Comparison Atlantic Steatite Cube WI-FI ES-VM 100 S4C2 WD vs Drazice OKHE 100

This parameter characterizes the efficiency of electricity consumption by the water heater. Classes are indicated by latin letters from A to G (A, B, C, D), where A is the most energy efficient device.

Electrical power consumed by the heater during operation.

This parameter is of key importance for electric models (see "Energy source"). In them, the power consumption corresponds to the power of the heating element and, accordingly, the heat output of the entire device. The overall efficiency and flow rate of the water heater directly depend on the useful power. Accordingly, high-flow rate models inevitably have high consumption. At the same time, we note that the heating power is selected by the designers in such a way as to guarantee the necessary flow rate and water temperature. So when choosing a device according to flow rate, you need to look primarily at flow rate and temperature. Power must be taken into account when connecting: for example, if a 220 V model (see "Power source") consumes more than 3.5 kW, it, as a rule, cannot be plugged into a regular outlet — connection is required according to special rules. And the most productive and high-powered models — 10 kW or more — are connected only to three-phase mains.

The power consumption has a similar value for combined boilers — adjusted for the fact that in them the electric heater is an additional source of heat. For gas and indirect models, this parameter describes the power consumption of control circuits and other auxiliary structural elements; this power consumption is usually very small — on the order of several tens of watts, less often up to 1.5 kW.

The highest water temperature provided by the device. The standard temperature of hot water in the water supply is 60 °C, and this value is actually the minimum for modern water heaters: models with more modest rates (usually from 40 °C) are extremely rare. But higher values can be found much more often: for example, water heaters of 75 °C and 80 °C are very popular, and in the most powerful models in this regard, the temperature can reach 95 °C and even higher.

On the one hand, strong heating requires appropriate power (which is especially noticeable in the case of instant electric heaters). On the other hand, the higher the temperature of hot water, the less it is needed for a comfortable outlet temperature, after mixing with cold water; this reduces the consumption of heated water, which is especially important for storage boilers. In addition, many models have thermostats (see "Features").

Also, note that heating to operating values may involve different ΔT (degree of temperature change) — depending on the initial temperature of the cold water. The actual performance of the heater directly depends on ΔT; this moment is described in more detail below, in the paragraphs devoted to performance at different ΔT.

Time to heat the storage tank (see "Type"), filled with cold water, to operating temperature.

It is worth remembering that this characteristic is not 100% accurate. Manufacturers usually indicate the heating time for certain conditions: a filled tank, maximum heating intensity, and temperature rise (∆T) by a certain number of degrees. In practice, the heating time may differ, both one way and the other. For example, if the heating time for the device is 20 minutes at ∆T = 50 °C, then when the water is heated from 15 °C to 60 °C, the time will be shorter (∆T = 45 °C). Nevertheless, this indicator allows us to evaluate the overall flow rate of the boiler, and with equal ∆T and volumes, different models can be compared in terms of heating time.

Among the functions of the water heater there are thermostat, water flow regulator, Smart (auto mode), programmer, display and control via the Internet. More about each of them

— Thermostat. A device that allows you to control the temperature of the water at the outlet of the heater. In storage models (see "Type"), the thermostat sets the maximum temperature for heating water in the tank; in instant devices, this function is carried out by changing the intensity of heating.

— Automatic water flow regulator. It is used in instant water heaters. Since the water in such devices heats up in the process of its movement through the heater, the higher the speed of water movement (the greater the pressure), the lower the heating temperature, and if the pressure is too high, the power of the device may simply not be enough for effective heating. The use of an automatic water flow regulator avoids this — this system regulates the speed of water movement through the heater, limiting it if necessary.

— Smart (auto mode). A special “smart” mode in which the boiler is controlled (primarily the intensity of heating) automatically. Specific features of this mode may vary depending on the model. However, the following format of operation is m...ost common: during the first week of use, the device remembers at what time of the day the hot water was used, and then the heater’s operating mode adjusts to this data. Thus, the water heater provides the user with hot water at the right time and, at the same time, does not waste energy on heating during hours when heating is not needed.

— Programmer. The presence of a programmable thermostat — a device that allows not only to maintain the temperature but also to programme the operation of the device for a certain period. The simplest programmers work like a timer, turning on at the right time (vacation or holiday mode, when the device is not active for several days, and when the family returns to the house, it will turn on and heat the water). More advanced ones allow you to set the mode of operation for individual days. Either way, this feature provides added convenience and eliminates the need to constantly adjust the operation of the device manually. On the other hand, the presence of a programmer affects the cost.

— Display. Usually, a simple LCD screen with a few characters is used as a display. However, even such equipment significantly increases the convenience and information content of management. Various service data can be shown on the display — from the temperature of the water in the tank to messages about malfunctions and failures. This feature slightly increases the cost of the device, but compared to the total cost of the heater, this moment is usually insignificant.

— Control via the Internet. The specific nuances of such control may vary: for example, some models use a special application installed on a smartphone or tablet, while others can work through a regular browser from any computer. However, this function allows you to control the heater from almost anywhere in the world — provided that there is access to the Internet. In addition, with this control, the user can also monitor the status of the device and receive various notifications (on and off, about the temperature of the water in the tank, about various problems, etc.).

- Mechanical. Manual control using rotary knobs and mechanical buttons. Models with mechanical controls are inexpensive, but the control capabilities themselves are quite limited and, as a rule, include only basic functions.

- Electronic. This control is carried out using an electronic unit. Electronically controlled heaters, as a rule, have a wider range of functions than their “mechanical” counterparts; they can be programmed and equipped with a display to indicate various parameters. On the other hand, with all other characteristics being equal, such heaters are much more expensive.

The warranty period declared by the manufacturer for the storage water heater tank (see “Type”).

This parameter is important for the reasons of maintenance terms. The tank is the most complex element: other parts of the water heater are relatively easy to repair and change, and if there is a problem with the tank, it is often easier to replace the entire boiler. In the most advanced models, the warranty on the tank can be 10 years or more.

The weight of the device, excluding the water collected (passing) into it.