For decades, electric heating elements have not changed their design and remain in demand in heating equipment. The form of these devices, constructive materials is changing, but the principle of operation and efficiency remains unchanged. For proper selection of useful information about the differences and characteristics. Do you agree?
You will learn what are the heating elements and how they work for heating. We described in detail the varieties of heating elements, gave indisputable arguments for the informed choice of the optimal type. Taking into account our recommendations, you will get the required device without errors.
The content of the article:
- Purpose of heating TENOV
- Internal device of electric heaters
- The principle of operation of the heating elements
Types of heating elements for heating devices
- Tubular models for domestic heating
- Ribbed Electric Heaters
- Block designs of heaters
- Cartridge type devices
- Additional functions of electric heaters
How to choose heating elements for heating equipment?
- Power calculation
- Consideration of design features
- Heating tube length
- Availability of additional functionality
- Conclusions and useful video on the topic
Purpose of heating TENOV
Electric TENY gained popularity due to its versatility and high efficiency. All electricity consumed by them is spent for its intended purpose - for heating the surrounding space.
The main heating devices that use heating elements are:
- Portable and stationary oil heaters.
- Water heating radiators.
- Towel rails for the bathroom.
- Electric boilers.
The specified equipment can be used as the main or additional source of heating. It is inexpensive, easy to install and does not require special skills during operation.
It is possible to connect the heating element to the cast-iron radiator of the central heating after disconnecting the common riser. This device can be used for primary and secondary heating.
Internal device of electric heaters
The device is convenient to consider the example of a tubular model. The electric heater is a ceramic or metal tube filled with a thermal conductor with a spiral located inside. In the place of fixation of the tube to the flange there are insulating sleeves that make it impossible to contact the conductive coil with the body of the heating element.
Most models of heaters use similar components, but their durability may differ depending on the build quality.
The electric heater is fixed mainly by a flange joint, which allows sealing the internal environment of the heater from external space. The disadvantage of this design is the impossibility of replacing the spiral with its internal burnout.
The principle of operation of the heating elements
The heating element works according to the following principle. When connected to the network, the internal spiral heats up and energy is transferred to the thermal conductor and the outer shell. Subsequently, heat is transferred to the surrounding fluid, air, or solid material.
When heating a heating element immersed in oil or water, convection currents are created around the tube, which mix the heat transfer medium and contribute to its uniform heating.
Electric boilers are known for their reliability and maintainability. They do not have many complex parts, so they are easy to operate and maintain.
In non-liquid heaters, the heating temperature is usually limited so as not to damage the surrounding parts and not cause a fire.
To speed up heat exchange, they often use a fan that circulates air both inside the device and in the room around it.
Types of heating elements for heating devices
The simplicity of making heaters does not always turn into user convenience. Many manufacturers produce electric heaters with a specific shape and fastening. In the event of a breakdown they are quite difficult to buy in the store. Therefore, for the correct choice, it is necessary to explore all possible design options.
Tubular models for domestic heating
The tubular design of electric heaters is the most common in mobile oil heatersportable and wall mounted electric radiators. The transfer of heat in them can occur through: convection, infrared radiation or heat conduction.
Finished heating elements with a regulator and its own power cord can be bought only if you are certain that the length of the wire will be enough
The shape and length of the tube in such devices can be any and is dictated only by design features. For example, TEN mikatremichesky heater is a coil, located behind the mineral plate. When heated, the plate radiates infrared heat.
The most common are its characteristics:
- diameter - 5-18 mm;
- length - 200-6000 mm;
- shell material - steel, stainless steel, ceramics, copper;
- power - 0.3-2.5 kW.
TENY with a capacity of more than 2.5 kW in household heating devices do not apply, because apartment wiring simply will not withstand a greater load.
Ribbed Electric Heaters
Finned devices are a modification of tubular heating elements. Their feature is the presence of many thin steel plates located along the entire length of the device. This design dramatically increases the area of contact with the environment, providing a high rate of its heating.
Finned heating elements are more expensive, demanding to the volume of working space, but provide higher consumer characteristics of heating equipment
Finned models are used mainly in heaters for air heating. They provide a rapid increase in temperature in the room, especially with an integrated fan.
Block designs of heaters
The block variant is a combination of tubular heaters combined on the basis of a single mounting.
Special attention should be paid to the capacity and ability of the boiler with a pump to ensure heat removal when choosing block TENs.
This design is used when combining two factors:
- The need for increased instrument power and high heating rate of the working medium.
- The impossibility of the rapid transfer of thermal energy from the spiral to the environment due to the small area of the outer shell.
In fact, in the block TENE, the load on each heating tube is reduced and the rate of heat transfer increases. Such devices are part of domestic heating boilers and industrial electric heaters.
The power of block models can be 5-10 kW, so when they are placed in an apartment, an additional electric cable must be pulled into the room.
Cartridge type devices
Cartridge heaters have the form of a tube with one free end, due to the peculiarity of their installation. The outer shell is usually made of polished steel to ensure maximum contact with the surrounding material. Such tubes are tightly inserted into the corresponding opening of the heater.
The main drawback of cartridge heaters is the small area of the heat transfer surface, which requires the use of specific methods for the removal of thermal energy
Fixing of cartridge models is carried out mainly by means of a flange connection. They are usually used in industry for heating the working parts of extruders.
There are other structural types of heating elements, but they are mainly used in industrial production and do not affect the subject under consideration.
Additional functions of electric heaters
Above were considered the simplest design of devices that do not have any built-in adjusting mechanisms.
The thermoregulation unit can be mechanical or electronic. The latter is more accurate, but demanding on the parameters of the home power grid
But electric water heaters can be equipped with the simplest automation, providing additional functions to the device.
- Thermoregulation. Heating elements with a built-in thermostat for heating have a temperature sensor that is triggered when the working medium is heated to a certain level. Adjustment of the electric heater occurs on the outside of the flange.
- Anti-freezing. This function is provided by a simplified thermostat that only works when the temperature drops to 0-2 ° C. It prevents water from freezing in the heating pipes, consuming a minimum of electricity.
- Turboheating, which provides forced heating of the working environment during the initial start-up of the equipment. It must be remembered that the wiring of the room must withstand a brief increase in power.
There are not so many devices supporting additional functions, because often the regulation of the operation of heaters as a whole is carried out with the help of a separate automation unit.
How to choose heating elements for heating equipment?
Choosing TEN for replacement in a water heater or in the radiator, it is necessary to pay attention to its power, design, length of the tube and the presence of additional features. Therefore, before buying you need to know as much as possible about all its characteristics.
High power heaters are not always a positive quality.
When choosing it is important to consider several factors that are related to the level of energy consumption:
- extreme heat output power of the heater as a whole;
- wiring possibilities;
- volume of the room.
You can not buy a device with a power that is more than 75% of the maximum level of heat transfer heating equipment.
For example, there is a radiator with 10 sections, each of which gives 150 W of heat to the air, only 1.5 kW. When installing an electric heater with a power of 2 kW, the surface of the battery will not be able to quickly give up all the generated energy. As a result, the heating element will be constantly disconnected due to overheating.
The reason for the rapid breakdown of the heater can be the wrong choice of power device. As a result of the system overheating of the spiral, it eventually burns out
In apartments with worn wiring a constant load on the outlet should not exceed 1.5-2 kW, otherwise it can catch fire and lead to sad consequences. Therefore, before purchasing the heating element, you need to check the condition of the wiring and if necessary, dismantle the old and build a new power grid.
When the issue with the electrician and the capabilities of the equipment is resolved, you can begin to calculate the required power to maintain a comfortable temperature in the room.
In well-insulated houses and apartments, a level of 40 W / m will be sufficient.3. And if there are gaps in the windows, the heating power should be increased to 60-80 W / m3. You can buy a specific model only after taking into account all the above described energy factors.
Consideration of design features
Most heating heaters have an alloy steel shell that provides strength and resistance to corrosion. Copper devices are used mainly in water heaters, although there are no restrictions on their use in home-made radiators.
In cast iron and steel radiators, the use of non-ferrous metal heating elements is undesirable. This can lead to accelerated wear of materials and compounds.
Also, when choosing, it is necessary to consider the direction of the thread of the plug, which can be right or left. Different models of electric heaters differ in flange diameter. They can be from 0.5 to 1.25 inches.
Usually a brief instruction is attached to the heating element of a good manufacturer, which describes its design parameters. Their study will help to buy a device that exactly fits the existing heating equipment.
Heating tube length
The length of the tube is one of the main characteristics that determine the efficiency of the device.
Its long length at equal power leads to an increase in the surface area of the electric heater and acceleration of heat exchange with the working medium. This has a positive effect on the durability of heating elements and the rate of circulation of the coolant.
Long-tube heating elements are ideal for installation in home-made registers, which are convenient for heating large rooms and outbuildings.
It is desirable that the tube runs along the entire length of the working area of the heater, without reaching 6-10 cm to the opposite wall. This recommendation allows you to warm up the coolant quickly and evenly.
Availability of additional functionality
Overpaying for additional features of heating elements is not always necessary. If the heater is used as an auxiliary and does not have its own built-in automation, then buying a model with a thermostat makes sense.
But if there are own thermal sensors and temperature control mechanisms in the radiator or electric convector, additional functions will remain unclaimed.
The electronics built into the plug of the heating element must have safety mechanisms so that in case of failure of the control board there is no fire
Therefore, it is recommended to purchase expensive electric heaters with built-in automation only when there is a clear need for such equipment. If necessary, an individual selection of the temperature background is better to buy thermostat in the outletwhich can be used periodically.
As for manufacturers of heaters, their choice is not fundamental. The main suppliers are firms from Russia, Ukraine, Turkey and Italy. The quality of their products is about the same, so it makes no sense to overpay for the brand.
Conclusions and useful video on the topic
Video # 1. Practical overview of various types of heaters:
Video # 2. The review of TENA with a temperature regulator:
Video # 3. Features of the block TENA used in heating electric boilers of heating:
Purchase of heating elements for heating devices is not an easy task. This requires a clear knowledge of the characteristics of the equipment into which the electrical heater is built. Therefore, it is necessary to stop the choice on a specific model only after a thorough analysis of its parameters.
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