In one of the previous publications, we have already considered the pros and cons of electric storage and storage water heaters. flow type.
As you now know, DHW cylinders require quite a lot of space for their installation. After all, the minimum recommended volume of such a heater for a family of three with a small child is at least 80 liters.
Instantaneous water heaters, unlike their capacitive counterparts, have a very small size and the availability of free space is not at all critical for them.
Let's consider in this article what kind of flow-through electric water heaters are, what is their power, principle of operation, and we will analyze the basic recommendations for choosing a flow-through type heater.
Pros and cons of instantaneous electric water heaters
The undoubted advantages of instantaneous water heaters include:
- compactness;
- placement in close proximity to the tapping point, which reduces heat loss hot water;
- Unlike a capacitive heater, in a flow heater, electricity is consumed only immediately at the time of drawing. In a storage heater, electricity is also consumed to maintain the temperature of hot water in the tank;
- the amount of hot water is not limited by the volume of the tank, like in the storage heater;
- more aesthetic appearance;
- the presence of heating control systems depending on the water flow rate, as well as protection against pressure surges and water boiling when the flow rate decreases.
As you can see, the advantages are quite significant. So, living in a small apartment, where every square centimeter is worth its weight in gold, it is not so easy to choose a place to install a 100-liter barrel, which is a capacitive heater.
And fix the small box of the flow heater next to kitchen sink or in the bathroom won't be a problem.
A noticeable disadvantage of instantaneous water heaters can be considered a very large consumption electrical power, which actually allows you to heat water "on the fly". Due to the high electrical load, the instantaneous water heater must be connected with a special cable from electrical panel on the staircase... Such a heater cannot be simply plugged into any outlet.
It is this disadvantage that most often holds back many buyers who prefer to sacrifice living space in their apartment to install a storage-type heater.
Instantaneous water heater device
An instantaneous water heater consists of a body, heating elements, usually consisting of several stages, a temperature controller, a flow sensor and a safety automation.
The flow-through water heater diagram is shown in the figure below:
The numbers in the figure indicate:
1 - supply cold water; 2 - hot water outlet; 3 - electronic control unit; four - heating elements; 5 - remote control remote control(optional).
Water entering the water heater from the water supply first passes through the control unit, which, depending on the water flow, turns on the required number of heating elements or turns them off completely in the absence of water in the heater.
Using the control knobs (or the remote control for more advanced models), you can set the required water temperature at the outlet of the water heater.
Characteristics of instantaneous water heaters
All flow-through water heaters can be divided into two large groups - pressure, pressure-operated, and non-pressure.
Pressure heaters can serve several draw-off points at the same time, the main thing is that the necessary pressure is provided for this.
Non-pressure heaters, as a rule, are installed directly on the water tap or have their own watering can in the kit. Such a heater can provide hot water only one draw-off point.
According to the type of heater operation control, all devices are divided into heaters with hydraulic and electronic control.
Hydraulically controlled heaters have more simple design and the heating element either does not have power regulation or has step switching capability.
Electronic control controls heating much more flexibly depending on the amount of water flowing through the heater and the set temperature.
How to choose the performance of an instantaneous water heater?
To choose an instantaneous water heater, you will need to determine its optimal performance, which is expressed in liters per minute and is determined by the formula:
V = 14.3 W / (t2 - t1),
where V is the volume of heated water, l / min;
W is the power of the water heater, kW;
t2 is the temperature of the water leaving the heater, ° С;
t1 - water temperature at the heater inlet, ° С.
The temperature in winter can be as low as 5 ° С, and in summer it can reach 10-15 ° С.
For taking a shower comfortable temperature is approximately 40 ° C, for dishwashing - 45 ° C.
A shower requires a water flow of approximately 4 l / min. Then in winter period time to ensure water heating up to 40 degrees, a heater will be needed
4 = 14.3 W / (45 - 5)
That is, W will be approximately 11 kW.
Below is a table that allows you to roughly calculate the required parameters of hot water supply for various purposes:
|
Purpose of consumption |
Required water temperature, ºС |
Required water consumption, l / min |
|
Hand washing |
||
|
Kitchen sink |
||
You can also use a simpler calculation of the power of an instantaneous electric water heater. To do this, multiply the required flow rate in l / min by 2.
Which instantaneous water heater is better?
When choosing an instantaneous water heater for your apartment, one should proceed not only from the values of the provided flow rate and heating temperature, but also pay attention to the ease of use and safety of the device.
All other things being equal, it is better to choose a heater that will have protection against overheating, indication of switching on and heating, a water filter, as well as a good complete set, including the necessary fittings, electrical wire with a fork, shower head or spout.
Below are summary tables of models of instantaneous water heaters, which are quite suitable for hot water supply during the period when hot water is turned off in the house.
The tables show the dimensions of the heaters, power and price.
Water heatersThermex Sistem
|
Model |
Productivity, l / min |
Dimensions, mm |
power, kWt |
Connection |
Price, rub |
|
6 kW / 220 V |
|||||
|
8 kW / 220 V |
|||||
The presence of hot water is one of the indispensable attributes comfortable life... The townspeople are so accustomed to such conditions that the temporary shutdown of the hot water supply becomes a lot of inconvenience. There is also not enough hot water outside the city, at dachas. Decide this problem can electric instantaneous water heater. This device can supply hot water not only on a temporary, but also on a permanent basis: you can build a hot water supply system for a private house.
Principle, device and features of work
An electric instantaneous water heater is a small device that heats the water flowing through it. Heating element - heating element (tubular electric heater) or open spiral. Heaters with heating elements are more common - they are safer and it is easier to replace the heating element. In very compact models - tap attachments, etc. - there is simply nowhere to put the heating element, therefore an open spiral is used.
The device turns on when the flow appears (the tap opens), turns off when the flow disappears. The preset temperature is reached in a few seconds, after which it is maintained constantly (with sufficient power of the heating element).
Externally, an ordinary instantaneous electric water heater is a small plastic case connected to cold water and electricity. Has one outlet for hot water. Depending on the purpose, it can supply hot water to one (individual) or several (system) draw-off points.
What parts does an electric instantaneous water heater consist of?
The structure of an instantaneous water heater is simple, there are the following elements:
- Cold water inlet. It is connected to the water supply, usually with a flexible braided hose.
- Flow sensor. Monitors the appearance of water in the device (the tap is open) and turns on the heating element. It also turns off the heating when the flow is lost (the tap was closed).
- Tank with heating element. A small container, inside which there is a heating element, bent in the form of a spiral. It is here that the water is heated.
- Hot water outlet. From the tank with water goes a tube through which heated water is removed.
As you can see, the device is simple. There is also a control panel on the cover, where the conductors from the flow sensor are brought out, and the heating element - so that you can correct the operating mode and monitor the state of the device (indication of switching on).
Types and connections to water and electricity
There are two main types of flow-through electric water heaters: pressure and non-pressure. Pressure heads are also called systemic and often have the word Sistem in the name. They plug into the gap water pipe, as a rule, have a high power and can provide two or more draw-off points with hot water.
Free-flow or customized instantaneous water heaters connect as usual Appliances- through a flexible hose or by a branch of the water supply pipe. They supply heated water to one point, have relatively low power (3-7 kW) and low cost. They exist in different forms:
If you need to wait out a few weeks of turning off the hot water supply, you can supply an individual gravity electric instantaneous water heater of any kind. If a constant supply of hot water is required, the installation of a pressure head unit will be more rational.
Connecting a pressure water heater to the water supply
Pressure or system electric water heaters are connected to the existing water supply system through the pipe break. They are cut with a tee that installed before the first branch... Shut-off ball valves are installed at the inlet of cold and hot water. They turn off the device if there is a centralized hot water supply. These cranes are also needed so that, if necessary, the device can be removed for repair or replacement.
Quality tap water leaves much to be desired and it is better to insert the heater after the filter. If there is no filter at the entrance to the apartment, it is advisable to install it either immediately after the branch to the apartment, or already in front of the water heater.
In a private house, such a unit will work if available pumping station or a self-assembled system with a hydraulic accumulator. It cuts in after all the filters, from the output there is a wiring to consumers.
Unpressurized connection to water
Non-pressure (individual) electric instantaneous water heater standard view connects as usual household appliance... There must be a branch from the water supply with a tap and a thread at the end. Using a flexible braided hose, the device is connected to the water supply.
Tap nozzles for heating water are a small group. They are mainly screwed onto the thread at the end of the spout (gander). To do this, first unscrew the mesh, which is usually installed there.
Some time ago there were quite a few of them, but they differed in their low efficiency. The nozzle itself has solid dimensions and you can't attach it to a low crane - it interferes. TO In addition, faucets with electric water heating appeared on the market, which heat water better, have the ability to adjust the temperature and are more convenient to use. They are installed in place of a conventional tap on a sink or sink. The only difference between the installation is the need for an electrical connection.
Electrical connection
Any electric instantaneous water heater is a powerful and requires a separate power line... As an exception, you can connect to the line that goes to the electric stove - the line is suitable according to the parameters. Only in this case, it is necessary to ensure that the stove and the instantaneous water heater do not turn on at the same time, otherwise the machine will work on overload.
The connection of a flow-through electric water heater is standard - from the shield, the phase from zero is brought to a two-contact RCD (it is necessary to break both the phase and zero), then the phase is also fed to the machine and only after that it is supplied to the consumer.
The connection itself can be made through a three-pin plug with a socket with a mandatory grounding connection. Alternatively, you can install a contact plate or connect a cable directly to the appropriate inputs on the heater.
Pull the power line copper wire(mono-core):
- up to 7 kW cross-section 3.5 mm;
- from 7 to 12 kW - 4 mm.
The machine is selected according to the maximum current consumption (available in technical characteristics). Take the nearest higher rating (if you take a smaller one, there will be a lot of unnecessary operations - every time you switch to maximum power). The RCD is taken one step higher at nominal, the leakage current is 10 mA.
Read more about the selection of the nominal values of automatic protection.
Control type
It is possible to adjust the operation of the electric water heater (change the degree of heating) using several regulators located on the control panel. Management can be hydraulic and electronic.
An electric instantaneous water heater with hydraulic control heats the water by a certain number of degrees. It always turns on at maximum power, even if it has several different heating modes. And even if one of the modes was set before turning off, it will turn on again from the maximum.
It also has one more feature - the water heats up by a certain number of degrees. It is necessary to change the degree of heating manually - by switching modes after switching on. Moreover, the maximum temperature delta is usually 25 ° C. That is, if at the inlet you have water of + 5 ° C, then at the outlet of such a device it simply cannot be warmer than + 30 ° C (with a full flow). This does not mean that the unit has broken down or is not working properly. This means that he simply cannot make it warmer. You can slightly correct the situation by reducing the pressure, then you can achieve a slight increase in temperature, but you will not get full-fledged hot water in such conditions from such a unit.
Electronically controlled units usually have more power and a noticeably higher price. This is due to the fact that heating elements with multi-stage power control are installed in them, and they are more expensive. In addition, the "stuffing" of such a device is more complicated - there are several sensors, in addition, it also contains a microprocessor that processes data and regulates the operation of heaters. If the unit is selected correctly in terms of power, it will be able to maintain the set temperature (usually up to 40 ° C) with a deviation of one degree.
Selecting an electric instantaneous water heater by power
Whichever type of electric water heater you choose, you need to choose the right power. That's right, in this case, it is so that it meets your expectations. The easiest way is to focus on the number of taps that will require simultaneous supply of hot water:
Not all electrical networks can withstand such capacities. Often, the total allocated power for a house or apartment is much less. In this case, it is worth considering the possibility of installing less powerful individual instantaneous water heaters or. An excellent option, but it is for those who have the ability to connect to the gas main.
Selection by water consumption (performance)
You can choose an electric instantaneous water heater according to the required flow rate. There are hot water consumption rates for different consumers. By adding the required flow rate for your case, you will get the desired figure. So, the average consumption:
When choosing, you must match both the power value and the flow rate. In this case, water at all flow points, which can operate simultaneously, will be supplied at the set temperature. If not, you will have to make sure that only one tap is open at a time.
What the market has to offer
The choice of electric instantaneous water heaters is at least large ... You can easily get confused. What should you look out for besides power and performance? On the material from which the tank and heating element are made. The tank can be copper, stainless and plastic. This information not provided by all manufacturers, but if it is not available, most likely the filling is made of plastic. It is, of course, heat-resistant, but not as reliable as metals.
Also pay attention to the minimum and maximum cold water pressure at which the unit can operate. There are capricious models that require a gearbox to be installed on our networks.
| Name | Power | Dimensions (edit) | Performance | Amount of points | Control type | Operating pressure | Price |
|---|---|---|---|---|---|---|---|
| Thermex System 800 | 8 kW | 270 * 95 * 170mm | 6 l / min | 1-3 | hydraulic | 0.5-6 bar | 73$ |
| Electrolux Smartfix 2.0 TS (6.5 kW) | 6.5 kW | 270 * 135 * 100mm | 3.7 l / min | 1 | hydraulic | 0.7-6 bar | 45$ |
| AEG RMC 75 | 7.5 kW | 200 * 106 * 360mm | 1-3 | electronic | 0.5-10 bar | 230$ | |
| Stiebel Eltron DHM 3 | 3 kW | 190 * 82 * 143mm | 3.7 l / min | 1-3 | hydraulic | 6 bar | 290$ |
| Evan B1 - 9.45 | 9.45 kW | 260 * 190 * 705mm | 3.83 l / min | 1 | mechanical | 0.49-5.88 Bar | 240$ |
| Electrolux NPX 8 Flow Active | 8.8 kW | 226 * 88 * 370mm | 4.2 l / min | 1-3 | electronic | 0.7-6 bar | 220$ |
Separately, it is worth talking about cranes with electrically heated water. They are also called a water heater faucet. They appeared not so long ago, but they are quickly gaining popularity, as they are convenient to use, they just connect.
| Name | Control type | Heating range | Operating pressure | Connection size | Power / voltage | Body material | Price |
|---|---|---|---|---|---|---|---|
| ATLANTA ATH-983 | auto | 30-85 ° C | from 0.05 to 0.5MPa | 1/2" | 3 kW / 220 V | ceramics | 40-45$ |
| Aquatherm KA-002 | mechanical | up to + 60 ° C | from 0.04 to 0.7 MPa | 1/2" | 3 kW / 220 V | composite plastic | 80$ |
| Aquatherm KA-26 | mechanical | up to + 60 ° C | from 0.04 to 0.7 MPa | 1/2" | 3 kW / 220 V | composite plastic | 95-100$ |
| Delimano | auto | up to + 60 ° C | 0.04 - 0.6 MPa | 1/2" | 3 kW / 220-240 V | plastic, metal | 45$ |
| L.I.Z. (Delimano) | hydraulic | up to + 60 ° C | 0.04-0.6 MPa | 1/2" | 3 kW / 220-240 V | heat resistant ABS plastic | 50$ |
MirCli's virtual showcase has collected on its online pages the best electric instantaneous water heaters that the market has to offer. Here you can choose a model of suitable performance and functionality. It will not be difficult to buy it: a convenient catalog and sorting filters will help you decide on the device, favorable prices will be a pleasant bonus, and short time deliveries in Moscow and Russia will satisfy even the most impatient.
Who makes the best electric water heaters?
European developers are traditionally recognized as leaders in the production of home appliances. Their products can boast of high consumer performance. The site presents famous brands from different countries, the equipment of which combines convenient operation, high-quality "stuffing", modern design with good ergonomics:
- Zanussi. Famous brand from Italy, long loved by buyers from Russia. Hot water always and without extra effort- this is the motto of the company.
- Aeg. German developer with extensive experience and impeccable reputation. Its premium quality boilers are appreciated by users from all over the world.
- Electrolux. Swedish company with production facilities in Europe and East Asia... Technology under this brand can be safely called intellectual due to the use of advanced developments and technologies.
- Stiebel Eltron. Another Germans with first-class equipment for domestic use. They can be called an example of excellent premium water heaters.
- Timberk. Low-cost and very high-quality units from a Swedish manufacturer, one of the best-selling devices for supplying hot water.
Many companies have located their production facilities in Asian countries but it didn't make it worse performance characteristics, because control is carried out at every stage of the assembly.
How to choose a suitable electric instantaneous water heater?
Several criteria will help determine the best unit that will fully meet the needs of consumers:
- Power. This is the most important metric, so it needs to be determined first. To calculate the power characteristic, you need to use the formula:
[desired flow rate in liters per minute] * ([desired leaving water temperature] - [actual entering water temperature]) * 0.073.
The result will be the minimum indicator from which you can build on.
- Functionality. The assortment has such a variety that you can find a model for literally every taste. Choose what is convenient for you - type of control, built-in security features, integrated comfort options.
- Design. With this parameter, you also need to be determined solely based on your personal preferences, as well as the location of the device.
Calculation of the power of the instantaneous water heater
When choosing an instantaneous water heater, its power is of decisive importance. The power of the instantaneous water heater can be determined based on the purpose of use (for example, shower, washing hands, etc.).
To do this, use the table below. First, determine the required hot water flow (l / min) for the highest water consumption point. Even if you will use an instantaneous water heater for several points, then select its capacity at the point of water intake with the highest required capacity.
|
Required temperature, ºС |
Required flow, l / min |
Required volume of water storage water heater, l |
|
|
Hand washing |
|||
|
Kitchen sink |
|||
Knowing the flow rate at the largest point of water consumption, the power is calculated by the formula:
P = G * ∆t / 14.3
P- power of the water heater, kW;
G- flow rate or flow rate, l / min;
∆t- the required temperature rise, ºС, ∆t = T- t in ;
T- required temperature at the outlet of the water heater, ºС,
t in- cold water temperature, ºС (in winter it is +5 ºС, in summer +15 ºС).
If you plan to use several points at the same time, then the power of the instantaneous water heater should be increased by another half.
Important! You can get a comfortable full stream of hot water using an instantaneous water heater only if its power is from 8 kW or more. It is simply impossible to install a water heater with a capacity of more than 3.5 kW in old buildings with 16-amp plugs. And in houses with electric stoves and new houses, where there are 40- or 32-ampere meters, it is permissible to install "flutes" with a capacity of up to 6 kW.
On a note. There is also a more simplified calculation. In order to estimate the required power of the water heater, you can use a simpler calculation: divide the power value (kW) in half. As a result, a fairly accurate value of the water consumption (l / min) will be obtained when it is heated by about 25-30 ºС. For example, for taking a shower, a 16 kilowatt device will provide a water flow of 8 liters per minute.
Single phase or three phase
There are instantaneous water heaters for both single-phase (up to 12 kilowatts) and three-phase network(from 12 to 36 kilowatts).
In a centralized installation, if you have the option of installing a three-phase water heater, install it as it is more powerful. The more powerful the water heater, the more comfortable and economical it is.
When installing instantaneous water heaters at each water intake point separately, install mainly single-phase ones, having previously calculated their power, as described above.
Pressure and non-pressure
According to the method of installation in the water supply network, instantaneous water heaters are divided into pressure and non-pressure.
System (pressure) instantaneous water heaters (from 4.5 kW and above). They only have water inlet and outlet. They are cut into the pipes of hot and cold water, i.e. hot water is "bred" for the whole apartment. This is very convenient, since during the period when hot water is turned off, you can not only take a shower, but also use hot water from any tap in the apartment. Such a water heater turns on and off automatically, responding to the flow of water.
The pressure water heater in the image below cuts into the water supply system and can supply all water intake points.
Non-pressurized instantaneous water heaters (from 3.5 to 8 kW) are equipped with their own shower or kitchen nozzle (it is included in the device package) and work only for one water intake point. Such devices cannot be used with other fittings than the one sold with this water heater. Such water heaters are convenient, say, in the country.
The image below shows a non-pressurized water heater. Distinctive feature gravity water heaters is the presence of a tap at the entrance to it and never at the exit.
It is recommended to use small instantaneous water heaters equipped with shower heads with a capacity of 3 to 6 kW only in summer. In winter, there are often complaints that the water heater worked perfectly in summer, but now, during an accident in the heating network, it refuses to heat the water. The reason: in summer the temperature of the “cold” water “entering” from the tap was + 15 ° C. Its small instantaneous water heater with a capacity of 3.5 kW (with ∆t - 25 °, giving 3 l / min) in the summer easily “warmed up” it by another 25 °. That is, 15 ° + 25 ° = 40 ° C is a perfectly suitable temperature for washing. And in winter, the water in the tap is colder, about 5 degrees. So: 5 ° + 25 ° = 30 ° C - under such water, of course, you will freeze. And the device itself has nothing to do with it, it works as usual, nothing has broken in it. Small instantaneous water heaters were developed for warm countries Asia, Africa. And there are no such differences between winter and summer temperatures, and the water temperature in the tap is always about + 15 °. It only needs to be slightly "warmed up".
A few words about the efficiency of instantaneous water heaters
IN household with a hot water demand of 150 l / day,.
Given the low cost of an instantaneous water heater, its compact size and the fact that it is almost always equipped with kitchen mixer or a shower head, it is reasonable to buy such a water heater for each water intake point separately, because this leads to energy savings on heating water in pipes, if the water intake points are significantly removed from the water heater.
Since the water in the instantaneous water heater heats up only during consumption, energy is not consumed to maintain the temperature of a certain amount of water, as in storage water heaters and this reduces operating costs.
In addition, instantaneous water heaters minimize water consumption due to the fact that the user does not have to wait long for the water of the required temperature to flow.
Instantaneous water heaters are very durable. Their service life is more than 20 years, while those of the cumulative ones are 8-10 years with proper maintenance.
Price and brand
After you select for yourself several alternative models according to the above characteristics, all you have to do is call our office, if you need to ask all your questions, clarify what is available now and choose the water heater that suits you best for the price and by manufacturer's brand.
The best quality instantaneous water heaters are Aeg and Stiebel Eltron, so it is these firms
A flow-through household water heater does not need a special storage capacity... The principle of its operation is that the required amount of thermal energy is communicated to the flow of water in that short period while it passes through the device.
- through electrical energy heating a heating element or an uninsulated metal spiral;
- using a gas burner;
- using a heat exchanger in which water receives thermal energy from any coolant.
The last of the listed options is extremely rare; one of the first two is much more often used.
In order to choose the right instantaneous water heater for an apartment, you must consistently answer a number of questions:
1. Energy source: gas or electricity? If there are chimney ducts in your house and the housing office allows the installation of gas equipment, then the most preferred option there will be a gas water heater installation.
The power of a standard gas burner is sufficient even for heating shower water in winter. If your house is not equipped with chimneys, then you will have to install electric water heater.
Its maximum capacity depends on the type of existing wiring.
For example, in old houses, in the shields of which fuses are installed, designed for a maximum current of 16 amperes, water heaters with a capacity of no more than 3.5 kW can be installed.
During the construction of houses in a later period, power grids were laid, designed for 32 and even 40 amperes.
Such wiring will withstand a heater with a power up to 8 kW. If you want to install a more powerful unit, you must agree with the electricity supplier to lay a separate power cable.
It should be borne in mind that instantaneous water heaters with a capacity from 8 kW are designed for three-phase voltage.
Thus, in apartment buildings powerful "flutes" are used quite rarely, this option more suitable for individual construction.
Video - types and types of electric instantaneous water heaters:
2. Type of water heater: pressure or gravity? For hot water supply to the entire apartment, you will have to install a pressure water heater, which cuts directly into the cold water supply riser.
Such equipment is capable of providing hot water to several points of draw-off. If you just want to comfortably take a shower during the summer outages of hot water, choose a gravity heater.
As a rule, such devices have low power and are equipped with shower heads. However, it must be borne in mind that they are suitable for heating water in the summer.
In winter, when the temperature of the water in the pipes drops to 5 degrees, there will be little sense from a low-power free-flow "flow".
3. What capacity of the water heater do I need? It will be much easier for you to determine not so much the power as the water flow at known inlet and outlet temperatures.
It is this parameter that the manufacturer indicates in the passport of his equipment. Open the water in the usual mode and notice how long it will take, for example, a bucket of water with a capacity of 10 liters.
Calculate the received data into an expense per minute and feel free to go to the store. Now you can definitely choose the most suitable instantaneous water heater.
Be wary of buying questionable products or outright fakes, even if the seller promises you a substantial discount.
Poor quality electrical or gas equipment will not only add to you the hassle of repairing, but also may cause fires or explosions, the consequences of which will cost much more.
When buying equipment, ask the seller to show quality certificate, and also inquire about the warranty period for this equipment.
Popular electric heaters (cost and characteristics) ^
As already mentioned, the use of a powerful instantaneous water heater in an apartment is associated with great difficulties.
Therefore, in this review we will only tell you about devices low power, which occupy leading positions in terms of sales. In our country, the following brands have proven themselves well:
1. "Atmor Summer" (power - 3.5 kW, consumption - up to 3 l / min). Inexpensive heater budget class... Able to "give out" the temperature of 40 degrees, provided that at the inlet it is not lower than 18. Approximate cost - 800-1500 rubles.
2. "Polaris Vega T 5.5" (power - 5.5 kW, consumption - up to 4.4 l / min). A compact device with slightly higher power.
Easily and conveniently mounted under a bathtub or washbasin, absolutely not pretending to be free space in the bathroom. It is completed with a tap or a shower head (depending on the place of installation).
3. "Proton" PEVN 5.0-220 (power - 5.0 kW, consumption - 5 l / min). The approximate cost of this Russian model is 2500 rubles.
This device, like other domestic production, is good because its creators tried to take into account the low quality of water in our water supply networks. Due to this, it is characterized by increased service life.
4. "Stiebel Eltron DHC 3" (power - 3.0 kW, flow rate - up to 3 l / min). This manufacturer can be safely attributed to the premium class, which, of course, was reflected in the cost of the model: 8000 rubles.
But for this money you get, as motorists like to say, “full stuffing”: double protection against overheating, protection against water ingress (IP24), reliable German automation, as well as a convenient and informative indicator system.
5. "AEG MP 8" (power - 5.0 kW, flow rate - up to 4.4 l / min). Another solid brand, the cost of one model fluctuates within 7500-8000 rubles.
A reliable and unpretentious device, a relatively high price is fully justified by the quality and functionality.
Any water heater requires periodic replacement of the heating element. Read all about the shades for water heaters here in this article:
, learn how to choose, replace, where to buy.
Flow type gas water heater ^
This type of instantaneous water heater is better known as gas water heater... As already mentioned, the installation of such equipment requires agreement with the gas services, and also requires a chimney. Exists two ways to ignite a gas burner:
1. Ignition with a wick. Such a column has a small gas wick that is lit once, for example, in the morning and burns throughout the day.
It is from the wick that the gas burner ignites when the water tap is opened. Such an ignition system is cheaper, but it is characterized by inefficient use of gas.
2. Piezoelectric. A similar principle is often used in lighters for kitchen stove... This system is battery operated, the spark is supplied automatically when the tap is opened.
Inexpensive gas flow models are hydraulically controlled. This means that the water flow simply turns on gas burner without adjusting its power.
In more expensive models installed "smart" electronics, which analyzes the power of the water flow, the temperature at the inlet and outlet of the device.
In accordance with the data obtained, the valve on the burner is controlled, so that the unit always operates in optimal mode.
An important requirement: in the room where the gas water-heating equipment is installed, the window must be ajar.
This is done to avoid carbon monoxide poisoning.
Do-it-yourself installation of the "flute" ^
1. Connecting the heater to the water supply system. It is believed that the most common low-power instantaneous water heaters serve exclusively in the summer, when the hot water supply is turned off for preventive purposes.
Therefore, there is no need to make major changes to install such a device. It is most rational to connect the outlet pipe to the shower tube, and the inlet pipe through a tee to the cold water supply system.
More powerful pressure water heaters, like boilers, connect by return scheme.
2. Connection to the mains. Even if the water heater has an average power - about 6 kW - it is still necessary to connect it it is necessary to pull a separate wire from the shield.
This has to be done for the reason that most meters are not designed for such a current load (approximately 27 amperes).
The wire cross-section and the type of circuit breakers (in this case, you need to install an RCD) are selected according to special tables. Remember that the socket into which the water heater is connected must have a ground wire.
3. Connection to the gas main.
It is forbidden to make such a connection on your own!
After gas water heater mounted and connected to the water supply system, you must invite a representative gas service, which will connect the equipment to the gas supply system.
A small video about the pros and cons of instantaneous water heaters:
