Heating elements for heating radiators: purpose, types, selection criteria, connection features
With the onset of cold weather, the issue of home heating becomes more pressing.In the chilly off-season, centralized systems are often not turned on until the last minute, and then alternative heating systems come to the aid of freezing residents.
One of the simple solutions are considered to be heating elements for heating radiators, which can become an effective addition to the heating system. In some situations, the device can easily cope with the role of the main heat source, for example, in seasonal premises.
Before you decide to buy a device, you need to find out more information about it, don’t you agree? We have prepared a review article about the design of radiator heating elements, their classification, advantages and disadvantages. The material identifies the main criteria for choosing an electrical appliance and describes the features of its installation.
The content of the article:
Heating element for a radiator: why is it needed?
Like any other heating element for heating, a radiator is designed to heat the coolant and maintain its operating temperature. The device can be installed in almost any heating device that has an internal cavity filled with liquid. Thanks to this, its scope of application is quite wide.
Radiator heating elements can act as the main or additional heating source. They are very good as heat sources for rooms with a relatively small area, which are used periodically during the cold season.
For example, various utility rooms or for garage heating. In this case, the heating element is mounted in an autonomous radiator; it usually has impressive dimensions.
The battery is not connected to the heating system and is filled with coolant, which circulates exclusively within the radiator body.
In such cases, technical oil with a low viscosity is chosen as a coolant, which allows you not to be afraid of the radiator completely freezing during non-working hours. It turns out to be an analogue of an oil-type radiator, only larger in size.
Radiator heating elements have proven themselves quite well as the main source of heat for country houses that are heated periodically. The system is set up similarly to that described above, but only the heating elements are mounted in batteries installed in each room.
It is possible to organize such heating for houses with permanent residence. In this case, the batteries can be filled with ordinary water, since there are no plans to allow the system to freeze. True, such options are used extremely rarely due to the high cost of electricity.
More widely, radiator heating elements are used as additional heat sources. They can be built into an existing heating system with a liquid coolant and come into operation when the main heating is not functioning for some reason.
This solution is especially suitable for houses with centralized heating. During the period when it is turned off, heating elements literally save apartment residents from freezing.
Another good option is to connect devices to an autonomous heating system with solid fuel boiler. This will allow maintaining a comfortable temperature in the rooms even at times when the owner is not able to supply fuel on time.
If it is possible to use a multi-tariff meter, it may be practical to switch to night heating with electricity when it is relatively cheap. During the day the boiler will start working again.
Practice shows that it is not economically profitable to use radiator heating elements as an additional heat source for autonomous systems running on gas. This type of fuel itself is relatively cheap, so replacing it with more expensive electricity does not make sense.
If used indoors liquefied gas boilers or on diesel fuel, the benefits will be obvious. But only if you have a two-phase electricity meter.
How does an electrical appliance work?
The design of the device is practically no different from other types of heating elements. The body of a tubular electric heater is made of a seamless or electric-welded thin-walled metal tube. Its diameter can vary, and its cross-section can be flat or round.
Carbon steel is most often used as the material for the manufacture of the case, but stainless steel can also be chosen if the working surface of the device will be heated to temperatures above +45°C.
To protect the metal from corrosion and extend the service life of the heating element itself, the steel body is chrome or nickel plated. A spiral of nichrome wire is used as a heating element.
The element has a high resistivity, due to which it heats up quickly. The spiral is placed inside the body, and the remaining free internal cavity contains filler.
The housing has high electrical insulating properties and at the same time transfers heat well. Purified quartz sand or periclase can be used as a filler - this is the name of a mixture of crystalline magnesium oxides.
After the body is filled with filler, it is pressed and bent to give the required shape. All insulators are coated with an organosilicon moisture-proofing compound.
Such a device can be installed in radiator of any type: copper, cast iron, bimetallic, etc. The device is capable of generating up to 2.5 kW of power. Models intended for industrial use produce up to 6 kW.
The design of the electric heating element is such that the device completely converts all incoming electrical energy into heat, with virtually no losses.
The operating principle of the device is extremely simple. When activated, it begins to heat up quickly, warming up the coolant located in its immediate vicinity. According to the laws of physics, a heated liquid is lighter than a cold liquid, so it begins to move upward.
A cooler coolant is lowered in its place.Having risen to the top of the radiator, the heated liquid gives off its heat there, cools down and falls down.
The cycle is repeated many times. Thus, the electrical device creates a unidirectional flow of liquid inside the battery. The higher the power of the device, the higher its speed.
Based on practice, transformer oil is considered one of the best types of coolant. The liquid heats up quickly and does not cool down for a long time, gradually giving up its heat to the radiator body.
Pros and cons of radiator heating elements
Tubular-type electric heaters make it possible to assemble a practical and fairly efficient heating system for main or additional heating.
The advantages of the devices include:
- Extreme ease of installation. Every novice master can handle this job.
- Low cost of the deviceHowever, this refers to the price of one heating element, without additional equipment.
- Greater reliability compared with oil radiators. In addition, batteries with heating elements are repairable. If the equipment fails, it will be enough to replace the heater.
- Availability of additional options and functionality.
- Possibility of automatic control heating system, but this will require additional equipment.
We have listed the main advantages of radiator heating elements; we will consider their significant disadvantages. There are quite a lot of them. First of all, these are impressive operating costs, which is explained by the high cost of electricity.They can be reduced if the heating system control is fully automated.
In this case, the heating elements will be switched on only after the room temperature drops to a certain minimum value. And turn off when the temperature defined as comfortable is reached. Working in this mode is as economical as possible.
However, automation equipment will require financial investment. If we consider purchasing a heating element complete with a radiator and automation, the cost of such a kit will be much higher than the price of an electric convector or an oil radiator.
But at the same time, in terms of the level of comfort provided, the latter are in no way inferior, and in some ways even superior to radiators with heating elements. For example, the latter require permanent installation, while electric convectors and oil radiators are more mobile and compact.
In addition, like any other electrical device, heating elements generate a magnetic field during operation. Its danger to the body has not been proven, nor has its safety. Therefore, it is worth attributing the presence of such a field to the negative qualities of devices, because they are mounted in radiators, that is, they are in close proximity to people.
In other heating systems powered by electricity, this disadvantage is to some extent leveled out. For example, electric boilers are located in non-residential premises where human presence is short-term.
One of the most significant disadvantages of radiator heating elements is their relatively low efficiency.If we compare it with the efficiency of traditional systems operating with liquid coolant, it will be significantly lower.
This is due to the fact that in the first case the coolant moves at a fairly high speed. Thanks to this, the radiator warms up quickly and completely.
The functioning of the heating element is not able to provide such a high speed. As a result, the heating of the battery case will be uneven. The temperature at the bottom will be much higher than at the top.
Considering that, for safety reasons, the battery should not be allowed to heat up above +70ºС, such a temperature will only be present in the lower part of the radiator, where the heating element is located. Consequently, in order to prevent overheating of the equipment, it will be necessary to reduce its power by about a third.
Types of tubular heaters for radiators
Despite the simplicity of the design, you can find various variations of radiator heating elements on sale. First of all, the power of heating devices varies. Models with a minimum power “produce” about 0.3 kW, with a maximum – 6 kW.
The devices differ in the design of the housing. Considering that the configuration and location of radiators can be different, there are heating elements with left-hand or right-hand threads.
The diameter of the device may also vary. This is due to the cross-section of the radiator plug plug, in the place of which the device is mounted. Standard size is 40 mm.
There is no fundamental difference between devices intended for installation in radiators made of different materials.Their design is similar, only the diameter may differ. You can find single and double heating elements on sale.
The latter is more convenient to use. At the moment of switching on, both elements are activated at once, due to which the coolant heats up as quickly as possible. After this, one of the elements is turned off, which allows you to save energy resources. Some models are equipped with additional functionality.
The manufacturer uses only two functions:
- Turbo heating. Makes it possible to maximize the increase in temperature in the room. A thermostat is necessarily built into the device, which allows you to change the heating intensity.
- Antifreeze. This mode allows you to prevent possible defrosting of the entire system when the temperature drops to negative values. The heating element automatically maintains the minimum permissible temperature, while consuming a small amount of electricity.
In addition, radiator heaters vary in length and the presence or absence of a thermostat.
How not to make a mistake in choosing
Radiators for heating elements are quite simple to choose, since they do not require a special variety of designs and technical characteristics. Please consider the following points before purchasing.
Electric heating element power calculation
In order to correctly determine the required power of the device, it is advisable to know the thermal standards in force in the given area.As a last resort, you can use the average indicator, which can be used in central Russia and make some adjustments if necessary.
Based on this, for 10 sq. meters of heated area, provided that the heating element will be used as the main heating, 1 kW of its power is required.
If the device is used as additional heating, the required power will be 3-4 times lower. In addition, when choosing a device, you should take into account the specifics of the radiator heating element.
Due to its design features, it will be able to operate uninterruptedly only at 75% of the heat transfer from the radiator. With higher power, the device will overheat and it will constantly turn off.
Based on this, the power of the device is calculated. The exact heat transfer values of a particular radiator can be found in its technical documentation. However, on average, one section of an aluminum battery has a heat output of 180 W, and a cast iron battery has a heat output of 140 W.
Let us calculate, as an example, which heating element is suitable for a 10-section radiator. We multiply the data by 10 and we get that for an aluminum battery it is worth taking a heating element with a power of up to 1.35 kW, for a cast iron battery - up to 1 kW.
Design features of the device
For each radiator, you should select a heating element that is suitable for it in size and thread direction. The equipment has different shaft lengths, which may affect its performance.
If the length of the heating element is insufficient, the equipment is not able to provide a sufficiently high circulation rate of the coolant, as a result of which the heating of the radiator will be uneven and insufficient.
The optimal option is when the heating element rod does not reach the inner wall of the opposite edge of the radiator by 60-100 mm. It is also important to choose the right body shape and diameter of the device.
The material of the plug may vary between models. To make the right choice, you should study the manufacturer’s recommendations, where he describes the types of heating devices suitable for using a particular heating element.
Availability of automatic control
Devices are available for sale with or without built-in automatic control. The first variation is as convenient as possible and does not require the purchase of additional equipment. In this case, a thermostat with a sensor that measures the temperature of the coolant is built into the lower part of the heating element housing.
If there is no built-in automation, the electrical appliance does not have a thermostat. In this case, it is advisable to connect using a detector that measures the air temperature in the room.
It must be admitted that this equipment is not so popular and in demand for large European companies to start producing it.
In stores you can find radiator heating elements made by Turkish, Polish and Ukrainian brands. In terms of quality and functionality, they are approximately similar.
It is difficult to say which company's products should be preferred.But you need to be wary of Chinese heating elements, since you can often get a low-quality product.
Additional information on choosing a heating element for heating is provided in this article.
Features of installation of radiator heating elements
Installing the device is quite simple. In order for the operation to take place without any difficulties, you should familiarize yourself with its equipment in the store. Ideally, together with the heating element, all the elements and fasteners necessary for a safe connection will be placed in the box. If any parts are missing, you need to purchase them immediately.
Another important point: before starting installation, you should make sure that the system is free of water. For this reason, in apartment buildings it is optimal to carry out work in the summer, when the central heating is turned off.
The actual installation consists of removing the plug located at the bottom of the radiator and then installing a heating device in its place. To make the joint airtight, a rubber gasket must be installed. It would not be superfluous to pre-treat the joint area with sealant.
The heating element can only be installed in the lower part of the radiator so that liquid circulation can occur unhindered. The part is inserted into the battery strictly horizontally, otherwise problems with operation may occur.
To connect the heating element it is allowed to use socket with grounding. It is advisable to install a voltage stabilizer to protect the device from network surges.
You can connect the device to the network only after filling the radiator with liquid, otherwise the device will fail. The design with a heating element is repairable. If necessary, the device can be easily removed and repaired, and more often replaced with a new one.
Considering the hardness of process water, experts recommend regularly descaling the heater. To do this, the device is removed from the battery, after which it is cleaned.
You can use a mechanical method, when the scale is carefully removed with sandpaper or a stiff metal brush. This should be done very carefully, since heating elements are very sensitive to mechanical damage and can fail.
In addition, you can use the chemical method. In this case, the device is treated with special substances. It is very important not to damage the rubber gasket.
Conclusions and useful video on the topic
The videos provide rational advice on the use and connection of heating devices.
How to install a heating element into a radiator yourself:
We offer an overview of the heater for a cast iron radiator:
Heating element for aluminum radiator:
Radiator electric heating elements are a good way to provide additional heating for rooms for a wide variety of purposes. They are relevant for cottages, garages and buildings used from time to time.
Such heating elements are rarely recommended as the main heating. Still, they consume quite a lot of electricity, so you can find another, less expensive way to heat your home.
Are you looking for an effective device for organizing additional heating? Or do you have experience using radiator heating elements? Please leave comments and ask questions on the topic. The communication block is located below.
I installed this type of heating at the dacha, since there is no gas in the village and is not expected in the coming years, and heating with wood is troublesome. I installed heating elements with thermostats in aluminum radiators. And, by and large, that’s it, no problems.
I chose aluminum radiators because they have better heat transfer than cast iron ones, and they look more modern. There is no need to paint them, just wipe them from dust with a damp cloth. When installing, you only need to select the heating elements correctly in terms of power and length, and install them carefully, there is electricity after all.
I took the power with reserve so as not to freeze. I’ve been using it for three years now, I haven’t identified any problems yet, I haven’t taken out the heating elements or cleaned them, I think I’ll do this in about two years. The only negative is electricity bills, which are more expensive than gas, but cheaper than wood. The advantage is that you can regulate the temperature yourself, but with wood you can’t do that.
Sergey, how much more expensive is gas heating and how much cheaper is firewood?
To be honest, using heating elements in a central heating system is a waste of money. I can still approve such a decision for a private house, but not for apartment buildings.
Regarding your question: it is difficult to give exact figures, since there is no data on the area of the house, local electricity tariffs, etc. But I can immediately say that heating a private house with electricity will be more expensive than other options: gas, wood, coal.But you can significantly reduce heating costs with electricity if you agree on a project for heating your home exclusively using this energy source. In addition, the use of a two-zone day/night meter will further reduce heating costs.
Combined heating systems gas + heating elements in radiators or solid fuel boiler + heating elements are unprofitable. In apartment buildings, even more so, since water is heated from the entire heating system, and besides, its hardness and impurities will not give the heating element a chance to work for more than one season.
If you connect it to a solar battery, then that’s another option. And steam-drip heating is better, either from solar collectors or from the central power grid.
If this does not work, then as a last resort, assemble a lithium battery and charge it at night at the night rate, and switch to it during the day. Of course, Russia has plenty of energy resources, but they want to get rich by selling it to the people. Therefore, it is necessary to switch to alternative sources.
Plus, build bunkers, it’s warmer and cheaper in the ground, at the dacha there is a pit for the entire territory and 4 underground houses on 6 acres, and so on. You can’t build security anywhere near the surface. Drill more water closer from the bunker. Sow potatoes on top, build a house from a light steel profile. So a dacha near Moscow or London for 4 owners may turn out cheaper.