You want to replace your iron, shabby heated towel rail with something modern, beautiful and functional. So all heated towel rails, or as they are otherwise called design radiators, are divided into water, electric and combined.
We do not need to explain to anyone what design radiators are – the name speaks for itself. These are perhaps the most beautiful heating devices of all. They are distinguished by a wide variety of shapes and colors. Their appearance on the western market is associated primarily with the increasing level of requirements for the design of apartments and offices, both in terms of aesthetics and comfort. As a result, there was a need for heating devices that would be at the same time interior elements. The main manufacturers of such devices are Arbonia, Zehnder, Kermi. In Europe, you can count another two dozen enterprises that manufacture similar products. In Russia, design radiators have been sold for a long time, but they have not received such widespread use as in the west. Russians feel the urgent need for such heating devices so far only in bathrooms. And they even gave their name to design radiators – heated towel rails. By analogy with the domestic U-shaped heating device, which has been installed in our bathrooms for many years. And so, a person gets a new home, looks in the bathroom at the arch sticking out of the wall that has already set the teeth on edge and thinks: Yes, I saw this in the old apartment for many years. It ought to be replaced with something better! And he begins to be interested in ways of solving this seemingly simple question at first glance..
What design radiators the modern market offers to the buyer?
The modern market offers a huge selection. When choosing an imported heated towel rail, one must take into account that most of them are designed for their western operating conditions. To begin with, at least with the fact that our heated towel rail is installed in the hot water supply system (DHW). Do not be surprised, towel warmers in Russia are connected only to the hot water supply system, and not to the heating system, as in the rest of the world. This is another national feature of our heating system..
And who in the DHW system will carry out special water treatment? And thin-walled steel (1-1.25 mm), unprotected from corrosion, is used for the manufacture of these devices. And therefore, in our conditions, these devices do not last long – their service life ranges from one and a half months to one and a half years (a device that has served for 3 years is simply considered a record holder). And an excellent (by design) heating device, which has a rather high cost (from $ 200 to $ 4000 !!!), has to be thrown into the trash after this period, no matter how offensive it is. It can no longer be repaired. And almost 100% of the installed devices are thrown away. Come on, only the device itself would have to be replaced. After the flood, parquet floors, ceilings and wallpaper have to be changed. And partly furniture. And not only in my own apartment, but also in neighbors. And this already smells far from two hundred dollars.
And this is the main reason that Western design radiators have actually discredited themselves in the eyes of the domestic consumer. As a result, the deliveries of imported design radiators to Russia were almost completely stopped. If such radiators are supplied, then they are written in large letters: For heating systems only. That is, for those systems where the parameters of the coolant are more or less acceptable for Western devices (although in fact, these conditions can be called acceptable with a big stretch).
And what are the ways to solve this issue?
There are two ways.
The first of them is to make heated towel rails, designed specifically for our operating conditions. The first attempt to develop and manufacture a heated towel rail for bathrooms, adapted to our conditions, was made by TIME together with the KZTO plant (Tver). We followed a simple path – increasing the thickness of the pipe wall, as well as applying an internal anti-corrosion coating made of polymer material. This design allows you to solve two issues at once: the first is the fight against corrosion, the second is to prevent the accumulation of corrosion products in the heated towel rail. This is how several series of heated towel rails appeared. By design, these heated towel rails are not inferior to the best European models, and in terms of reliability and durability they significantly surpass them. These are models of heated towel rails – radiators in vertical design: “NOTA-18”, “ETUD-9”, “ETUD-18,” “ETUD-24”, “LIRA”.
The production company TVEK has released its model “TVEK-PS-2P”. Created several series of heated towel rails have shown themselves very well. However, creating new series of heated towel rails, we clearly understood that this path (increasing the wall thickness and anti-corrosion treatment from the inside of the radiator) will sooner or later lead to a very high price of the product. Metal is constantly getting more expensive. The technology of working with a thick-walled pipe is already more expensive in itself than with a thin-walled one. Plastic coating on the inner surface is also expensive. And, therefore, this path is dead-end. Moreover, the West has long laid out everything on the shelves – they also walked this path, but did not follow it. Therefore, an attempt was made to solve the problem from the other side – to create a heat exchanger – heated towel rail system.
More precisely, this is the task of dividing the system into two circuits: one remains in the DHW system, the second – the most vulnerable (which includes a heated towel rail) – is removed from the DHW system and thereby increase its life. The challenge was to make the heat exchanger reasonably efficient, maintenance-free, extremely reliable and, importantly, inexpensive. But it should not be a universal, but a specialized heat exchanger, that is, intended only for use in conjunction with a heated towel rail. It was his specialization that helped to solve the problem. Such a heat exchanger has been created. And he even got his own name – TVEK. True, we often call it not a heat exchanger, but an adapter. That is, a device that allows you to adapt the heated towel rail to our operating conditions. Hot water of the DHW system circulates along the first circuit, which is the inner surface of a seamless steel pipe.
The second circuit provides natural gravitational circulation of the coolant in the design radiator. Moreover, the design with a small volume of the adapter itself allows you to get very effective circulation in the second circuit. The average temperature of a heated towel rail is known to be determined by the temperature of the heating medium at the inlet, the design of the heat exchanger and the heated towel rail, as well as the design of the pipelines. In our case, with a nominal power of a heated towel rail of about 600 W, a pipe length of no more than 3 meters from the adapter to a heated towel rail, and at a temperature in the hot water system of 65 ° C, the heated towel rail reaches an average temperature of 55 ° C within 15-20 minutes after switching on. Increasing the length of the pipelines by 1 meter will reduce the average temperature by less than 1 degree. It’s not scary either.
The average temperature of the heated towel rail is 10 ° C lower than the temperature of the water in the DHW system. And the bathroom won’t be cold as a result?
Rather the opposite. The area of a standard U-shaped heated towel rail is extremely small (which is why high temperature water is used to heat it). We have replaced the small U-shaped knee with a heated towel rail with a large ramified surface. And this means that much more heat will be released into the air. You will also have to install a valve that limits the flow of coolant.
How reliable is such a device?
Thermal tests carried out at the Research Institute of SANITARY TECHNOLOGY have proven the absolute performance of the system. As for the strength and, consequently, the reliability of the adapter itself, it is primarily determined by the design of the primary circuit of the heat exchanger, which is connected directly to the DHW system. And this circuit is made of a thick-walled solid-drawn steel pipe, the reliability of which has already been proven many times in a variety of products (including heated towel rails installed in our bathrooms during serial construction).
It depends only on the quality of the original pipe. So if you use a good pipe produced by a good manufacturer, then there is simply no need to doubt the strength characteristics. And 20-30 years of work for such an adapter are guaranteed. This is confirmed by the tests that the TVEK adapter has already successfully passed. Applied technical solutions are patented.
How much does the use of the adapter increase the cost of the design??
Installing an adapter will not increase the cost of the system much. Basically, the cost of the adapter itself and the cost of installing it into the system. Thus, the rise in the cost of the system is possible within 5-10%. But the system with the adapter has an imperceptible at first glance, but a very big plus, which justifies such a rise in price. If earlier, when laying the pipeline, you had to take into account the pressure in the system, and the presence of oxygen in the hot water system, and the possibility of water hammer, etc. and therefore the pipeline had to be sufficiently rigid and durable, then with the use of an adapter, a rigid pipeline remains only in the first circuit. In the second circuit, you can use any pipes – plastic and metal-plastic, flexible, etc. (This, incidentally, also provides additional design opportunities). And in such a system, there simply cannot be major accidents. If you have poured an excess amount of coolant into the second circuit, then it will not burst when heated, because the safety valve in it will simply dump the extra grams of water. And even if for some reason the underwater pipe of the heated towel rail bursts, your neighbors will not even notice it – the volume of the coolant in the second circuit of the system is only a few liters. This is not 50 cubic meters of hot water, which are thrown into an apartment in the event of an accident in the supply pipeline in the existing system..
Now, together with the Kermi plant, a whole family of design radiators with a TVEK heat exchanger is being prepared for release, which will soon appear on sale. The real working resource of the system will be at least 20 – 30 years. In addition to the problem of strength and corrosion in devices for hot water supply (DHW) systems, the internal section of pipes is actively overgrown with deposits, sometimes until the channels are completely blocked. When using heat exchangers, this problem is easily solved by cleaning the primary circuit of the heat exchanger or replacing it. Naturally, such a procedure is much cheaper than replacing the design radiator itself..
Electric towel warmers are good in three cases:
In addition, do not forget about long summer blackouts of hot water. An electric heated towel rail is easy to install and connect without a grand alteration of all pipes in the apartment. When installing an electric heated towel rail, you must strictly follow the rules and recommendations of the PUE. The choice of electric heated towel rails in the TIME company is quite wide. Almost all Russian water heated towel rails ETUD, LIRA are produced in electric version.
The selection of electric heated towel rails (design radiators) of the German company ZEHNDER is especially wide. All of them have a programmer, which allows you to set comfortable living conditions. The ARBONIA design radiator has manual adjustment.