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8 Tips on How to Choose an Electric Water Heater (Boiler) for a Private House and Apartment

For some reason, utilities are sure that in summer people do not really need hot water, so they strive to turn off its supply for a long time in connection with repair work or for some other reason. If you don't want to heat the water on the stove and don't want to wash in a basin, it's time to think about buying a boiler. Those who are not connected to a centralized hot water supply system cannot do without it. The variety of boilers is decent, but often it is the wide range that makes you stupid. Let's try to figure out how to choose an electric water heater for a house and an apartment, and we will deal with all the nuances of the right purchase.


Water heaters can be electric or gas. The latter are popularly called columns and are used less and less because of the increased danger. Electric water heaters are called boilers. They are well known to many of us, they are distinguished by quiet operation, ease of use, durability and safety, if, of course, and the choice was made correctly.

By the type of heating, electric water heaters are:

  • flowing;
  • accumulative.

Instantaneous electric water heaters

Boilers of this type are compact in size and allow you to heat water instantly. Tap water, in contact with the heating element, is heated and enters the tap already hot, i.e. there is no mixing process with cold water. Water heating occurs instantly, since the power of the heating element is decent. Boilers of this type are often used in apartments, where there are frequent interruptions in the centralized supply of hot water. They do an excellent job of heating water for one water intake point. If you turn on hot water in two places at the same time, it may not have time to warm up - it all depends on the power.

The power of instantaneous water heaters ranges from 3 to 27 kW. In an apartment with a single-phase voltage of 220 V, you cannot use an 8 kW boiler. A flow-through boiler with a capacity of 3-8 kW heats 2-6 liters of water per minute, which is not so little - this will be enough for the household and hygienic needs of a small family.

For a private house with a three-phase voltage of 380 V, you can take a more powerful boiler. Then there will definitely not be problems with a shortage of hot water.

Advantages of instantaneous boilers:

  • compactness;
  • fast heating of water;
  • Water is heated only when it is needed. He turned on the tap - warm water flows, turned off the tap - the water is not heated, which means that electricity is not consumed, which is the competitive advantage over storage boilers;
  • Hot water will not run out suddenly. In storage boilers, if the hot water supply is used up, you will have to wait a long time for heating.


  • high power turns sideways if the wiring in the house is not very good (for Khrushchev’s and other old houses this is a serious problem), and even with frequent use of such a boiler, electricity bills will not please you. The storage boiler is more economical in this regard;
  • water in a flow-through boiler can overheat, as it heats up very quickly, and does not mix with cold water. In this case, the boiler will first drain hot water, then warm, and then cold water will flow from the tap, and only then normal operation will resume. That is why it is very important that the boiler has a heating limiter.

Instantaneous water heaters can be of two types:

  • free-flow. Heats water only for one point of water intake, therefore it must be located in the immediate vicinity of it. For city apartments, this is not the most convenient option, but such a boiler is ideal for summer cottages ;
  • pressure head. Such a water heater is built into a water riser, so the device allows you to heat water for several points of water at once.

Sometimes it is even possible to find a water heater-tap on sale, which can be considered the most simplified version of a non-pressure boiler.

Storage electric water heaters

In any case, the storage boiler will be larger than the flow boiler, since it is equipped with a tank in which the already heated water is heated and stored. When someone turns on the faucet, hot water from the boiler mixes with cold water and flows through a mixer or shower head. As the water is consumed or cools down, the appliance turns on heating again. The volume of the tank ranges from a modest 10-30 liters to 150-200 liters. Such a water heater is installed on the wall or on the floor - it all depends on the size of the tank.

How much storage boiler volume is needed? It all depends on the needs of the family for hot water. To wash, on average, one person spends 40-50 liters of water, but keep in mind that hot water from a water heater is mixed with cold tap water. Taking a shower takes less water than taking a bath. When choosing the volume of the boiler, you can focus on the following data:

  • A boiler with a volume of 50-80 liters is enough for a small family of up to 3 people to wash the dishes and take a dip in the shower. In principle, you can take a bath if you heat the water in the boiler to the maximum;
  • 80-100 liters - option for a family of 4 people. Such a unit is not much more expensive than a 50-liter boiler, but a larger tank will heat up longer;
  • 100-150 l - boiler for a large family of 6 people. There is enough water for several washbasins, for a shower, and for filling a bath;
  • boilers with a volume of more than 150 liters are used, as a rule, in private houses, are installed on the floor and consume a decent amount of electricity.

It is important not to miscalculate with volume. If it turns out to be insufficient, there will be constant inconveniences, and if it is excessive, then you will have to overpay and wait too long for heating.

Among the main advantages of storage boilers, we note:

  • profitability. An average boiler, suitable for a city apartment, consumes 1.5-3 kW of electricity during heating and can be connected to a regular 220 V network;
  • one boiler, even not of the largest volume, will be enough to fully supply all water intake points in the apartment with hot water;
  • durability.

The storage boiler immediately heats the entire volume of water in the tank, so the larger its capacity, the longer it will take to wait (a 30-liter tank will heat up in 1-1.5 hours, and a 120-liter tank will heat up to 4 hours). Besides, for huge water heaters it is still necessary to find a suitable place. Usually the boiler is located in the bathroom or toilet, so do not forget to take a tape measure before buying and measure how large the equipment can fit in the bathroom, so as not to interfere with free movement. Small-sized water heaters are produced not only in the usual vertical, but also in horizontal form. Some manufacturers produce built-in models that can be placed in a cabinet under the sink.

Combined water heaters

This type of device combines the advantages of storage and instantaneous boilers. Combined water heaters, small in size, have a weight of no more than 6 kg, are equipped with a tank with a volume of 10-30 liters and can operate in two modes. The choice of such models is not very wide.


Heating elements are responsible for heating in boilers, spiral heating elements are less often used (they are more powerful, but if something happens, they are more difficult to repair).

Heating elements can be of two types:

  • "Wet";
  • "Dry".

It is easy to understand who is who by the name. "Wet" heating element is a copper heating element that is immersed in water and works like a boiler. Such heating elements are typical for many storage and almost all flow-through boilers. These are cheap devices, but due to the direct contact of the heating element with water, scale quickly forms on it, which has high thermal insulation properties, due to which the ability to heat water from the heating element decreases. Sometimes, you might even find rotten egg smell in house and this can be because of the chemical reactions in the water heater. A plumber can help you fix this.You will have to constantly increase the temperature, and this will affect the life of the boiler. It is noteworthy that the higher the heating temperature, the faster the scale forms. In addition, the "wet" heating element is subject to electrochemical corrosion. If a water filter is installed in the apartment, then, in principle, you can take a boiler of this type, it is cheaper. When working with hard water, prepare to clean the heating element every 3-4 months.

"Dry" (statin) heating element is protected by a special flask and does not come into contact with water, so scale cannot form here. The heat transfer of such a heating element is much higher, the service life is also much higher, but a boiler with a similar heating element will cost 1.5-2 times more.

Boilers Atlantic
A good example of a water heater with a "dry" heating element is the French Atlantic. Atlantic factories are located all over the world. Except for China - that's why Atlantic is often called the most "non-Chinese" water heaters. Boilers Atlantic are equipped with a self-developed steatite heating element with a service life of up to 20 years. This is ten times longer than that of conventional inexpensive "wet" heating elements.

Due to the coating of the tank with branded enamel with titanium dioxide and a magnesium anode, scum practically does not settle in Atlantic boilers and rust does not appear. Therefore, Atlantic is also the quietest, most economical and reliable water heaters of all that are sold in Russia.

Atlantic works with all types of water and are provided with a maximum tank warranty of 7-8 years. And the Atlantic does not need to be serviced annually, like most ordinary Chinese manufacturers. And once every 2-3 years.

Storage water heaters can be equipped with one or two heating elements. The second heating element is received by all large volume boilers, as well as models with a fast heating function.


The inner surface of the storage tank constantly interacts with water, therefore, it must be as resistant to corrosion as possible. To date, water heaters are on sale in which the inner surface of the tank is made of the following materials:

  • stainless steel;
  • enamel coating;
  • glass ceramics;
  • titanium sputtering;
  • plastic cover.

Boilers, in which the tank has a plastic inner lining, are the cheapest, but their reliability is also questionable. Stainless steel tanks proved to be the best. Manufacturers give them a 10-year warranty, and some carry out additional passivation, increasing the warranty period to 12 years. Such tanks are preferable in terms of durability and reliability, but they are also expensive. The most expensive boilers receive a titanium coating, which extends the service life by several more years.

Enamel-coated tanks are not much inferior to their stainless steel counterparts. Thanks to the addition of special additives to the enamel composition, it receives the same coefficients of expansion as the steel from which the tank itself is made, therefore, such a coating will not crack when heated. The enamel coating is being improved day by day. Today you can find water heaters in which the enamel is coated with silver ions. Due to this, antibacterial and anticorrosive properties are increased.

Some experts note that plastic, enamel and glass ceramics can receive mechanical damage from temperature extremes and when interacting with solid particles found in tap water. Nevertheless, enamel and glass-ceramic coating is not the worst option for a boiler, although it is incomparable with stainless steel.

On the other hand, no matter how strong the inner lining of the tank, the weak points are the same in all cases. These are the welds that start to rust first. To prevent corrosion of the tank and "wet" heating element, anode protection is provided in the design of all modern boilers. To do this, use a magnesium, titanium or aluminum anode, the tank acts as a cathode. The anode can be called a consumable. It is better to change it every few years, while cleaning the heating element and flushing the tank in parallel.

Remember that a quality boiler made according to all the rules cannot be cheap. The absence of a guarantee or its very short period should also indicate that the manufacturer, to put it mildly, is not sure about the quality of his products and wants to quickly relieve himself of responsibility for it.


When deciding which boiler to choose, you can get so carried away by studying the data on power, volume and material that you forget about much more obvious things. It's about the shape of the case. There are few options here, the case may be:

  • round;
  • rectangular.

Boilers with a round barrel-shaped body, as a rule, are cheaper (because they are easier to manufacture), but take up more space. This is the most popular option. Devices with a rectangular tank will save space, since they can be installed in a corner, niche , on the edge of a wall, or even completely hidden in a cabinet . Moreover, such models, due to their shape, are supplied with a thicker layer of thermal insulation. There are also so-called slim models on sale, in which the diameter or one of the sides is smaller than in standard devices. It is very important to decide before buying exactly where the boiler will be located, and how much space is available for its installation.

As for the color, there are few options. The most popular and safe option is a white body. Also in demand are gray and silver models.


Depending on the installation features, boilers can be:

  • vertical;
  • horizontal;
  • universal.

Vertical and horizontal boilers differ in design features and location of the heating element, which can be attached to the bottom plate or the side surface of the tank. It is not recommended to mount vertical water heaters horizontally - their performance may decrease, and vice versa.

If there is not enough space in the bathroom , then it is better to stay on a horizontal model. Such a boiler is mounted under the very ceiling, takes up a minimum of space and is not striking. On the other hand, a horizontal boiler is slightly more expensive, more difficult to install and maintain.

Universal boilers captivate by the fact that they can be mounted as you like without losing functionality and performance.


You can set the required operating parameters and control the water heating in the boiler in one of two ways:

  • mechanical control. The easiest, cheapest and most practical option. The degree of water heating is set with a rotary lever located on the bottom of the boiler. On the boiler itself there is a small window with an arrow, with which you can control the current temperature of the water in the tank. Everything is extremely simple - there is practically nothing to break here. The downside is that it is difficult to accurately adjust the water temperature, as, in principle, and determine the current degree of heating;
  • electronic control. Represented by a display and physical or touch buttons. The user gets the opportunity not only to set the desired heating temperature with an accuracy of a degree, but also to memorize heating modes, carry out diagnostics, start an economy mode, etc. Such boilers are more expensive and, moreover, are sensitive to voltage drops in the network.


When choosing an electric water heater, it does not hurt to pay attention to its configuration and additional options:

  • for a storage boiler, a layer of thermal insulation is important. It should be at least 35 mm so that the water in the tank stays warm for a long time, saving the family budget. Foamed polyurethane is an order of magnitude superior to foam and will be the preferred material;
  • the overheating protection function is an important part of your safety. If the boiler will be operated in the country, then it is worth looking at a model with a frost prevention mode;
  • the timer will allow heating at night when electricity is cheaper. Such models are not much more expensive than ordinary ones and will be useful for those who have a two-tariff meter installed ;
  • each boiler has a certain degree of protection against moisture. If the device will be used in a bathroom, it is better to take a model with IP44, in other cases the minimum level of protection IP23 will be sufficient;
  • as a rule, normal manufacturers equip their boilers with a power cable and a blow-off valve. The latter is installed at the point where the water pipe enters the boiler and prevents overpressure. Also, the presence of factory brackets will not hurt, thanks to which the boiler will be mounted;
  • it is worth taking care of the presence of a bushing for isolating stray currents.

Most likely, you will have to buy water pipes, valves, connecting fittings, and sometimes fasteners. If the water in the region is oversaturated with salts, it will not hurt to install a filter.

The installation of the boiler should be carried out by a professional who is able to accurately follow the instructions and the requirements specified in it. Otherwise, there may be problems with the warranty repair of the equipment. It is important to ensure proper grounding and check whether the pressure in the water supply system corresponds to the operating pressure of the boiler: if cold water is supplied with a higher pressure than it should be, you will have to install a pressure reducer. Finally, note that there must be sufficient free space in front of the boiler.


The topic of water heater manufacturers requires separate consideration . Now we will highlight only the largest companies that are engaged in the production of boilers:

  • ARISTON, Italy - reliable technology with low energy consumption. Most models receive an accelerated heating function. The manufacturer's boilers are quite easy to install and durable, differ in excellent price / functionality ratio;
  • Gorenje , Slovenia - boilers widespread throughout the world, which have proven themselves to be unpretentious, wide variety and reasonable prices. The company constantly introduces innovative technologies and improves equipment safety. There are models with horizontal installation;
  • Thermax, Italy - a large company with offices around the world, produces boilers of various capacities and sizes. The tanks are coated with stainless steel with bio-glass porcelain, a multi-stage safety system and a magnesium anode. The assortment includes slim models;
  • Bosch, Germany - the giant also produces water heaters. The assortment is wide, the quality is German, the prices are appropriate, but it is better to pay once and not know any problems for the next few years;
  • Electrolux, Sweden is a world-renowned company, constantly improving products, introducing innovations. They take a responsible approach to the design of equipment, as well as to safety. The assortment is sufficient, many models receive "dry" heating elements;
  • AEG, Germany - produces flow and storage type boilers of the premium level. Flow-through ones have a capacity of 3.5 to 27 kW, storage ones differ in volume from 5 to 400 liters;
  • ZANUSSI, Italy - reliable and durable boilers, there are vertical and horizontal models, all receive a magnesium anode and a protective shutdown function. In terms of safety and efficiency, this is an excellent solution, but it is difficult to call the company's boilers cheap;
  • Siebel Elton, Germany - expensive instantaneous and storage boilers, which are distinguished by their pleasant design, functionality and practicality;
  • ELDOM, Bulgaria - very good vertical and horizontal boilers. The range is wide in terms of volume, the prices are affordable, the tank coating in most models is enameled;
  • among the domestic companies, one can note Real and Oriol, which produce good boilers and give them a long warranty.
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