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How the boiler with a dry heater works

What is a water heater with a dry heater, how long it will last and whether it is worth buying it?

The water heater in the country house and in the country house. a vital necessity. Today we will talk about a relatively new kind of this device. a water heater with a dry heating element. What is it and is it worth buying?

The “heart” of any water heater is a heating element. This is what determines the efficiency and durability of the device. Probably each of us is familiar with an open or “wet” heating element. a curved copper tube with a nichrome spiral inside. It can be seen, for example, in old models of electric kettles. The main disadvantage of this heating element is that it is in direct contact with water. The salts contained in it settle on the metal surface, forming a scale. It has to be removed regularly, which is quite a nuisance for housewives. And if you skip a couple of cleaning sessions, the deposits will harden and the appliance will be hopelessly ruined.

Dry heating elements that have recently appeared on our market do not cause these problems. In devices of this kind, the heating element is placed in a metal bulb. It has no direct contact with water which minimizes the white deposit formation. If the bulb has an anti-corrosion coating, the sludge will be even less. Therefore, according to the assurances of some manufacturers, this heating element serves up to 20 years!) years. For comparison: the lifetime of classic tubular heating elements is 4-5 years.

Durability is not the only advantage of dry heating elements. The design allows you to put in the tank a few heating elements, which ensures the fastest heating of water. over, the device power can be adjusted by turning off or on each element separately.

Dry heater is designed so that no air s can build up in it. And this considerably prolongs its service life

Dry heating elements are easy to maintain. To replace a failed heating element you can do it yourself, without a wizard, and from the tools you will need only a screwdriver.

The tangible advantage of the dry heating element is the safety. Thermal protection unit does not allow you to turn on the heating element without water. But even if it fails (and absolutely everything can break), the very design of the water heater excludes electrocution.

Of course, when talking about advantages we can not avoid to mention disadvantages as well. The first and main disadvantage is a relatively high price. Dry heaters are more expensive than “wet”, but if you want you can find a budget model that will not hurt the wallet too much.

The second drawback. the relative difficulty in maintenance. Heaters categorically can not be cleaned from limescale mechanically. brushes, metal sponges and even sandpaper are completely excluded. Only mild detergents can be used, e.g. citric acid.

How to choose a water heater with a dry heater?

When choosing a specific model, one should first of all pay attention to the type of dry heating element. precisely, on what is filled with the bulb in which it is enclosed.

Heating elements without fill are notable primarily for their low price. But their efficiency is relatively low, because part of the heat energy is literally dissolved in the air. However, these losses are small and can be neglected.

Oil-filled heating elements cope better with their responsibilities, since oil heats up and gives off heat more efficiently than air. But at the same time they are more expensive than the previous ones.

Flasks filled with white sand are the most effective, reliable and expensive. Important! For each specific model of water heater requires a different model of heating elements, so when buying should think in advance about the spare parts.

Another important point. the type and material of manufacture of the heating element. There are two variants.

Rod TENs. long thin cylinders, which are designed for tanks not more than 50 liters. You can put up to three heating elements of this type in the flask of the water heater, but you should not expect high efficiency from them. Due to the small area of the heated surface their heat output is relatively small.

Steatite (ceramic) heating elements are arranged very differently. Each such product is shaped like a wide cylinder with troughs in which a nichrome spiral is placed. The ribbed surface provides effective heating, but the material is much more interesting. steatite. This is a ceramic from recycled talc, capable of withstanding heat up to 1000 ° C. It heats up slowly and cools down slowly, giving up the heat for a long time even after the device is turned off.

Steatite heaters are more durable than rod heaters. Most of all because it doesn’t have a copper-steel pair that causes a destructive electrochemical reaction. In addition, heating elements of this type are not susceptible to stray currents.

You should keep in mind that they cost much more than the rod ones. Another disadvantage is the lack of interchangeability. This means that for each model of electric heater a heating element of its own design is made. So, in the case of damage it cannot be replaced with the first available one.

The most affordable are rod heating elements with an air layer. And the most expensive are steatite with a sandy addition

So, the dry heating element is more durable than the classic “wet”, it does not require regular cleaning, and to replace a failed heating element you can do it yourself. So if the relatively high price (about 12,000. 25,000 as of May 2022) is not a serious problem, the purchase of such a water heater is justified.

Disadvantages and advantages of dry heating element

The main advantages of this type of heater include:

  • No limescale. This is a modern heating device in which the heating element is reliably protected by the walls of the closed bulb and additionally treated with an anti-corrosion solution. Thanks to this, there is no contact with hard water and, accordingly, no scaling.
  • Water heats up quickly. Since the water heating element of the boiler has no direct contact with water and is not exposed to its deleterious effects, then the work of the device goes without interruptions, quality, with equal intervals.
  • Reliable thermal protection. Boilers of a new generation are equipped with reliable thermal protection, thanks to it, there is no heating of the device without water inside. If this unit breaks, only the heating element itself will fail, not the entire water heater.
  • Easy to maintain. Parts replacement in this unit can be done independently without resorting to expensive repair. The heating element is quick and easy to change. It is desirable to have preventive maintenance by masters in a service center once every two or three years that significantly saves money.
  • The dimensions of the boiler. These devices have smaller parameters and volumes than heaters with wet heating element, besides they have an interesting design that gives them an attractive appearance. They also have a higher water capacity than similar previous models.
  • Exclude the possibility of air lock. These models are designed in such a way that the penetration of air inside is excluded, respectively, the appearance of plugs is also impossible. It significantly prolongs the service life of the heater with a dry heater and saves money to its owner.

Disadvantages of such water heaters are few, but still they exist:

  • Inefficient in operation. First the device heats the metal tube and then the water. But this disadvantage is not always justified, since the heating is deep inside, and the indirect heating of water occurs with minimal heat loss in addition, the diameter of dry ТEН (10-12 mm) less than the diameter of a metal pipe only a couple of millimeters. On this basis we can confidently say that the air layer between the walls is too small to lose much heat during heating.
  • There is an opinion that the power to the heater with a dry heater is less than that of analogues with a wet heater. The second representatives of heaters really have a spiral power of 2,000 W, and the devices with dry heating elements have only 1200 W. But the dry heating elements in the heater is usually put two, so the power turns out already 2400 W.
  • Cost. It is higher than in models with another type of heating element, but since the advantages of heaters with dry heating element are much more, it can be considered quite justified.
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When choosing a heater for your home, it is better to choose a unit with a dry heating element. You will have very few problems with it, and it will last for many years.

Willer Elegance IVB DR

The peculiarity of this machine is a fundamentally new system of the tubular heating element, which allows for rapid heating of the water. Magnesium anode protects the tank from corrosion and extends its service life. A good machine for not much money.

Atlantic Steatite Cube VM 75 S4 CM

The French treat very responsibly to the production of various equipment and this water heater was no exception. European quality, reliability, stable operation of the boiler will please any buyer.

Ariston PRO ECO 50 V DRY HE

Another European representative of reliability and compactness. this water heater brand Ariston.


The number of manufactured water heaters with dry heating elements is constantly increasing. Consider the models of several popular foreign manufacturers.

Gorenje (Slovenia) GBF 80/UA Tank capacity. 80 liters. Power consumption. 2000 watts. Heating to a maximum temperature (75 ° C) takes about 3 hours. Weight without water. 30 kg. Temperature gauge, corrosion protection, frost protection, IP25 (electrical). The tank is made of sheet steel. Medium
Gorenje (Slovenia) OGBS80ORV9 Degree of protection. IP24. Tank capacity. 80 liters. Made of sheet steel. Enamelled casing and storage tank. Draws 2000 watts during operation. Water heats up to a maximum of 75 °. There are two protection systems: against overheating and freezing. Medium
Electrolux (Sweden) EWH 50 Formax Flat shaped model. Can be installed vertically or horizontally. Holds 50 liters of water. Weighs only about 22 kg (empty). Takes less than two hours to heat. Features a digital thermometer. Automatic disconnection in the event of an insulation fault. Medium
Electrolux (Sweden) EWH 80 Formax DL Boiler, equipped with two heating elements. The tank capacity of 80 liters is enameled glass. Rectangular shape with rounded sides. Takes three hours to heat water to 75 °. Weighs almost 28kg without fluid. Control. electronic, through a digital panel. Medium
Atlantic (France) STEATITE VM 80 D400-2-BC Accumulation boiler, holds 80 liters of water. Uses 1500 watts of power. Heating element by itself. Can only be installed vertically. Body made of stainless steel, enameled tank. Has corrosion protection. Medium
Atlantic (France) VM 150 S4CM Designed for 150 liters. Maximum water temperature 65°. Takes about 7 hours to heat. One heating element. Daily heat loss is 1.59 kW. The tank is made of metal, glass ceramic coating with the addition of titanium dioxide. The device, not filled with water, weighs 40 kg. Medium

Now you know what a water heater with a dry heater means, all its advantages and disadvantages.

Types of dry electric tube heaters

Electric heaters are divided into classifications, which are based, depending on the fundamental schemes of operation and the working environment. The specified requirements determine the strength of the heater, its design and protection from high temperature.

According to the applications the air heaters are divided into supported voltages depending on the problem to be solved. The universal heater of the classical type can be considered a 220 volt air heater. Used in household appliances, in production facilities for heating liquids in accordance with technological processes. Dry heating elements for 380 or 660 volts are used in special industries.

An ordinary dry heater consists of a metal tube with a high-resistance wire spiral inside it. To ensure good sealing, the components must fit tightly together, so a special insulating material is used.

The consumer must know what materials are included in the construction of the electric heater. Dry heaters with metal fins are made of stainless or carbon steel. For each case an individual variant is suitable, since the working environment is designed for its own parameters of impact on the material. Corrosion resistance is a universal property of the material. For dry heaters, these requirements are low compared to liquid heaters.

  • Different types of heaters can also differ in shape. Dry electric heating elements are only made in straight shape, i.e. к. The anode is placed in a special protective bulb, while conventional heaters can be made in a variety of forms.
  • Conventional electric tube heaters for heating water are installed directly into the liquid. Dry electric heating elements are enclosed in a sealed tube which prevents the heater from coming into direct contact with the medium being heated.
  • Conventional electric heaters are equipped with a magnesium anode to prevent fouling inside the tank. When using dry heating elements, the anode is placed in the tank through a specially provided hole.
  • Dry heaters can only be fitted to boilers with a capacity greater than 50 liters. Due to their size, they cannot be installed in smaller containers.

Peculiarities of flexible dry heaters design

Flexible heaters are designed for high-tech heating of certain media. The main difference between them and standard heating elements is that they can be given absolutely any shape without using any tools. Their flexibility does not affect the performance of the heater in any way. Such heating elements fully compete in their properties and power with standard models, including liquid devices. Flexible heating elements are mostly used for heating molds and hot runners.

Dry heating rods can be made in a wide range. Depending on the design and fixture material, they can be used in different media. The contact rod can be of different lengths up to 60 cm. It is this value that determines the scope of use of the heating element. Based on the characteristics of the environment that requires heating and the location of installation are chosen heater size and certain properties.

Different tube diameters can be manufactured. Different models of electric heaters with different power determines the speed of reaching the operating temperature. Dry heating elements with a power of 2 kW for 380 volts are in high demand. Devices from 40 centimeters long can be connected to 220 volts. Other types of heaters with a range of power from 0.2 to 10 kW are also in demand.

Peculiarities of installation of dry heating elements

  • Installation and fixation is done by mechanical means, which can be clamps, sleeves, clamps and brackets. The method of attachment by soldering is not excluded, but it should be performed with caution. It is important to maintain a distance of 50 millimeters between the soldering points from the end of the heating element.
  • Flexible dry heating elements are usually fixed with a special adhesive solution or mechanically by placing the heater in specially provided grooves.

Service Features

  • Manufacturers try to produce the highest quality heaters, which have high protective properties for operation in a liquid environment. But, it is important to understand that timely maintenance of the equipment greatly prolongs the performance of any heating device. Heated surfaces should be cleaned regularly from possible contaminants. Service intervals depend on the working environment and the rate of contamination.
  • It is necessary to use a protective lubricant in the places of contact of the heating element. Before starting the equipment, you need to remove preservative grease, which interferes with optimal heat output.

Weaknesses of dry heaters

Which heater to choose is up to the consumer to decide. After all, each of them has its own advantages and disadvantages. If you can not decide for yourself the right option: dry or wet heating elements? Experts “Polimernagrev” gladly help you to solve this problem and will conduct a full calculation of the right device for your equipment and environment.

Dry heating element in the boiler

Accumulation water heaters. There are boilers in almost every house. There are two types of heating elements for heating water. immersion and dry. The first type is directly immersed in water, and heating occurs by contact. Dry heating element in the boiler is a spiral, placed in a ceramic shell. The dry heating element is installed in the bulb of the water heater, and the water is heated indirectly. Often immersion heaters fail because of the large amount of scale on the heating element corrosion formation, as well as depressurization and leaks in the contact group. Not infrequent cases of electric shock, so immersion heaters require constant monitoring and frequent replacement.

Advantages of dry heating elements for storage water heaters

When buying a boiler, most are guided by the cost of equipment. But the slight difference in price is paid off by the durability and ease of operation of the “dry” equipment.

Boilers with dry heating elements are guaranteed for several years and have a number of advantages:

  • No limescale on the heating element itself. Limescale is known to form due to the hardness of the water. Dry heaters do not come in direct contact with water and there are no problems.
  • Submersible heating element for the boiler is subject to a significant disadvantage. If plugged in without water the unit will burn out. The dry type has thermal protection and is not afraid of empty containers.
  • If a malfunction is detected, it is not necessary to completely empty the water from the tank. Heating element is removed from the flange tube and repaired or replaced.
  • Often immersion heaters in tanks create air s, which leads to equipment failure. Dry ceramic heating element for the boiler, on the contrary, prevent the formation of voids, and the boiler lasts much longer.
  • The dimensions of the “dry” one are much smaller. If desired, you can install two heaters in one tank.
  • The technology of “dry” heating is electrically safe, the bulb, inside which the dry heating element is located, is in direct contact with water and has a high tightness.

Given the fact that the “dry” heating element has no direct contact with water because of the sealed metal tube, the temperature of the device is much higher than water. Overheating is possible but only if there is a lot of limescale in the tank and on the tube. Cases of complete failure of boilers with a “dry” heating element are rare, since mostly two devices are installed.

Quality guarantee from “Polymer Heating”

All the advantages of “dry” heaters are obvious. Buy a dry heating element in the boiler is available for such manufacturers as Drazice, Bosch, Gorenje, Atlantic, Indesit and others. Our company produces TEHNs according to individual orders, taking into account the parameters of the tank, the area of the room, the power of electrical wiring.

Structure of the dry heating element

The main reason for the increasing popularity of dry elements is the fight against the accumulation of water heater scale. The coil of the device is in a sealed tube and does not interact with water. The construction also uses a dense insulating material.

This technology does not solve the problem of scale definitively. Scale still eventually forms around the bulb, but it accumulates there much less than in models with a classic tubular heater.

To cope with clogging and corrosion of the heating element, as well as the walls of the boiler helps magnesium anode. It is installed by the manufacturer in almost all models. The part is connected so that the tank body and the heating element is already acting as a cathode.

The anode has a negative charge and attracts microparticles to its body, that is, it takes the hit. Therefore it is recommended to change a magnesium anode not less than once in 3 years. You can do it yourself if you follow the safety precautions.

Salt and calcium accumulate faster on conventional heaters. It is covered with a “shell” and after some time burns out in it.

If when heating water from the tank you hear a characteristic hiss, it means that the heating element is already covered with a thick layer of scale and it must be cleaned or replaced.

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Dry heater shape can only be straight. Because of this, it can not be installed in a storage tank with a volume of less than 50 liters.

Types of dry heater

The equipment is classified according to several features. One is the presence of oil in the bulbs. Lubricant has a high conductivity of heat and helps to save the energy of the user of the heating element.

Other models have air or sand between the coil and the capsule. Such a heating element is cheaper and easier to maintain.

The devices also differ from each other according to the required incoming voltage. Some elements run on 380 volts, but in the domestic water heater is used a standardized version that runs on 220 volts.

Another distinguishing parameter is the power. It affects how long it takes for the water in the tank to warm up to the temperature set by the user. The average power of a dry tube heater is 1,200 watts. In wet elements, this figure is usually higher. about two kilowatts.

Differences from the boiler with a wet heater

The wet heater differs from the dry heater in many ways. The main distinguishing features of this part are the way it works and the fact that it is immersed in water inside the boiler. In the same dry heaters, as has already been said, the heating element is in a protective vessel, not in contact with the aqueous medium.

Wet heaters cost less. As a rule, they are installed in boilers of the budget class. Dry elements, on the other hand, are more expensive and are installed in more reliable and expensive units.

Another difference between the wet and dry heater is that in the first version, when replacing the water from the tank must necessarily be drained. In the case of a dry heater this is not necessary at all.

Units with a dry heater are more compact in size than units with a wet element. over, in expensive devices are often installed at once 2 dry heaters, so they heat water much faster.

Also, the difference between dry and wet heaters is that the first are much more likely to burn, failing. Parts must often be replaced in the course of operation of a dry heater.


Dry heaters can seem to last forever, because the parts do not come into contact with water during their operation. But the truth is that things are a little different. You have to take into account that electrical surges and stray currents do destroy the heating element over time. For this reason, boilers of this type have not only advantages, but also a number of disadvantages.

To begin with, we should consider the pros of devices with a dry heater:

  • All the components of the structure in such units last much longer than in simple water heaters.
  • Devices with a dry heater heat the liquid quickly.
  • To replace the heating element, you do not need to drain the water unnecessarily.
  • Such units are distinguished by the absence of scale buildup.
  • Typically, these water heaters have compact size. Thanks to this feature, 2 elements can be placed in one tank at the same time, and water heating is accelerated even more.
  • These varieties of water heaters do not need to be cleaned often.
  • The water quality in these units can be nearly any.
  • Such devices do not have air s.
  • In such water heaters the heater has a high level of protection.
  • In the use of water heaters with dry heater is considered the safest. an electric shock in this case is reduced to zero.
  • Dry heaters are characterized by a good interchangeability. Such designs are suitable for different types of tanks. Wet heaters can not boast such qualities.

Of course, much depends not only on the water heater with a dry heater, but also on the manufacturer that produced it.

Experts strongly recommend buying only quality models from proven companies. As a rule, they cost more, but they last longer, which means that they do not give much trouble during their operation.

How to choose

The following criteria are taken into account when purchasing the device:

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  • The size of the body. When installing in the bathroom of a typical apartment, preference is given to horizontal devices. They are mounted under the ceiling, which helps to properly distribute the space of the room.
  • The functionality of the device. You should not give up on modern technology. Boilers with an electronic control unit and display are equipped with self-diagnostic and cleaning functions.
  • Reliability of the manufacturer. Devices of proven brands last longer than devices of dubious brands. When choosing a water heater, take into account the reviews of users.

Good user reviews have devices of the following brands:

  • “Garanterm”. The company has been manufacturing water heaters for over 25 years. It offers modern devices, corresponding to the world requirements. The main advantage of the products is the low price.
  • Timberk. The international corporation has created a series of boilers, distinguished by a stylish appearance, reliability, durability.
  • Haier. The Chinese company began producing heaters recently. The devices have a low price, average build quality.
  • Ariston. The Italian company has offices in all countries. It produces heating equipment: boilers, boilers, heaters.
  • Hyundai. South Korean company produces not only cars, but also heating equipment. Household appliances are characterized by reliability, versatility, ease of operation.

Good performance have also devices and some other brands, such as Gorenje or Thermex.



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