Dark mode
Catalog   /   Climate, Heating, Water Heating   /   Water Supply & Pumps   /  Water Heaters
Water Heaters 

Articles, reviews, useful tips

All materials
Rating water heaters (march)
The popularity rating of water heaters is based on comprehensive statistics on the interest shown by the Internet audience
From A+++ to G: energy efficiency classes for household appliances
We understand the intricacies of symbols and pictograms on labels with household appliances
How to get through the winter: autonomous house
Autonomous sources of electricity, heat and hot water to comfortably get through the winter
What is legionella and how to protect your water heater from it
Clean boiler without legionella: how to prevent bacterial infection in your own bathroom
Energy saving electric boiler. How to choose?
How to choose a boiler to spend less on domestic water heating

Water Heaters: specifications, types


In heaters, in addition to the classic, familiar to all boilers ( storage heaters) and gas water heaters, you can find flow-through wall-mounted, flow-through taps and boiling systems.

Flowing. Flowing water heaters are called water heaters that do not have built-in tanks — the water in such devices is heated directly in the process of passing through...the heater. Compared to accumulative, such devices are more compact (due to the lack of a reservoir) and fast-acting — heated water comes out of them immediately. In addition, they are considered more energy efficient: during operation, only the water that is currently being used is heated, there is no need to waste energy on maintaining the temperature in the tank. At the same time, note that for efficient heating of running water at high pressure, a rather high power is required. For example, a shower will require an instantaneous electric heater with a power of at least 8 kW — and such power requires a special connection format, besides, weak wiring may simply not withstand the load. There are also less powerful instantaneous water heaters, however, their efficiency, respectively, will be lower. However, gas heaters are deprived of these shortcomings (see "Source of Energy") — in general, it is not difficult to provide the necessary power in them.

— Cumulative. Water heaters equipped with their own water tank; cold water is drawn into this tank, heated and already from the tank is supplied outside. It takes some time to heat up and the hot water in the tank is limited. Therefore, storage heaters are not designed for continuous operation, and when using such a device, you need to be careful not to use up all the hot water ahead of time. In addition, storage heaters are noticeably heavier and larger than flow heaters (and the larger the water supply, the larger and more expensive the device), and their energy consumption is generally somewhat higher, because. stored water cools down over time, and it must be regularly heated to a predetermined temperature. However, such devices have one key advantage: they do not require high power, they do not create such loads on the power grid as flow-through ones, and many fairly large storage boilers work without problems from a regular household outlet. In addition, the pressure of water from such a device can be almost any (whereas in flow models this moment, again, is directly limited by power).

— Boiling system. This type of water heater is a set of a tap, a small storage tank for water and additional filters. The installation of the device is very similar to reverse osmosis filters (with the exception of the mandatory presence of power supply) and flow heaters on the tap (see below) — only the tap is located in the visible area, the rest of the “organs” of the system are hidden from view. A key feature of boiling systems, which is why they got such a name, is the ability to heat water up to 100 °C, thereby several liters of boiling water always flow from the tap without waiting. Manufacturers position such systems as an alternative to kettles (naturally, if there is enough good quality water in the tap). It is worth considering that such sets exist in a truncated version (without a water tank), in which case they are in our catalog in the taps section.

— Flow to the tap. Flow heaters in the form of water taps. Devices of a similar form factor are installed instead of a standard tap directly on a kitchen sink, washbasin, etc. One of the advantages of their design is the minimum of additional equipment at the draw-off point: only one device instead of a separate tap and water heater.

Energy source

Gas. In such a device, it is easy to provide a high heating power — even in the most modest devices, it is calculated in kilowatts. However, gas models are difficult to install, since they require a gas line and a chimney gasket to remove combustion products. At the same time, the mentioned high power is relevant mainly for gas water heaters (instantaneous water heaters), and most gas models belong to this type. However, there...are also storage gas water heaters.

Electric. Electric water heaters are versatile and easy to install — unlike gas, and they do not need a chimney. On the other hand, even for relatively low-power models (up to 5 kW), high-quality electrical wiring is needed, and more powerful heaters require a separate connection to the electrical panel or even a three-phase power supply. In addition, electric heaters are often considered more expensive to operate than gas heaters. This option is popular mainly among accumulative models (see "Type").

Indirect. Such water heaters do not have their own heating element (electric or gas). Its role is played by a heat exchanger, through which a coolant moves, heated by an external source (most often a heating boiler) — due to this, the water is heated. Indirect heaters are made only accumulative (see "Type") — this is due to the design features. They cannot be installed autonomously — an external heating source is required; the installation process itself can be quite complicated. The main advantage of this option is that it does not require a separate supply of electricity or gas to heat water. In addition, an indirect heater allows more efficient use of heat from a boiler or other heater: the energy that could “fly out into the pipe” is instead used to heat water.

— Combined. Such water heaters are a kind of hybrid between indirect and electric. The main heating of the water in them is provided by a heat exchanger operating at the expense of an external source of heating (for example, a heating boiler) or a built-in heat pump. And an electric heating element (usually, a heating element — see "Heater type") serves for additional heating. Combined heaters provide a higher temperature than conventional indirect heaters and are more economical than electric ones. Their main disadvantage is their rather high cost.

Solar heating

Possibility of operation of a water heater from a solar collector. To be more precise, we are talking about the possibility of connecting an indirect or combined model heat exchanger (see "Type") to a solar collector. Such heating sources have their own characteristics, and for use with them it is worth choosing water heaters in which compatibility is directly stated. At the same time, only one of several water heater heat exchangers can be responsible for working with solar energy.


Regular way to install a water heater.

The choice for this parameter depends primarily on how much free space is available for installing the device and what shape this space has. Therefore, when there is a lot of space (for example, the user has an entire wall in the boiler room of a private house at his disposal), this parameter can be ignored. But in cramped conditions, each installation method will have its own nuances.

Vertical. Vertica...l arrangement devices, elongated in height. This option is well suited for narrow cramped spaces — for example, a bathroom in a small city apartment.

Horizontal. The horizontal layout is less suitable for tight spaces than the vertical one, but in some conditions it may be optimal — for example, if the place under the device looks like a low horizontal niche. Also note that many instantaneous water heaters are produced in this design (see "Type") — they do not take up much space, and horizontal orientation is considered optimal for such devices for a number of reasons.

Outdoor. Floor mount models (as opposed to all of the wall mount options described above). The main advantage of such an installation is simplicity: there is no need to drill walls and prepare other special fasteners, it is enough to have free space on the floor. In addition, weight restrictions are not so critical for floor water heaters, and this method can be used even for the most powerful, capacious and, accordingly, large models. On the other hand, just free space on the floor is not always available, and this installation method is not suitable for cramped conditions.

— Universal (suspended). Devices that can be placed in any position — both horizontal and vertical (see above for details). The advantage of this option is obvious: the user can choose the installation method of his choice, depending on the situation.

Tank volume

The volume of the tank installed in the storage water heater (see "Type"). This is one of the key parameters for such devices. On the one hand, a large tank allows you to keep a large supply of water and reduces the risk that it will run out at the most inopportune moment; this is especially important when water consumption is high, such as in a large family. On the other hand, a volumetric tank correspondingly increases the size, weight and cost of the entire device, requires reliable fastening...s (when installed on a wall), and more energy is spent on heating and maintaining the temperature of the water in it. Accordingly, when choosing, it is worth not chasing the maximum volume, but proceeding from the actual water consumption and from this point of view determine the optimal capacity of the tank.

There are special tables and formulas that allow you to calculate the optimal volume of the tank depending on the format of use (washbasin, shower, kitchen sink ...), the temperature of the water used and other parameters. These data can be found in special sources. Here we note that the smallest storage water heaters can hold only 5 liters; such devices are designed for washing, washing dishes for 1 – 2 people and other tasks that do not require a lot of water. The average indicator is considered to be a volume of 80 – 100 liters, such a tank is quite enough for an apartment in which 3 – 4 people live. And in the most "large-caliber" models, the volume is already calculated in cubic metres; such heaters are designed, for example, for hotel buildings, showers in sports complexes and swimming pools, and other similar places where a lot of hot water is required.

2 tanks

The presence of 2 separate tanks for water in the storage water heater; usually, the total volume is divided equally between these tanks.

This design is noticeably more complex and expensive than the traditional 1-tank arrangement, but offers several advantages. Firstly, the containers can be heated in turn, which significantly speeds up the process: after all, in order for hot water to be used, it is enough to warm up only half of the total volume to...operating temperature. Secondly, with this format of work, power consumption and the load on the power grid are reduced; and if at a certain moment the user does not need a lot of water, then the energy consumption turns out to be small (again, due to the fact that the entire volume does not need to be heated). Thirdly, compared to traditional models of the same volume, such boilers are thinner, which can simplify installation (the price for this advantage is an increase in width, but this moment is not so often critical). Fourth, this arrangement improves thermal insulation and reduces heat loss.
fromup to
Water heater type
Heater element type
Tank shape
Safety systems
Power consumption
Max. water temperature
Tank lining
More features
Advanced filters
Catalog water Heaters 2023 - new products, best sales, buy water Heaters.