How to choose an instantaneous electric water heater: tips and introduction to successful models. How to choose a good instantaneous electric water heater

They have such significant advantages over storage ones as compact sizes and instant water heating. But connecting them requires a separate electrical cable and a circuit breaker on the switchboard.

Therefore, the installation of flow-through heaters is limited in apartments multi-storey buildings old buildings - here you can install a heater with a power of no more than 3.5 kW.

Calculation of required power

The power of a water heater can be determined by knowing the exact list of purposes for its use. For this You can use the table, which shows the approximate volume of water required for various needs:

The power of an instantaneous electric water heater is calculated using the formula:

P=G*∆t/14.3 where:

• P - heater power, kW;
• G - flow rate (flow), l/min;
• ∆t - required temperature increase, º C; ∆t = T- tin;
• T - desired (required) outlet temperature, º C;
• tin - cold water temperature, º C; (winter) +5º C, (summer) +15º C.

This indicator can be determined by a more simplified method - simply divide in half the power of the water heater you like. The result is a fairly accurate water flow (in l/min) when heating it by 20-30º C. For clarification, here is an example: a 16 kW water heater will provide a water flow of 8 l/min, which is quite enough for taking a shower.

If hot water is needed at several points, not just for the shower, then you need to focus on the capacity of the largest water intake point. If it is necessary to use these points at the same time, then the power of the selected instantaneous water heater must be increased by at least one and a half times.

Based on these calculations, it becomes clear that you can get a lot hot water you can immediately use a small instantaneous water heater if its performance is at least 8 kW.

This is only possible in new houses and houses with installed electric stoves. More powerful instantaneous electric water heaters (from 12 to 36 kW) are installed in country houses and cottages with specially designed and installed electrical equipment to provide the required electrical power. In this regard, single-phase and three-phase instantaneous water heaters are produced.

Pressure and non-pressure instantaneous water heaters

Flow-type water heaters are also divided into pressure and non-pressure. Pressure electric heaters (they are also called “system heaters”) allow you to use water from any tap installed in the house. They are embedded in hot and cold water pipes. This is convenient during the period when the centralized hot water supply is turned off. Switching on and off of such a water heater occurs automatically; it reacts to the flow of water.

The set of non-pressure flow heaters, which are produced with a power from 3.5 to 8 kW, includes showers and kitchen attachments. They work only at one water intake point. Such heaters are convenient to use in summer time in the country.

The cost of non-pressure instantaneous water heaters is low, and in most cases they are all included kitchen faucet or shower head. And if the water intake points are remote from the water heater, it is profitable to buy them for each water intake point separately - this will significantly save electricity on heating water in the pipes. That is why such water heaters are often purchased for summer cottages.

Since a gravity heater cannot provide a large amount of water, the holes in the shower heads of the heaters are specially made very small to ensure a stronger stream. If the water is very hard, it is necessary to rinse the nozzles more often with a descaling solution, otherwise the holes may become clogged and overheating of the device will be inevitable.
Most low-power, non-pressure instantaneous water heaters are designed for use in countries with warm climates, where average annual temperature fluctuations are small.

Therefore, in winter middle lane they will be ineffective since they can heat water to no more than 30º C.

Review of brands and manufacturers. Price comparison

In the market of electric water heaters, instantaneous heaters are represented by the following manufacturers:

1. Electrolux and Timberk (Sweden);
2. AEG, Clage (Germany);
3. Thermex (Italy);
4. Redring (England);
5. Kospel (Poland).

Let's compare the characteristics and prices of some well-known brands

Instantaneous electric water heaters Electrolux

Electrolux produces several series of heaters of varying performance, which are equipped with additional functions.

Swedish brand water heaters equipped with an efficient heating coil element, reliably protected from scale. Dear models equipped with a highly intelligent control system.

Instantaneous electric water heaters Thermex

The heating element of Thermex devices is equipped with a special ceramic filler, and the flask is made of copper High Quality. Water heaters of this class produced by the company - optimal ratio in terms of price and quality.

Instantaneous electric water heaters Kospel
The Polish company produces mainly system models, but also several brands of non-pressure heaters - the STREAM and EPJ series (small with mixing fittings). Components in contact with water are made of high-quality brass and copper. Kospel instantaneous water heaters have a nice design, modern, and service maintenance low-cost.

Let's sum it up

Having decided on the power of the electric heater, before ordering in an online store or going to a specialized store, it would be useful to:

1. Check with your service provider about network capabilities., to which the house is connected, and what additional electrical equipment will be needed to connect the selected instantaneous electric heater.
2. Determine the complexity of installing the device and understand whether it is possible to cope with it yourself or whether it is necessary to invite specialist electricians and plumbers, find out the cost of installation work and installation.
3. Before you choose electric water heater flow type It’s worth asking about warranties, availability of replacement parts, and their cost. and find out where the service centers closest to your home are.

This will help save time, effort and money.

To consolidate the information received, I suggest watching the video:

Agree, it’s great when hot water always flows from the tap, regardless of its supply from the city utility company. The problem of interruptions will be solved by installing an instantaneous water heater. But the variety of offers on the market is amazing, and you want to buy best model and don't know which one to choose?

We'll show you how to choose instantaneous water heater, having the necessary technical characteristics. We'll tell you how to choose it taking into account operating conditions. Let us indicate what capabilities the equipment should be equipped with to meet the individual needs of users.

The article discusses the main selection criteria optimal model, the rating of the most popular water heaters is given. Attached are photographic materials and useful video recommendations that will help you decide on the best flow machine.

The design of an instantaneous water heater is not complicated: in metal or plastic case a small water tank is enclosed, equipped with heating elements or a spiral.

Budget appliances most often have 1-2 heating elements, which have weakness: heating elements quickly become overgrown with scale. The good news is that they are easy to replace.

Less scale is formed in devices with a spiral enclosed inside copper tube. The disadvantage of such a device is a negative reaction to bubbles and air pockets. If the equipment fails, replacement will be expensive.

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The heating principle is simple: cold water enters the tank, comes into contact with hot elements, heats up and comes out with the required temperature parameters (on average from + 40 °C to + 60 °C).

To install compact equipment, you need a mounting kit, water supply and electrical cable.

Schematic representation of a household flow-through electrical device with an electronic control unit, in which water is heated using a copper heating element

Powerful equipment designed for several water points requires good flow and high pressure. Non-pressure devices operating at low pressure can sufficiently serve only one tap.

For this reason, they are initially equipped with “custom” devices - a gooseneck or a flexible hose with a diffuser.

The heating process occurs instantly, so there is no need to wait for a certain amount of hot water to accumulate. Electricity is only consumed when the device is operating.

Unlike its storage counterpart, a instantaneous water heater takes up minimal space. Usually it is fixed on the wall near the water point (sink or shower) in a vertical position

If we compare flow models with storage models, we can highlight the following advantages:

• space saving, compact size (important for rooms with limited free space);
• possibility of installation both near the tap (minimizing heat loss) and in separate room(applies to powerful devices);
• the amount of water consumed is not limited;
• interval power consumption (only during the active period);
• beautiful, laconic design;
• low cost.

The disadvantages include regular costs for paying for electricity: the more often the water heater is turned on (respectively, the larger the family), the higher the electricity bill.

Installation diagram of one device on two mixers. When choosing, you should focus on the power rating of the device. If it is not enough, the device can serve only one tap at a time (maximum – tap and shower)

Another disadvantage concerns the installation conditions. For water heaters with a power of 7-8 kW and above, a reliable three-phase electrical network, high-quality copper wiring and appropriate protection.

The presence of built-in furniture in the room makes it possible to hide the wall duct in one of the wall cabinets. Required condition– easy access to the housing, control unit and important components for maintenance

Why is an electric model better than a gas model?

In city apartments there is no need to choose between two types of devices, since they usually use electric, safer models.

The exception is apartments in which geysers were installed during the process of equipping the premises upon delivery of the house. This applies to “Khrushchev”, “Stalin” and some types of panel houses built in the 60-70s of the last century.

Diagram of the gas water heater. Prerequisite for its operation - water pressure is at least 0.25-0.33 atm (approximately 1.5-2 l/min), otherwise the heating elements will not turn on

In country houses, water is often heated using a powerful floor-standing boiler, but some people prefer to use a gas water heater out of habit.

Its use is appropriate when stove heating or in warm climates that do not require the installation of heating equipment.

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They are considered safer, although their operation is more expensive than using geysers. In addition, when heating with gas, exhaust hood and reliable ventilation are required, otherwise there will be a risk of poisoning carbon monoxide. Savings are considered a plus, since gas prices are lower than electricity.

In houses old building It is not possible to use a powerful electric device (above 3.5 kW), so you will have to make do with either a weak water heater or. Thus, if there is a choice, consider the state of electrical networks and ventilation, water pressure, and the cost of fuel (gas or electricity).

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Features of wall mounting

Instantaneous water heaters are installed in a place convenient for control, most often on the wall near the sink or shower. For attachment to concrete panels or brick walls use dowels; for drywall (not recommended) - special moth-type devices. The product should be positioned according to the instructions; it should not be rotated.

If you plan to install the water heating device near the water point, that is, in the bathroom or in a combined toilet, make sure that the degree of protection is not lower than IPX4

Connection to the electrical network must be made through, especially if the manufacturer does not provide a protective automatic shutdown function.

A three-core copper cable is pulled from a common grounding panel, then either a differential switch or a circuit breaker is installed.

Installation diagram for instantaneous water heater: 1 – pipe with cold water; 2 – tap (mixer); 3 – shut-off valves; 4 – set check valve+ filter; 5 – RCD; 6 – electrical panel

It is better to equip the supply pipes for a pressure water heater with ball valves - for ease of installation/dismantling. Remember that a free-flow device has only one pipe - for connecting cold water.

You can find out more about the rules in the article presented to your attention.

Rating of famous manufacturers

The main criteria by which products from well-known manufacturers are evaluated are quality, warranty period, standard functions, availability of additional options, variety of models.

The price of products can be ignored, since each manufacturer has lines of low, medium and high price categories.

Place #1 - Stiebel Eltron

The German company Stiebel Eltron produces impeccable equipment with a 3-year warranty. Known for the production of powerful pressure water heaters with a set additional functions. Easy installation and ease of operation, many convenient modes, temperature and pressure adjustment - outstanding qualities plus German reliability.

Model Stiebel Eltron DHB-E 13 SLi for wall mounting. Power – 13 kW, degree of protection IP 25, electronic control, emergency shutdown function

Place #2 - AEG

In Russia, a line of single-phase devices from the “mini” series, compact and economical, has become popular.

Instantaneous water heater AEG MTD 570 laconic design. Power 5.7 kW; productivity – 2.9 l/min; temperature is adjusted using hydraulic control

Place #3 - Electrolux

The Swedish company Electrolux, known for its variety of models in the mid-price segment.

Compact but quite powerful devices are cheaper than their German counterparts due to the use of less reliable materials in the design. Most of the products are made in China.

Flow-through model Electrolux NPX6 Aquatronic with a power of 5.7 kW with electronic-mechanical control. Equipped with an automatic on/off function, maximum heating temperature – +50 °C

Location #4 - Atmor

Israeli brand Atmor, which produces budget devices for home and garden. Compact devices with mechanical control have several operating modes, good protection against overheating.

Atmor Basic shower model. It has three operating modes - with a heating power of 2/3/5 kW, there is temperature control (maximum - +50 °C), indication, a mounting kit and a shower head with a flexible hose are included.

Place #5 - Timberk

Swedish company Timberk, which produces several series of inexpensive instantaneous water heaters. The Primalux and Watermaster lines are popular. The devices are not demanding on water pressure, have compact sizes and a modern design.

Model Timberk Primalux WHEL-7 with a power of 6.5 kW, designed for showers. Productivity – 4.5 l/min; water protection class – IPX4; has three power levels and a fine filter

The listed models are popular in Russia and are available in many online stores. Prices may vary depending on the exchange rate and the marketing concept of the selling company.

Review of the Timberk Watermaster series:

As you can see, the choice of instantaneous water heaters is quite wide. Before buying, decide on the power, consider the models different manufacturers, inquire about the availability of additional options and purchase the device that best suits your requirements.

If you have any questions, please contact your sales consultants and carefully study the instructions.

Today we will talk about instantaneous water heaters and give useful tips according to their choice.

Comfort of living comes first

It is now difficult to imagine a comfortable home without hot water. After all, it is one of the components of the amenities in the house.

The first hot water that people began to use were natural thermal springs. Then he began to use an open fire to heat water.

Later, heaters appeared, in which water was heated by burning solid fuel.

Nowadays, the most common are heaters that use gas and electricity as a source.

A feature of heaters with heat sources that provide water heating is the use of two types - storage type heaters and flow-through type heaters.

Electric water heaters are becoming increasingly popular at home.

Nowadays, many houses are built without connecting it to the gas main, and all the amenities in the house are provided by electricity.

Such water heaters are also relevant for home owners and summer cottages, to which it is impossible to conduct gas.

Well, it’s worth recalling that in many cities their residents only dream of a centralized supply of hot water and, probably, these dreams are unlikely to come true. Although hope dies last.

In general, where it is not possible to use gas to heat water or there is no centralized supply of hot water, electricity is used to heat cold water.

Types of electric water heaters

In both storage and instantaneous water heaters, the main element for heating water is the TEN. It’s just that they heat up differently.

In storage water heaters, water flows into a special container, inside of which the heating element is located.

Using an adjustable thermostat, the temperature to which the TEN should heat the water is set.

Having reached the desired temperature, the TEN turns off, but if the temperature drops slightly, it turns on again and brings the temperature to the desired value. This way it keeps the water constantly heated.

When the water is partially consumed, a new portion of cold water enters the container from the water supply system to the level, and it is heated again.

How to connect a storage water heater - diagrams.

Instantaneous water heaters do not have a water tank. Water entering the water heater passes through the supply pipe.

A housing with a heating element is attached to this pipe. Water passing through the pipe inside the housing heats up and goes through the outlet pipe to the consumer.

Advantages and disadvantages of instantaneous water heater

Instantaneous water heaters have a number of positive qualities:

• The lack of a water tank makes it very compact, and since this heater has a stylish outer casing, it fits perfectly into the interior;
• The instantaneous water heater provides hot water almost immediately after it is plugged into the network. Because of this, they are convenient to use in country houses and cottages;
• You can choose heaters of different power, capable of delivering hot water to one point or to several.

There is only one drawback of this type of water heater - in order to ensure rapid heating of the water flowing through it, it must have good power, which affects its energy consumption.

Types of instantaneous water heaters

Currently, two types of instantaneous water heaters are produced - non-pressure and pressure.

Non-pressure instantaneous water heaters can be connected to almost any source of cold water, but the main thing is that this source has a tap to shut off the water supply.

Below is the Electrolux SMARTFIX 3.5 S model.

For such a water heater to start working, it is enough to plug it into the network, set the water temperature and turn on the water supply at the tap.

The heater itself will subsequently be triggered by the flow of water, that is, if you turn off its supply, it will automatically turn off.

Because of this feature, these water heaters are unable to provide hot water several collection points.

But since they work only at one point, their power is relatively small - from 3 to 8 kW.

Pressure water heaters are included in the water supply system of the house. That is, the water in it is constantly under pressure.

But as long as all the taps in the house are turned off and no water is consumed, it does not work.

Below is the Stiebel Eltron DHF 13 C compact model.

As soon as one of the taps opens and a flow of water appears through the heater, it starts working.

Such a water heater is capable of operating at several points of intake. However, to ensure heating large quantity water it must have high power - up to 36 kW.

Schematic diagram installation of a pressure instantaneous water heater.

Design

Structurally, both of these types of instantaneous water heaters are similar. All their elements are enclosed in a housing.

On the one hand, there are two pipes - for supplying water to the heater and leaving it.

There is also wiring with a plug to connect it to the network. On the outer part of the housing there is a control unit that sets the temperature and operating mode of the heater.

Inside there are pipes through which water moves inside the water heater; these pipes pass through a copper flask with heating elements located in it, and where it is directly heated.

Also included in the design are fuses, a temperature stabilizer, a power regulator, a thermal cycling breaker and a flow regulator.

Non-pressure water heaters, since they can only provide one point of intake, may come with shower or sink attachments.

That is, it is enough to connect a pipeline with water to it, and on the other hand, connect the nozzle directly to the outlet pipe and the water heater is ready for use.

This allows you to use it as a portable one - install it in one place and use it, then transfer the loan to another.

Pressure ones are included in the water supply system.

In principle, it can be included in this system and use only when certain cases, for example, when hot water is turned off from the central water supply.

At the same time, they can provide hot water to the entire house.

Selecting a flow-through heater

When deciding to install a instantaneous water heater, you should decide on some features.

So, first you need to decide whether the electrical network at home can withstand such a load.

You also need to decide on the purpose of using the instantaneous water heater.

Below is a table, after studying which you can draw certain conclusions for yourself.

In old houses, where the wiring is not designed to withstand heavy loads, it will not be possible to install an instantaneous water heater. Although it is still possible to install a low-power water heater of 3 kW, even before purchasing it is better to check the network by connecting a consumer with the same power to it.

IN modern houses where an electric stove is used, there is no particular need to check the network; if it can withstand the stove, then it will also withstand the heater.

Based on this, the type of water heater is determined. If the network is weak, you should purchase only a non-pressure water heater.

Some owners, if several hot water supply points are needed, purchase several non-pressure heaters, and thereby solve this problem.

Determining the required power

This indicator is generally calculated by a certain formula, including the need to determine the water flow, the temperature of the water supplied to the heater and the outlet temperature.

However, it is possible to calculate the power of a water heater much easier.

It is enough to divide the power of the device in two, the resulting result is the volume of running water heated by it to 20-30 degrees. in a minute.

That is, a 20 kW water heater will heat 10 liters of water in a minute to 20-30 degrees. Based on this, it is already determined what the approximate water consumption will be and how much heater power is needed for this.

If you purchase a water heater that will provide several water intake points, then the power is determined by the point with the highest water consumption.

There is a possibility that water will be taken from several points simultaneously, then the resulting calculation result for the maximum flow rate from one point should be increased by one and a half times.

Other features when choosing

Before purchasing, you should immediately determine the location, especially for the pressure type.

It is best to place it as close to the electricity meter as possible.

The schematic diagram is shown below.

It is also advisable to install a circuit breaker in front of the outlet from which it will be powered, which allows you to protect the home network from unwanted overloads from the operation of the water heater, and the device itself from power surges.

The last criterion when choosing is the ease of its management.

Inexpensive options are equipped only with a power button and a manual temperature selector.

More expensive ones may already be equipped with a temperature display and touch controls. But this is a matter of taste and availability of finances.

For most, hot water shutdown situations are understandable.

In addition, the majority are indignant about turning off water precisely in the summer, the period when water is most needed in urban environments: playing sports, traveling to the country, or simply washing dishes is difficult.

However, this is the 21st century, and humanity has found a way out of this situation - searching for warm water.

The most economical fuel and, naturally, the method of obtaining hot water is gas and, accordingly, geyser. Is it true, this option Suitable for situations where there is a nearby gas main near your home.

In any case, the possibility of heating water is always available by installing a boiler that runs on liquid fuel, mainly diesel fuel. Although it is worth saying in advance that placing the unit will require not only free space, but also an entire room.

An electric water heater is also a good way to heat water. IN in this case electricity will cost a little more than gas, however, as history confirms, it works, and electricity is present in every home. Therefore, this will be the most suitable option– electric water heaters as convenient way heating water.

Operating principle

For those who are planning to purchase this equipment - an electric water heater, it is worth deciding on the basic principles of its operation. So, it’s a logical question what knowledge “dummies” will need.

The entire operating principle of this unit can be described in two words:

At the same time it is enough simple system has several variations due to which several types of devices can be distinguished, divided into classes according to the control method and power consumption.

First of all, we cannot ignore the option of a water heater with a power of 3.5 kW, which will ideally fit into a situation where there is no water, say, even, i.e. for summer use.

This is due to the temperature level provided by the device - water is not lower than 18 degrees; the second model is standard and already operates at a power of 5 kW, which is quite powerful and allows you to heat water even in winter.

It is worth noting the advanced options that have appeared on sale. These units have functionality that allows heating a mode with a power of 7 kW or more, however, the demands on the condition of the electrical wiring also increase. Considering that electrical appliances have high power, then they will require separate high-quality electrical wiring.

Do not forget about safety measures - it is worth grounding the device. As a rule, due to the connivance of the owners, the potential risk is reduced, and in most cases, the places where the device is located and used are not equipped with the appropriate quality of electrical wiring.

Therefore, even a device with a power of 5 kW, or even more, is not equipped with a plug and power cord for the safety of inattentive users when the heater is plugged into a regular outlet.

The best option would be if the fuses trip, but the worst would be melting of the insulation and a short circuit. It is necessary to calculate the home wiring for a current strength of 30 Amps.

In order to cope with this, you will need to find the corresponding inscription on the electric meter below the spinning numbers. With electric stoves installed at home, the total wiring is designed to be up to 8-9 watts. Anyway the best solution You will need to consult a professional electrician.

Previously, we already introduced you to the fact that there are several types of water heaters, where we can note devices of closed (pressure) and open (non-pressure) type, which have different operating principles.

1. Boiler closed type perfect for centralized system water supply. The heating container in this device is metal (enamelled steel, stainless steel, copper). To avoid damage to the container due to an increase in pressure when water expands during the heating process, an expansion tank is used in conjunction with the boiler. In steel tanks with increased pressure, corrosion is prevented by cathodic protection based on a sacrificial anode;
2. The open type of the device is able to supply only one water point due to the water supply fittings. The principle of operation of this type of fittings is reduced to shutting off the network water under pressure at the entrance to the container. This feature allows the container to be made from less durable materials, often plastic.

Closed type boilers can be used with special mixers, however open type with a safe group of safety, reverse and relief valves, and expansion tank cannot be used.

The very concept of “gravity-free” does not require necessarily filling the container and subsequently disconnecting it from the water supply source.

In order for water to be collected and hot water to flow, cold water should be fed under pressure into the container. In this case, the tank itself will always be full. If there is no pressure at the inlet, the water is not able to come out.

In cases of constant lack of supply, options for the device without thermal insulation are provided.

Which one is better to choose?

Having decided to purchase this device, you will have to pay attention to certain selection tips, which we will try to outline below with their advantages and disadvantages.

A flow heater will require:

• A wonderful option for the winter period, however, you will need to connect to a power supply of at least 12 kW;
• When solving a seasonal problem in the summer, it is worth turning to a device with 6-8 kW of power. This power is quite enough for a confident and comfortable shower.

As advantages flow heater it is worth noting:

• Compactness– small dimensions, which allows us to talk about its mobility;
• Economical(consume electricity only to maintain temperature). Also, as a rule, flow-through will cost the buyer less than storage. It is also worth noting an example of efficiency: usually a shower takes up to 10 minutes. An 8 kW “flow-through” device will consume about 1.33 kW for a given period of time. In turn, a 100-liter “storage” can fully warm up in 4 hours. Considering simple arithmetic calculations: in 4 hours 1.5 kW is 6 kW of electricity consumption. Extremely clear.
not limited by the amount of hot water drawn. The heating option is limited by the container’s own volume. Although, if such electrical power is not possible, then there is no alternative, as such, to a storage device.

What's inside?

• Inside the storage version of the water heater there is an internal flask, thermal insulation (the thickness of which determines the reduction in electricity consumption), and heating elements.
• The flask must be made of steel with an anti-corrosion coating.
• When choosing a small volume water heater, it is necessary that they contain a copper inner bulb.
• Regarding stainless steel, it is worth noting only its unsuitability for production: poor weldability of the material will lead to leakage of seams or corrosion at the welding site.

What should you pay attention to when purchasing?

1. When in a instantaneous water heater the heater is replaced with a spiral - open heating element, then if there is air lock it will easily burn in water.
2. Without safety valve supplied with the storage water heater, excess water will not be discharged, which will lead to rapid decommissioning.
3. If there is no anti-corrosion anode in the storage model or its volume is too small, then after a certain time the flask will begin to corrode.
4. A water heater without IP 24/25 protection will be unprotected from moisture, water jets, splashes, and therefore its installation in the bathroom is not safe.
5. In the case of a horizontal water heater, it is impossible to ensure that hot and cold water do not mix.

During the selection process, you should pay attention to the following brands and models of heaters.

Among instantaneous water heater models household type affordable and easy to use, the choice is quite extensive.

In addition, the bulk of the devices presented in stores are affordable in terms of cost, which starts from 1,300 rubles (say, for the Timberk WHEL-3 OS option) and up to 32 thousand -36 thousand rubles. (AEG, Stiebel Eltron).

Also in the store you can find models from manufacturers Thermex, Stiebel Eltron, Electrolux, AEG, Bosch, Atmor, Polaris and others. Cumulative options are more popular, so their variety on the shelves is wider:

AEG, Gorenje, Ariston, Thermex, Timberk, Electrolux, Haier, Stiebel Eltron, Atmor, Bosch, Polaris. The price level for these devices starts from 2,500 rubles (Haier ES6V-Q1 for 6-liters) and up to 130 thousand rubles. (Stiebel Eltron, AEG, Austria Email with volumes of 150-300 l).