. In this case, the following factors must be taken into account:

• Number of people using the water supply system.
• The number of water intake points, which include not only showers and taps, but also household appliances, for example, washing machine and dishwasher.
• The likelihood that water will be consumed by several consumers at the same time.
• Limit number of start-stop cycles per hour for the installed pumping equipment.

• If the number of consumers does not exceed three people, and installed pump has a capacity of up to 2 cubic meters. m per hour, a tank with a volume of 20 to 24 liters is selected.
• If the number of consumers is from four to eight people and the pump capacity is within 3.5 cubic meters. m per hour, a tank with a volume of 50 liters is installed.
• If the number of consumers is more than ten people and the productivity of the pumping equipment is 5 cubic meters. m per hour, choose an expansion tank of 100 liters.

When selecting the desired model device, it is worth considering that the smaller the volume of the tank, the more often the pump will turn on. And also the fact that the smaller the volume, the greater the likelihood of pressure surges in the system. In addition, the equipment is also a reservoir for storing a certain supply of water. Based on this, the volume of the expansion tank is adjusted. You should know that the design of the device allows the installation of an additional tank. Moreover, this can be done during the operation of the main equipment without labor-intensive dismantling work. After installing the new device, the volume of the tank will be determined by the total volume of the containers installed in the system.

In addition to technical characteristics, when choosing an expansion tank, special attention should be referred to its manufacturer. The pursuit of cheapness can result in much more significant expenses. Most often, to produce models that are attractive for their cost, the cheapest materials are used, and, as practice shows, they are not always of high quality. The quality of the rubber from which the membrane is made is especially important. Not only the service life of the tank, but also the safety of the water that comes from it directly depends on this.

When purchasing a tank with a replaceable membrane, be sure to check the cost of the consumable element. Very often, in the pursuit of profit, not always conscientious manufacturers significantly increase the price of a replacement membrane. In this case, it will be more appropriate to choose a model from another company. Most often, a large manufacturer is ready to be responsible for the quality of its products because it values ​​its reputation. Thus, it is worth considering models from these brands first. These are Gilex and Elbi (Russia) and Reflex, Zilmet, Aquasystem (Germany).

The volume of the expansion tank for water supply may vary; it is selected based on the needs of the users. If a larger volume is subsequently required, an additional device can be installed

Features of self-installation

All expansion tanks can be divided into two groups, determined by the connection method. There are vertical and horizontal models. There are no special differences between them. When choosing, they are guided by the parameters of the room where the equipment will be located. During the installation process, you should adhere to the following recommendations:

• The expansion tank is installed in such a way that it can be easily accessed for maintenance.
• It is necessary to provide for the possible subsequent dismantling of the connecting pipeline to replace or repair the equipment.
• The diameter of the connected water supply cannot be less than the diameter of the pipe.
• The device must be grounded to avoid electrolytic corrosion.

The device is installed on the suction side of the pump. In the section between the pumping equipment and the connection point, it is necessary to exclude all elements that can contribute significantly hydraulic resistance into the system. We connect the make-up line to the circulation circuit of the entire system.

According to the type of installation, expansion tanks of horizontal and vertical connection are distinguished

Please also pay attention to the material about what malfunctions most often occur in pumping stations, and how to fix them yourself:

The expansion tank is an integral part of an autonomous water supply system. It supports, prevents premature damage to the pump and retains a certain supply of water. However, all these functions are performed only if the structure is correctly selected and installed correctly. Therefore, if you lack experience, it is better not to get carried away with amateur activities, but to find qualified specialists who will install any device with high quality.

The water supply system, as well as the heating system, is very important, especially during the cold season. The expansion tank for cold water is an important element. From him technical condition and characteristics directly depend on reliability and service life. The material will discuss how to implement optimal choice unit and instructions for its installation will be provided.

Types of expansion tanks for water

The water expansion tank is one of the main components of the water supply system. Traditionally, there are two main types of expansion tanks for water: open and closed (membrane) type. Let's look at them in more detail.

Open type expansion tank. It is represented by a container connected in a special way to the water supply system. Water tanks of this type are usually placed at the top of the building (usually in the attic) because they are bulky and have no aesthetically pleasing and not sealed. To minimize heat loss through the walls of an open-type water tank, they are often thermally insulated.

Diaphragm expansion tank for water

Diaphragm expansion tank for water. The most commonly used option in residential premises. Presented in a sealed container in the form of a capsule made of metal. Its internal cavity is divided into two parts by a heat-resistant rubber membrane. As a result, two cavities are formed: liquid and air. In the air compartment there is a valve designed to release excess air when the pressure increases significantly.

Main functions of a closed type water tank

The main function of the water expansion tank is to maintain a stable and optimal pressure for the water supply system. Most often, it is the membrane structure that is used for these purposes, so we will talk about the main functions that the membrane tank performs:

• supports constant pressure in the system, even if the pump is not functioning;
• prevents the occurrence of water hammer caused by a sudden voltage drop or the presence of air in the pipes;
• maintaining a certain volume of water under pressure, which ensures its supply to any water intake point. Thus, a tank with a volume of about 30 liters can provide one point with water for several minutes.
• protection of pumping equipment from rapid wear.

When choosing an expansion tank, special attention should be paid to two characteristics: the volume of the tank and the membrane, namely its quality and performance characteristics. But more on that a little later.

In turn, how to understand what volume of expansion tank will be most suitable? And here we should proceed from the following points:

• The maximum possible number of start-up cycles performed by pumping equipment.

Advice. When choosing a tank of a certain volume, remember: the smaller it is, the more often the pump will turn on. Accordingly, the likelihood that it will fail much earlier than expected increases.

• Water intake points, namely their number. And implied in in this case not only all sinks and bath/shower, but also all household appliances powered by mains ( dishwasher, washing machine, etc.).
• The number of people living in the apartment/house.
• Possibility of drawing water from several points at the same time.

The volume of the tank depends on the number of residents in the house

A few words about the membrane. After you are convinced that it is made of sufficiently durable and high-quality material, pay attention to the following indicators:

• service life specified by the manufacturer;
• compliance with sanitary standards;
• operating temperature range;
• lack of possibility of diffusion.

If you have never particularly dealt with equipment like an expansion tank, then when choosing a unit, be guided by a few numbers.

1. First indicator. A family of one to three people and a pump with a capacity of no more than 2 tons of water per hour – the best option there will be a tank with a volume of 20-25 liters.
2. Second indicator. A family of 3 to 8 people and the pump capacity is no more than 3.5 tons of water per hour - here you can’t get by with 25 liters, the volume of the tank should be at least twice as large.
3. Third indicator. Very high consumption water - a volume of about 100 liters would be appropriate.

You also take into account the fact that a small tank provokes frequent pressure surges in the system.

Often the design of the expansion tank provides for the installation of an additional water tank, without any complications. In the future, the volume of the unit is considered to be the volume of all containers located in the system.

Self-installation

Before moving on to the issue of installation, let us clarify one point: the type of tank. They are horizontal and vertical. And this is important to consider when installing the structure. Otherwise, any membrane tank is installed according to a similar principle.

Installing a water tank

If you want to do this yourself, then you should have at least a little experience working with water pipes. In general, the installation process is quite simple, the main thing is to follow a few rules:

1. The tank must be installed taking into account the need for access to it for preventive/repair measures.
2. The tank must be connected to the pipeline using special quick-release connectors so that in certain situations it is possible to disconnect the unit from the network.
3. The diameter of the pipeline must be no smaller than the cross-section of the inlet pipe.
4. The expansion tank housing must be grounded to avoid electrical corrosion.
5. There should be no equipment between the tank and the pump that could increase hydraulic resistance.

Our article is coming to an end. Its purpose was to provide basic information about expansion tanks, including selection criteria and rules for quality installation. If you are confident enough in your abilities, go for it, but if not, we still advise you to entrust the installation work to a professional.

Expansion tank: video

Expansion tank for cold water: photo

On suburban areas, not equipped central water supply, there is a need to supply water yourself. However, digging a well or a borehole and simply installing an electric pump is clearly not enough for several reasons: the water pressure is maintained at a limited distance, which decreases further taking into account the depth of the well, the number of starts in a certain period of time is strictly regulated to avoid premature failure. To maintain pressure in autonomous system include an expansion tank for water supply, which accumulates a certain amount of liquid and allows the pump not to turn on when the tap is opened for a short time. In addition, in case of power outages, a water supply is created and water hammer is compensated, which protects household appliances: boilers, washing machines.

Water supply tanks are metal containers, one part of which is filled with air and the other with liquid. Horizontal or vertical orientation makes no fundamental difference; for each specific case, a form is selected that will most conveniently install the unit in its intended place.

According to the principle of operation, there are expansion tanks:

• open type;
• membrane (closed), also called hydraulic accumulators, or expanzomats.

The connection diagram of the tanks into the drinking water supply system depends on the type. The first one is simple large capacity. There is a lid here, but it does not serve for sealing, but rather as protection from debris. The tank is placed at a point significantly higher than the disassembly site, most often in the attic, and when the tap is opened the water is flowing by gravity. These devices are used very rarely, as they have a number of significant disadvantages:

• it is necessary to install an automatic relay to turn off the pump when the tank is filled;
• open contact with air leads to oxygen entering the water, which promotes corrosion metal parts;
• it is necessary to insulate the room with installed tank to prevent it from freezing in winter.

In hydraulic accumulators, a metal container is divided into two parts by a special membrane, into one of which air is pumped, and the other is intended for water. The design is sealed; as the liquid enters, it takes up more and more space, stretches the membrane and compresses the adjacent chamber. When the air resistance reaches a predetermined value, the pump automatically stops and resumes after the reserve is consumed from the tank and the pressure drops to a certain minimum. It should be borne in mind that the maximum volume of water is only a third of the total capacity of the unit, that is, for example, expansion membrane tanks for water supply per 100 liters accumulate 33 liters of liquid.

Basic criteria for choosing a hydraulic accumulator

To calculate the optimal volume of the tank, you need to determine the number of consumers of the future water supply. Moreover, this does not mean the number of people living in the house, but the connected household appliances(dishwasher, boiler) and taps (toilet, faucet, shower). The calculations take into account the probability of simultaneous use of several points, based on their results and practical experience Experts have come up with the following diagram:

• up to 3 consumers - 20–24 l;
• 4–8 - 50–60 l;
• over 10-100 liters or more.

If the developer offers to buy tanks for automated systems water supply - we're talking about about the station, consisting of a pump, a hydraulic accumulator and a complex control unit. For this purpose, a horizontal tank is usually chosen (it is easier to mount it on surface pump), equipped check valve, preventing arbitrary drainage of water into the well after shutdown. In addition, in technical documentation it must be indicated that the accumulator can be used for drinking water supply. The words “do not comply with DIN1988 standards” in the passport of an imported unit mean that it is intended only for technical or utility water.

It is important to pay attention to the possibility of repairing and servicing the expansion tank, and not just study the prices of expansion tanks for water supply systems. In particular, hydraulic accumulators come in two types: balloon and membrane. This division is quite arbitrary, since both have a membrane in their design, which in the first case is attached to the inlet, is a replaceable part and does not allow water to come into contact with the metal body, and in the second case it is installed deep in the tank and cannot be repaired. It is preferable to purchase a cylinder hydraulic tank that is not subject to corrosion, where almost all parts are replaceable.

Heating options

Externally, all household hydraulic accumulators look the same, but types for heating are designed not to create the required pressure, but to prevent its increase. Miscellaneous device tanks for cold and hot water supply systems does not allow them to be replaced with each other. As the coolant heats up, its volume increases, and the pressure in the heating pipes increases. In order to prevent leaks, as well as to remove air, an expansion tank is connected to the circuit, which receives excess liquid.

into the heating system with natural circulation You can put an open tank. It is rarely used due to the abundance of inconveniences that arise during use. The tank is located only at the highest point of the heating circuit; direct contact of water with air promotes corrosion of metal parts, evaporation of the coolant occurs, the level of which must be monitored and topped up as needed. Membrane tanks are installed at any point in the circuit closed type. To maintain stable operation heating units are equipped with a compressor; air is released when the pressure increases or pumped in when it decreases. In addition, evaporation of the coolant from the sealed tank is excluded.

When calculating the capacity of the expansion tank, it should be taken into account that when heated, the volume of water increases by approximately 0.3% every 10 °C. It is also necessary to pay attention to whether the selected model supports the operating parameters of the system and the type of coolant. Specifications usually indicated in the accompanying documentation.

For example, small Reflex tanks N and NG series are designed for closed heating circuits using water or glycol solution with a concentration of up to 50%. The membrane in all versions is non-removable, nominal volume from 8 to 5,000 l, maintained pressure 6, 10 or 16 bar, operating temperature tank 120 °C, membrane - 70 °C.

The cost of equipment varies depending on its capacity:

• NG 18 (12 l, 3 bar) – 1,440 rubles;
• NG 50 (50 l, 6 bar) – 4,410 rubles;
• NG 100 (100 l, 6 bar) – 9,630 rubles.

Expansion machines for hot water supply

Basically, boilers are installed in autonomous water supply systems for heating, but there is an option when liquid from the heating system is used for hot water supply. In this case, it is important to choose the right expansion tank, which should not only support the required functional parameters, but also comply additional requirements. The membrane and other parts with which water comes into contact are made of materials that meet hygienic standards for devices working with drinking liquid.

Products domestic producers

Gilex tanks for heating and water supply systems successfully compete with the products of well-known foreign companies, without losing at all in quality, but offering hydraulic accumulators to the consumer at a higher price. low prices. Expansion tanks for closed circuit have a steel body, a membrane made of ethylene-pylene-diene monomer (EPDM) is removable on devices starting from 24 liters. Depending on the nominal volume, the price is: 18 l - 1170 rubles; 50 l - 2750; 100 l - 5300.

One more Russian company, whose main products are heating boilers, offers customers the Evan membrane tank. Hydraulic accumulators of the same class produced by Evan and Gilex cost almost the same: the version with a nominal volume of 100 liters and a maximum operating pressure of 10 bar is 3,250 and 3,400 rubles, respectively.