Water heaters flowing electric for the apartment. Connecting a pressurized water heater to the water supply

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Competent choice of instantaneous water heaters

For modern man highly appreciating life comfort, the problem of providing hot water of your home (if it does not have a centralized hot water supply, annual preventive maintenance of utilities is practiced, or there are regular interruptions in the supply of water) is very relevant. In many cases, it can be solved by purchasing and installing special equipment- water heater. However, his right choice- one more problem.

Exist different types heaters classified according to the type of energy source they use (gas, electric), according to the principle of water heating (accumulative, flow), according to power, volume, etc. At the same time, a flowing water heater (the so-called column) is of particular interest to consumers, which does not limit the residents of the house in the amount of liquid used and thereby provides a higher level of comfort.

Pros and cons of flow devices

The choice by many Russians of flow-through water-heating equipment, in which the heating of the liquid is carried out when passing through the water heater, is due to the undoubted advantages of this type of apparatus:

Unlike storage devices, when using which heated water inevitably ends after a certain time (depending on the volume of the tank) and cold water begins to flow, the instantaneous water heater provides unlimited uninterrupted supply hot water.

Scheme of using the instantaneous water heater: When operating the water heater, it is necessary: ​​close the valve - "2", open the valves - "1", "3", "4"; when the water heater is not in use: close taps - "3", "4", open taps - "1", "2".

A tankless water heater is much smaller than a storage water heater because it does not need a reservoir to store the liquid.

Compared with these significant advantages, the disadvantages of flow heaters do not look so significant:

1. Sufficiently large one-time power consumption.
2. If several points of water intake are connected to the flow device at once (for example, taps in the bathroom and in the kitchen), then the water temperature will depend on the number of simultaneously operating points. Thus, if both taps are used at the same time, residents will either have to be content with less heated water, or increase the capacity of the water heater.

In general, it should be noted that the choice of a water heater should be based on an analysis of the following factors:

• to which communications there is the possibility of a more convenient and economical connection: to an electrical network or a gas pipeline;
• what space does the living room have for installing a water heater (if there is free space, it is possible to use a storage device big size, if they are deficient, a compact flow heater is required);
• Is it possible to use more power indoors.

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Features of electric instantaneous water heaters

The electric instantaneous heater produces water heating with constant use of electricity. The principle of its operation is as follows: inside a small special chamber there is a thermal element - a tubular electric heater, or heating element, which is a metal (most often copper) tube filled with a special heat-conducting electrical insulator and equipped with a conductive thread in the center.

The latter is made of nichrome and has a certain resistance, which allows you to transfer the required specific power to the surface of the heater. When the device is connected to the network, the heating element heats up and transmits thermal energy fluid passing through the water heater.

As noted above, the main advantage of this type of heaters is their compact size. In addition, they are environmentally friendly. The main disadvantage is that they require a lot of power (6-27 kW), respectively, special electrical equipment in the room (devices more powerful than 5 kW are not even supplied with a cord and plug, so that users do not plug such a water heater into a household electrical outlet).

Selection of heaters of this type mainly depends on their performance, which is determined by 2 factors:

• incoming water temperature;
• the power of the device itself.

Most heaters of this type are equipped with a system automatic start at the start of the drawdown. The flow device is quite capricious: it needs a strong and constant pressure of water, which is associated with the peculiarities of its device. In case of insufficient pressure, there is a high risk that the heating element will burn out, and the manufacturer will rightfully refuse the buyer in warranty repairs.

Therefore, experts strongly do not recommend installing flow devices in country houses not connected to the system centralized water supply, and on upper floors urban buildings located in areas of long-standing development, where water pressure is usually unstable. This problem can be solved in them by installing pressure-boosting pumps that are mounted in the supply line.

Optimal comfortable conditions are created when using a water heater whose power exceeds 5 kW. When choosing equipment, you need to remember that there are devices for both single-phase (no more than 12 kW) and 3-phase networks (from 12 to 36 kW). For correct column comparison various manufacturers it is advisable to pay attention to what power appears in the description of the device - consumed or useful. These 2 quantities are interconnected by the efficiency of the apparatus (coefficient of performance). It is recommended to compare equipment by useful power, which is provided at the outlet of the dispenser.

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What else to consider when choosing an electric heater

Flowing electric heaters are divided into 2 large groups:

1. System (pressure), with a capacity of 4.5 kW and above. In such models, only the inlet and outlet for the liquid are provided. They crash into pipes hot and cold water for distribution to the entire dwelling. This is very convenient, because during periods when hot water is turned off, it becomes possible not only to take a shower, but also to use hot water from any tap in the apartment. Such a water heater turns on and off automatically when the water is started and the tap is turned off, respectively.
2. Non-pressure with a power of 3.5 to 8 kW, equipped with its own kitchen or shower head, which is included in the device. Such water heaters work exclusively at one point of water intake and are most often used in the country. For devices of this type, it is impossible to use other fittings than the one that was sold complete with a heater.

Small flow heaters with a power of 3-6 kW, equipped with shower heads, experts recommend using only in summer period. In winter, consumers often complain that the water heater, which worked perfectly in the summer, now suddenly stops heating water normally. And the reason is that in summer the temperature of unheated water was about +18°С.

And a small water heater with a capacity of 3.5 kW with a delta of 25 ° C, giving 3 liters per minute, easily warmed the water to a comfortable 40 ° C for washing. And in winter, the incoming water is much colder (average 5°C). And it turns out: 5 ° С + 25 ° С = 30 ° С. Under water of this temperature, a person naturally feels uncomfortable.

And the equipment itself has nothing to do with it, nothing has broken in it, it functions as usual. Just small flow heaters developed for warm countries (mainly Africa, Asia, Latin America), where there are no large differences between winter and summer temperatures, and the incoming water all year round about +15°С.

Given the low cost of such equipment, its compact size and configuration features, it is reasonable to buy a small flow heater for each water intake point separately. This ensures energy savings in heating water in the pipes leading it to the water intake points, if the taps are significantly removed from the heater.

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Geysers

All instantaneous gas water heaters have the same design, the main elements of which are a burner used to heat water, and automation that provides safe work. The main indicator characterizing gas water heaters is power (as for electrical appliances).

The higher the power of the unit, the greater the performance it has. For example, when heating cold water from 10 ° C to 35 ° C, a 17.4 kW gas water heater is able to provide 10 liters of hot liquid per minute, and a column, whose power is 27.8 kW, under similar conditions, allows you to get 16 liters of heated water in a minute. In more detail, the dependence of the heating rate and volume of water on the power of the column is given in the following table:

In this regard, gas columns are divided into 3 groups:

• low power (17-19 kW);
• medium power (22-24 kW);
• high power (28-30 kW).

For many people, choosing an instantaneous water heater becomes complex process because you need to know the features of their internal structure, pay attention to the nuances in the classification and correctly calculate their power. Such helpful tips useful to everyone, so you should keep them with you.

How is a flow heater

The best option for uninterrupted supply of hot water in small apartments, there will be a flow-through water heater for the shower, which, unlike storage, has a small size. Due to the installation of a powerful heating element in them, the heating element heats up water quickly, providing an unlimited amount of hot flow. According to the installation method, there are instantaneous water heaters for a residential apartment of pressure and non-pressure type.

Pressure water heaters are installed directly to the water supply riser, and pressureless water heaters are installed close to the water supply point. If the apartment is gas stoves, then it is recommended to buy a low power heater, because there may not be enough wiring parameters to ensure normal operation device. If the house has electric stoves, then you can choose more powerful units.

The principle of operation of instantaneous water heater

To understand how it works flow boiler to heat water, you need to consider its type: it can be electric and gas. An electric water heater involves heating water when passing through a heating element with a power of up to 27 kW. Heating turns on when the tap is opened, and turns off when it is closed. When supplying hot water, energy is continuously consumed. Heating takes half a minute to a minute, and the power is up to 3 kW. Of the minuses - electric types cannot supply hot water to several points at once.

The gas water heater for the apartment is connected to a gas pipe, when the tap is turned on, the fire is ignited, the gas burns and heats the water. It is more difficult to install because it requires a gas pipe, water supply and chimney where all the burnt particles go. Combustion air is fed into a special chamber, so experts advise installing this type in a well-ventilated or ventilated area. Ignition is carried out by installing batteries or an electric generator. The manual option to turn on the ignition suggests that you must not forget to turn it off.

How to choose an instantaneous water heater

When a person buys instantaneous water heaters for an apartment, it is important for him to remember the following characteristics:

• Profitability - the price of electricity is higher than gas.
• Availability of necessary communications for heating, electricity, water supply, gas.
• The required volume of hot water is up to 15 liters for washing hands, 50 for a shower, and 100 for a bath.
• Power, performance - if you want to take a shower and wash dishes at the same time, then the power should be 24 kW, and if each process is carried out separately, its value will be only 19 kW.
• Safety - when choosing a gas domestic heater, it is better to choose automatic system blocking the gas when the device is not in use; when choosing an electric one, it is necessary to take into account the load on electrical network, because houses with gas can not withstand the power, so you have to change the wiring and shield.
• Required temperature - the maximum is 75 degrees.
• Availability of free space - electrical occupied less space, are transferred to any convenient place, while gas ones require more space, bulky.

Prices for instantaneous water heaters for an apartment

The cost directly affects the choice of instantaneous water heater for an apartment. There are two options for purchasing: contact the specialized departments directly or buy from the online store through the catalog. The second option allows you to select a device of the required parameters, order free delivery, as in Ulmart. Prices for popular models Electrolux, Water heater, Termex start at 3000 rubles. Gas and industrial Electrolux, Vortex are more expensive, prices are set from 8000 rubles. The greater the power and the volume carried, the higher the price will be.

Instantaneous water heater installation

A popular question among users of the appliance will be how to install an instantaneous water heater in the kitchen or bathroom? This process includes following algorithm:

• Choose the installation location in the apartment, taking into account the ingress of moisture on it (this must be excluded), the convenience of turning it on and off, using it, adjusting the position of the tap, connecting to a sink or sink, water supply or gas pipes.
• Selection of special devices: an anode or others, if the type of water is hard.
• Installation begins with the choice of a place, with a conclusion to vertical position.
• Fixing the device to the wall with dowels or screws.
• When installing a gas water heater, the wall should be prepared: it should be galvanized, have refractory plaster or tile on it.

Interruptions in the supply of hot water, especially in the summer, happen with enviable constancy. To solve this problem, many are forced to equip an autonomous source of hot water in their apartment. Quite often, our choice stops at a flowing electric water heater. Of course, you need to decide which instantaneous water heater is better and how to choose the right model.

The instantaneous pressure water heater under the sink is invisible and useful

These units are different small size, low power consumption, and in terms of efficiency no worse than modifications accumulative type. In such devices, the liquid is instantly heated and you can not be afraid that, when taking a shower from the horn, you will find yourself under a cold stream of water, because the hot one has ended in storage tank.

How does an instantaneous water heater work?

A flowing water heater is a plastic or metal casing, inside of which there is a tubular electric a heating element(TEN). The principle of operation of an instantaneous water heater is not complicated: the cold water entering the inlet of the apparatus, in contact with the heating element, acquires the desired temperature at the outlet. Energy is consumed only during the operation of the device. The best instantaneous water heaters have the following advantages:

• low weight and overall dimensions;
• the possibility of placing in any convenient place;
• unlimited amount of heated liquid;
• electricity consumption in interval mode;
• small price.

Internal organization instantaneous water heater - example modern technologies

It must be understood that the more often the water heater works similar design, the greater will be the cost of paying bills. Basically, it depends on the number of people living in the apartment, the location of the water intake points, and so on. The best low-power flow heaters used in the country are very economical.

Which is better: electric or gas water heater?

Flowing water heaters, depending on the energy source used, are divided into electric and gas. The principle of operation is essentially the same, so you need to choose a source of energy. Asked if it's better geyser or electric water heater, there is no single answer: each unit has its own advantages and disadvantages.

Price gas fuel below, but to install gas water heaters equipment required exhaust ventilation with a chimney and compliance with a number of fire safety requirements.

The geyser requires a special permit from the relevant authorities, which means that do-it-yourself installation is prohibited, and a certified specialist is needed.

In addition, the geyser requires constant Maintenance, and for the operation of the unit, it is necessary to have a constant working pressure in the gas line. They have large overall dimensions, have restrictions on the installation site and burn oxygen.

A small size instantaneous water heater will harmoniously fit into any interior

Instantaneous water heaters, which are powered by electric current, are much safer to use. Their installation is not difficult and can be done by hand. It must be taken into account that powerful models put an increased load on the wiring, so a safe connection should be provided. These units are compact in size and can be installed anywhere.

What is the difference between pressure and non-pressure models

Non-pressure models are distinguished by the fact that the internal pressure in the system is close to atmospheric. Pressure modifications are always under pressure from the fluid of the water main. Pressureless water heaters do not have big power, as a result, they weakly heat water and are used mainly as auxiliary devices for hot water supply, they work great in summer cottages.

The water heater can be built right into the faucet

The package of non-pressure models, designed to service one water intake point, includes a shower hose, watering can or faucet. Units of this type do not exert an increased load on the electrical network to which they are connected, so replacing the wiring with a more powerful one is not required in most cases. This is again convenient for giving. Non-pressure models are always installed after a tap or faucet that blocks water access.

Instantaneous water heater option with tap

Pressure water heaters are mounted directly into the distribution of the water supply network and can serve several water intake points at the same time. Most often they are installed under the sink, hung on the wall or placed behind the door. kitchen furniture. These units can maintain a constant temperature regime heated water and automatically turn on when the tap is opened.

Connecting water heaters

Water heaters are connected to engineering communications water supply and electrical energy. At the same time, there are differences in the wiring of pressure and non-pressure models, but grounding must be done in any case. Non-pressure water heaters are much easier to connect to a water source.

The water heater under the sink takes up very little space

Pressure units are connected to two water supply lines, through which hot and cold water is supplied. In almost any case, it will be correct to equip the power supply with a separate line, since overloading the existing wiring is unacceptable, and all safety requirements must be observed. Electrical installation of water heaters operated in rooms with high humidity must be carried out with particular care.

Connecting a non-pressure model to a water source

The installation of an instantaneous water heater always starts with hydraulic installation, because it is necessary to squeeze out air pockets and fill its body with water. Connecting a non-pressure model to a source of cold water is not difficult and can be done by hand. The device is mounted through a gasket that has dielectric properties and is included in the device package.

Heated shower head - another instantaneous water heater option

A mixer must be present at the heater inlet or stopcock. This is necessary so that in the container in which the liquid is heated to the desired temperature, pressure is not created for which it is not designed.

If a shut-off valve is connected at the outlet of the water heating device, a container rupture may occur, since the automation that controls the workflow does not monitor the pressure of the liquid at the place of its heating, but controls its presence or absence only at the system inlet.

The supply of hot water coming from the water heater is carried out through a long hose with a shower arm or gander. It is not possible to replace the faucet or spiral hose supplied with the unit, as they are specially designed for the required heating and economical water consumption. During operation, it is necessary to exclude the ingress of water splashes on the unit and the provision of external mechanical impact on it.

Connecting a pressurized water heater to the water supply

Pressure execution of a water heater provides connection to a water supply system in a section of pipeline system. A tee is used, installed to the nearest pipe branch. In order to be able to turn off the unit with a centralized supply of hot water, liquid shut-off valves are installed on the inlet pipes.

Connecting a pressurized instantaneous water heater to a faucet

In addition, their presence helps to remove the device for repair or replacement without blocking the center line. Before the tee it is better to install a filter for cleaning tap water, since its quality in the vast majority of cases can lead to a reduction in the life of the device.

Electrical installation

The electrical installation of the instantaneous water heater is carried out after it is fixed in the selected place and the device body is filled with water. Low-power models can be plugged directly into an outlet. If the apartment has electric stove, the cable that feeds it is activated.

Wiring diagram for connecting instantaneous water heater

For some powerful units, three-phase network equipment with a nominal voltage of three hundred and eighty volts is required. In all cases, it is imperative to provide for the implementation of high-quality grounding. In addition, a residual current device is necessary, which interrupts the operation of the unit in the event of a danger of human injury. electric shock. Detailed instructions about connecting RCD you will find in the article

Control options for water heaters

The efficiency of their functioning largely depends on the quality of control of water heaters. There are the following implementations of this function:

• Devices that use automation hydraulic type. In this case, a special sensor is located at the system inlet, which controls the appearance of the flow of sheath fluid and turns on the heating element. The disadvantage of this design is that it connects only one level of heating power. In some models, it can be changed manually by push-button switching.
• Using an electronic microprocessor. It controls the operation of the heater using monitoring sensors and allows you to maintain the same temperature regime of the heated liquid.

Hydraulic control makes it possible to obtain an increase in the temperature of the serviced liquid only by a certain amount. Which one depends on the power of the tubular electric heating element. It is believed that the temperature of the water at the entrance varies from twenty to twenty-five degrees.

It turns out that in summer the hydraulic control allows you to provide hot water, but in winter the unit may not be able to cope with heating too cold water.

Electronic control allows you to maintain the desired temperature of the heated liquid, regardless of the time of year. Such units are much more expensive and have more power, as a result of which they require a separate connection line and the mandatory installation of a residual current device.

Determining the required capacity of an instantaneous water heater

The power of an instantaneous water heater is its most important operational parameter. It determines the amount of hot water heated by the unit for a certain period of time. A low-power unit is able to heat about five liters of water within a minute, enough for cooking dinner or taking a shower.

The power of an instantaneous water heater required to meet the demand for hot water can be simply determined by dividing this parameter by half. The result obtained will show quite accurately how many liters of liquid, the temperature of which will increase by approximately thirty degrees, will be consumed in a minute interval. For example, a unit with a capacity of eighteen kilowatts will provide an output of nine liters of hot water per minute.

By determining the daily consumption of hot water depending on the number of people living in the apartment, you can easily calculate the required capacity of the instantaneous water heater. It increases by about one and a half times if a bath is taken instead of a shower, and there are many water intake points.

Depending on the design and purpose, the power of the water heater will be different.

In practice, in the case of using a non-pressure water heater with a tap, a power of 3.5 kW is sufficient. If you need to heat water only for the shower, choose a device with a power of 5 kW. In the case of the possible use of a shower and a tap at the same time, it is better to purchase a water heater with a power of 7 kW.

Assessment of possible water consumption

The possible water consumption is estimated depending on the size of the family living in the apartment, the presence or absence of a bathroom, and so on. What will be the average water consumption for an average family of three? Let's try to figure it out.

Taking a shower, an adult man spends about fifteen liters of hot water, a woman, on average, ten liters more. Adding here morning hygiene procedures, washing dishes and hands, we get that a family of three will spend about a hundred liters of water. At the same time, thirty liters will be enough for one person.

Real offer on store shelves

On the modern market There is a huge variety of modifications of instantaneous water heaters, both pressure and non-pressure. Real Deals pressure models can be compared using the following table.

Table of characteristics of instantaneous water heaters
Name of the water heater	Number of points	Powerful, watt	Dimensions, mm	Productivity, l/min	control type	We stand, %
Electrolux Smartfix 2.0TX	1	6500	270x135x100	3,7	hydraulic	100
Thermex System 800	1 to 3	8000	270x95x170	6	hydraulic	160
Electrolux NPX 8 Flow Active	1 to 3	8800	226x88x370	4,2	electr	490
AEG RMC 75	1 to 3	7500	200x106x360	1 to 3	electr	510
Evan W1-9.45	1	9450	260x190x705	3,8	mechanical	530
Stiebel Eltron DHM3	1 to 3	3000	190x82x143	3,7	hydraulic	660

When choosing a specific device for a house or apartment, it is necessary to take into account the totality of all operating parameters. Most important part instantaneous water heater is a tubular electric heating element. For long-term trouble-free operation of the unit, it is necessary to protect this part from direct contact with the heated liquid. Other structural elements in contact with water must be made of brass, copper or stainless steel.

The body of the instantaneous water heater is exposed to high temperatures, aggressive chemical components in the composition of the liquid flowing through it, therefore it is made from chemically and mechanically durable material. Materials such as copper and polypropylene have proven themselves well, the cases made from them are distinguished by a long service life.

It is convenient to install such a kit instead of a regular crane.

An important factor is the convenience of using the unit for all family members. It is very important to ensure the safety of operation, you need to choose a device with an overheating protection function, complete it with a filter for water purification. It will be useful to have an indication of inclusion, a scoreboard on which the temperature of the heated liquid is displayed.

They have such significant advantages over accumulative ones as compact dimensions and instantaneous heating of water. But their connection requires a separate electric cable and automatic protection on the shield.

Therefore, the installation of instantaneous heaters is limited in apartments. multi-storey buildings old building - here you can put a heater with a power of not more than 3.5 kW.

Calculation of the required power

The power of the 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 amount of water needed for various needs:

Purpose of use		Water flow, (l/min)	Required volume of water, (l) for storage water heater
hand washing
Kitchen sink
Taking a shower
Taking a bath

The power of a flowing electric water heater is calculated by the formula:

P=G*∆t/14.3 where:

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

This indicator can be determined more simplified method- just divide in half the power of the water heater you like. The result is a fairly accurate water flow (in l / min) when it is heated by 20-30º C. For clarification - 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, and not just for showers, then you need to focus on the power of the largest point of water intake. 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 it is possible to get a lot of hot water immediately with a small instantaneous water heater with its performance of 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 be able to provide the consumed electrical power. In this regard, single-phase and three-phase instantaneous water heaters are produced.

Pressure and non-pressure instantaneous water heaters

Water heaters flow type, in addition, are divided into pressure and non-pressure. Pressure electric heaters (they are also called "system") 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. Turning on and off 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 of 3.5 to 8 kW, includes shower and kitchen nozzles. They work only for one water intake point. It is convenient to use such heaters in the summer in the country.

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

Since a non-pressure heater cannot provide a large number of water, the holes in the shower heads of the heaters are specially made very small so that the jet is stronger. With high water hardness, it is necessary to rinse the nozzles more often with a solution that removes scale, otherwise the holes may become clogged and overheating of the device will be inevitable.
Most pressureless instantaneous water heaters with low power designed for use in countries with a warm climate, where the average annual temperature fluctuations are small.

Therefore, in winter middle lane they will be ineffective as they can heat water up to 30º C.

Review of brands and manufacturers. Price comparison

In the market of electric water heaters, flow 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).

Compare the features and prices of some well-known brands

Instantaneous electric water heaters Electrolux

Electrolux produces several series of heaters of various capacities, which are equipped with additional functions.

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

brand		power, kWt	Price, rub
MULTYTRONIC,	Electronic control, with color and black LCD displays
ELITEC	Electronic control
SENSOMATIC	Touch control
MINIFIX	Hydraulic control

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 - the optimal ratio of price and quality.

brand		power, kWt	Price, rub
STREAM	Non-pressure, combi
EDISSON	System, 220 V

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. Instantaneous water heaters Kospel have a nice design, modern, and their service maintenance low-cost.

brand		power, kWt	Price, rub
EPP	High power system
EPVE	Systemic with electronic control and LCD display
EPPV	System with electronic power control
EPV	System with hydraulic power control

Summing up

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

1. Ask your service organization 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. Decide on the complexity of installing the device and understand whether it is possible to cope with this on your own or whether it is necessary to invite electricians and plumbers, find out the cost of installation work and installation.
3. Before choosing an instantaneous electric water heater it is worth asking about warranties, availability of replacement parts, their cost and find out where the nearest service centers are located.

This will help save time, effort and money.

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

Calculation of the power of instantaneous water heater

When choosing an instantaneous water heater crucial plays its power. The power of an instantaneous water heater can be determined based on the purpose of use (for example, showering, washing hands, etc.).

To do this, use the table below. First determine the required hot water flow (l/min) for the largest hot water point. Even if you use a tankless water heater for several points, then select its power according to the water intake point with the largest required power.

	Required temperature, ºС	Required flow, l/min	Required water volume of 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– water heater power, kW;

G– flow or flow, l/min;

∆t– required temperature increase, ºС, ∆t = T-t in ;

T- required temperature at the water heater outlet, ºС,

t in– temperature of cold water, ºС (+5 ºС in winter, +15 ºС in summer).

If you plan to use several points at the same time, then the power of the instantaneous water heater should be increased by another one and a half times.

Important! It is possible to get a comfortable full-fledged stream of hot water using an instantaneous water heater only if its power is from 8 kW and above. In houses of old buildings with 16-ampere plugs, a water heater with a power of more than 3.5 kW simply cannot be installed. And in houses with electric stoves and new houses where there are 40- or 32-ampere meters, it is permissible to install “flow-throughs” with a power 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 water flow (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 networks (from 12 to 36 kilowatts).

With a centralized installation, if you have the opportunity to install 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 predominantly single-phase ones, having previously calculated their power, as described above.

Pressure and non-pressure

According to the installation method 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 provide inlet and outlet for water. They are cut into hot and cold water pipes, i.e. hot water is "bred" to the whole apartment. This is very convenient, because during the period of hot water shutdown, 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, reacting to the flow of water.

The pressure water heater in the image below cuts into the water supply system and can power all water intake points.

Non-pressure instantaneous water heaters (from 3.5 to 8 kW) are equipped with their own shower or kitchen nozzle (it is included in the device kit) and work only on one water intake point. Such devices cannot be used with other fittings than the one that was sold complete with this water heater. Such water heaters are convenient, say, in the country.

The image below shows a pressureless water heater. Distinctive feature non-pressure water heaters is the presence of a tap at the entrance to it and never at the exit.

small instantaneous water heaters, equipped with shower heads with a power of 3 to 6 kW, it is recommended to use only in summer. In winter, there are often complaints that the water heater worked fine in summer, and now, during a heating network failure, it refuses to heat water. Reason: in summer, the temperature of “cold” water “incoming” from the tap was + 15 ° C. His small instantaneous water heater with a capacity of 3.5 kW (with ∆t - 25°, giving 3 l / min) in the summer easily "heated up" it by another 25°. That is, 15° + 25° = 40°C is quite a suitable temperature for washing. And in winter, the water in the tap is colder, about 5 degrees. So: 5 ° + 25 ° = 30 ° С - 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 the warm countries of Asia and Africa. And there are no such differences between winter and summer temperatures, and the temperature of the water in the tap is always about + 15 °. It just needs to be warmed up a bit.

A few words about the efficiency of instantaneous water heaters

IN household with the need for hot water 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 a kitchen faucet or shower head, it is reasonable to buy such a water heater for each water intake separately, because. this leads to energy savings in heating water in pipes if the water intake points are significantly removed from the water heater.

Since the water in the instantaneous water heater is heated only during consumption, no energy is spent on maintaining the temperature a certain amount 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 to reach the required temperature.

Instantaneous water heaters are very durable. Their service life is more than 20 years, while the accumulative 8-10 years with proper maintenance.

Price and brand

After you have selected several alternative models for yourself according to the characteristics described above, you will only have to call our office if you need to ask all your questions, clarify what is currently available and choose the water heater that suits you best for the price and by manufacturer's brand.

The highest quality instantaneous water heaters are Aeg and Stiebel Eltron, so these are the companies