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Heated walls. Warm walls - heating system for houses and apartments. Advantages and disadvantages

For some reason there is an opinion that it is not enough efficient system heating. However, it is very popular in some European countries(for example, in Germany), where warm walls heat big number high-rise buildings. It is unlikely that this was done only to speed up the pace of construction... In fact, the heating system with warm walls has many advantages.

Advantages of heating with warm water walls

Warm water walls provide the room with high-quality, i.e., the most favorable heat for people (the word “quality” means radiant heat, which is precisely the most favorable for us).

It makes sense to talk about the merits of something only in comparison with something else. And since we compared warm walls with warm floors above, we will continue their comparison.

The vertical projection of the human body is 23 times smaller than our lateral unfolded surface. That is, in order for us to feel more comfortable standing and sitting even at low air temperatures, radiant heat should be emitted not by the floors, but by the walls! We feel the heat that heated floors provide only due to direct contact of the foot (thermal conduction) and the movement of warm air (convection). And just a little bit of the highest quality and healthiest radiant heat! I think it’s easy to conclude in favor of heating with warm walls.

Another plus is a reduction to a minimum (or complete absence) convective air flows in the room, hence the lack of dust circulation throughout the room.

Unlike heated floors, in heated walls you can use water at a higher temperature (up to 70 degrees), and the temperature difference in the supply and return can reach 15 degrees (in a heated floor 10 degrees maximum). What does this give us? The circulation pump can be used with lower power, which means it will consume less electricity, and the price of such a pump is lower.

The laying step of the wall pipeline is not limited in any way, since temperature differences between adjacent sections of the wall are allowed. And these changes are not felt in any way by a person. That is, fewer pipes will cover the same area as the floor area.

As mentioned above, heating with warm walls saves on energy.

Where do the energy savings come from when heating with warm walls?

It turns out that with this type of heating a person is comfortable even at a lower temperature than if the heating was radiator and the heat was distributed convectively in the room. That is, the air will need to be heated 1.5...2 degrees less (it seems like small numbers, but in the end the energy savings are noticeable: 8...11% of fuel is saved). Well, I already said about the pump...

Diagram of a heating system with warm water walls

Warm walls schematically look like this:

As in a heated floor system, there is a collector (1), and pipeline loops (4) are routed from it along the walls. In diagram 2 - wall cladding, 3 - reflective plates, the task of which is to improve heat transfer and make it uniform.

The only subtlety here: since the loops are located vertically, it is necessary to remove air that can accumulate at the highest points (but more on that later).

Types of water-heated wall designs

Structurally warm walls can be made in two ways: with horizontal pipes:

And with vertical:

With horizontal pipes, it will be easier to remove air from the system.

Thanks to the variable pipe laying pitch, you can achieve the most ideal heat distribution in the room. So, lay pipes at a height of 1.2 m from the floor in increments of 10...15 cm; from 1.2 to 1.8 m from the floor, increase the step to 20...25 cm; above 1.8 m pipe spacing is acceptable 30...40 cm:

The direction of movement of the coolant is taken from the floor to the ceiling, i.e., the most warm areas located at the bottom of the wall.

Since warm walls are sources of radiant energy, they need to be positioned so that they are not then covered by furniture.

It is allowed to heat two adjacent rooms with one loop. That is warm wall make a partition between rooms.

When and where is warm wall heating used?

When there is no free space in the room, due to which underfloor heating will be ineffective (in bathrooms, garages, swimming pools, workshops... so they say, but I would doubt about workshops and garages - and what master doesn’t dream of full-wall shelving ?! Again, judging by myself, perhaps you have different preferences).

When there is little furniture and equipment along the walls in a room (offices, corridors, auditoriums, bedrooms, halls, recreation areas, etc.).

Where there is high floor humidity (bathrooms, laundries, swimming pools, sinks), then the warm floor will not be effective for heating, since a lot of its energy will be spent on evaporating water from the surface.

By the way, nothing prevents you from making a combined heating system from warm walls and heated floors, so that they complement each other if the power of one system is insufficient. For example, the power of a warm floor is not enough - we make warm walls under the windows (not radiators):

Or warm walls + radiators: the warm wall works most of the time, and the radiators are turned on only to quickly warm up the room or during extreme frosts. Another option is to combine all three water heating systems: warm walls + warm floors + radiators. This is if the walls are brick, not insulated, and large heat losses occur through them (to be honest, it’s not clear why install so many systems and then pay for their work, when you can invest once in insulating the house? But everyone goes crazy about to your own).

Design features of the warm water wall system

If the warm wall system is installed on outer wall, then special attention should be paid to the calculation temperature conditions, namely: where and how thick should the insulation be on the walls? When insulating a wall externally, the freezing point shifts into the thickness of the insulation, so non-frost-resistant materials can be used for such walls. The disadvantage of such insulation: in addition to the energy costs for direct heating of the room, energy is spent on warming the wall.

Another option is to have the wall insulated from the inside of the room. Then the freezing point of the wall also shifts inward. But not the insulation, but the wall itself. In this case, you need to use frost-resistant wall materials, otherwise the wall will freeze and condensation will appear (between the wall and the insulation and in the thickness of the wall itself). Operational control of the coolant temperature is also important.

If the walls are not insulated at all, then an erroneous calculation or a delay in temperature regulation can lead to significant heat loss through the external walls. Large heat losses occur due to the large temperature difference between indoor and outdoor air. And large heat losses lead to a large number condensation of moisture from steam entering from the room into the outer wall during diffusion (I believe it is clear that this condensation occurs inside the wall? That is, in severe frost this moisture can freeze, when freezing the water expands - the wall is destroyed; do you need it?).

After calculating heat inflows, you need to consider the following: the warm wall system can be made on interior walls, and, on the one hand:

During this installation, heat is distributed as shown in the figure: 70% in the room where the pipe is laid, 30% in the adjacent room (in the absence of thermal insulation between the rooms). This can be taken into account during design and calculations.

Although structurally water-heated walls are very similar to water-heated floors, there are a number of features here that need to be taken into account during design or installation. So, the water speed in the pipes of warm walls should not be lower than 0.25 m/s (this is calculated in a special program, which we will discuss in other materials). Why? At such and higher speeds, air pockets are “washed out”. If the coolant flow rate is too low, airing of the system is very likely.

In a heated floor system, removing air from the system is achieved quite simply: we install an air vent on the manifold and that’s it.

In warm walls, the highest point of the contour is the upper loop, and this is where air accumulation is most likely. So the air vent on the manifold will not give anything, but this device is installed on the top hinge, which is described in detail in the article about installation.

In heated floors, the pipe can be laid in two ways: snail and snake. The snail is not suitable for warm water walls, because air pockets will not be washed out in it. The conclusion is clear: only a snake!

That, it seems, is all the theory is about, but we’ll talk about practice – about editing – in the section on editing.

warm water walls

Everyone has heard about warm floors. What about warm walls? Heating of walls is not news; just remember what the walls in ancient temples are like. They have one large chimney running in a spiral from the stove. The heat from the source passed through the long chimney tunnel and heated the wall, releasing heat inside.

Modern warm walls would help solve a number of heating issues:

Cut off the cold from the street.
Get rid of convection by eliminating traditional heating radiators, which means eliminating dust in the air.
Increase the heating area, correspondingly reduce the temperature of the heated surface and make the heating process uniform and more comfortable for the inhabitants of the house.

However, if you make a warm wall traditional way, then there is a high probability of damage during the repair process. Judge for yourself, how to hang a shelf and not damage the tube through which the coolant flows?

If you do electrical heating of the walls, then the core can still be found using special device, however, dust attracted by the electromagnetic field will create a muddy pattern on the walls, which, you see, will not be very pleasing to the eye.

The 3THERMO company has found a way out of this difficult situation. The company's engineers designed the radiators in such a way that the coolant flows only in the lower part, and since the radiators are made of aluminum alloys, which have good thermal conductivity, the heat spreads throughout the entire wall. The mesh from which the radiator is made plays the role of reinforcement for the plaster applied to it. This heating system is installed before applying plaster to the walls. Due to the large area of the radiator and its low temperature, special compounds for leveling the walls are not required. During operation, the plaster will not crack, the manufacturer of radiators for warm walls promises.

If desired, such a radiator can be placed in a horizontal plane, then it will turn out to be an analogue of the warm floor that is so familiar to us.

Such radiators are connected in series using a special rubber hose. It has a reinforced design, while remaining quite flexible, which is important for passing corners, where a small bend radius without refraction plays a role, this will significantly save on fittings. The rubber hose can withstand high temperatures, so if the heating system fails, nothing will happen to it, even at temperatures of 120°C.

The hose is fixed with special clamps using pliers. It's quite fast and easy. In general, the design is very simple to install.

After plastering, we get walls without unnecessary protrusions. Below is a video of this system, although in Polish.

Photo: 3THERMO
Text: Varvara Ilitskaya

Wall-mounted water heating has a number of undeniable advantages compared to other methods of transferring heat into a room.

Main advantages:

Heat transfer from warm walls is carried out 85% due to radiant heat transfer. With such heat exchange, people and pets in the room feel comfortable, despite the fact that the temperature is 1.5-2.5 C lower than with convective heat exchange. The convective component of heat exchange predominates when heating with a radiator. That is, by maintaining a temperature of 18-20°C instead of 21-22°C, warm wall systems make it possible to significantly save fuel over the season (up to 11% for a heating heat generator (boiler).
Reduced convective currents to a minimum, with wall heating it allows you to reduce, and in most cases completely stop, the circulation of dust throughout the room. Such conditions improve the microclimate, especially for human breathing.
Heat loss is compensated premises, within 150-180 W/m2. These are significantly higher figures compared to heating with warm water floors (100=120 W/m2). Such processes are due to the fact that the temperature of the water supplied to the heating system can be increased to 70°C in order to obtain a temperature difference between the supply return line in a warm wall system, which can reach 15°C (in heated floors this figure is limited to 10°C) .
Compared to water warm floors , warm water wall systems can make do with circulation pumps with lower productivity, which is due to the increased temperature difference that occurs between the forward and return pipelines.
For wall heating installation step pipelines is not limited to anything. This occurs due to the presence of temperature differences that occur between adjacent sections of the wall surface. These differences do not in any way affect the sensations of the person in the room.
When using variable laying spacing pipelines in a system of warm water walls achieve heat distribution in the room that is close to ideal. To do this, pipes are laid in areas 1-1.2 m from the floor (step 10-15 cm); in an area of 1.2-1.8 m from the floor - a pitch of 20-25 cm, and higher than 1.8 m - the pipe pitch can reach 30-40 cm. This value depends on the calculated data on heat loss. The direction of movement of the coolant is almost always taken from the floors to the ceiling.
Attention! The warm water wall system belongs to radiant heat exchange systems, so it is not recommended to place it on areas of the walls that will be covered by furniture during operation.
Using a warm water wall system makes it possible to heat two adjoining rooms. To do this, the loops are laid along internal partitions, which are made of materials with relatively low heat transfer resistance (reinforced concrete, brick).

The features of the warm wall system, which are listed below, determine the areas of its application where this heating method will give the maximum consumer and economic effect.

Examples of optimal application conditions:

premises with a small amount furniture and equipment placed near the walls (office premises, classrooms, corridors, bedrooms);
premises without free floor space, where water heated floor systems cannot be placed (bathrooms, swimming pools, garages, workshops);
rooms with high floor humidity, where the use of warm water floors is ineffective due to high energy costs for moisture evaporation (bathrooms, sinks, laundries, swimming pools);
any premises that have insufficient power of one separate system;
water warm walls - in addition to water warm floor, to compensate for heat loss through windows (any room).

When installing warm water walls, you need to pay special attention to calculating the temperature conditions of the outer walls. When designing a system, questions may arise - where to place the insulating layer, and how thick it should be. When using insulating layers on the outside, the freezing point will be shifted into the thickness of the insulation, and therefore enclosing structures can be made from non-frost-resistant materials. The disadvantage of this solution is that in addition to the energy costs for heating the premises, a significant portion of the thermal energy will be spent on heating the enclosing structures.

The option of placing layers of insulation on the side of the premises will lead to a shift in the freezing point of the walls towards the inner edge. This solution will require the use of frost-resistant wall materials, and rapid, low-inertia regulation of the average temperature of the coolant. Otherwise, situations are possible with complete freezing of the walls and the inevitable appearance of condensation.

The same requirements apply to wall heating, without the use of insulation. In such cases, erroneous calculations or delays in regulating heat flow can lead to significant heat loss through the external walls. Structurally, installing a warm wall system for specialists who are familiar with the construction of water heated floors does not present any serious difficulties.

When using wall heating using pipes for warm water walls, remember a few technological rules with which you can avoid the most common mistakes:

When creating a plaster layer, it is optimal to produce it in two stages. The first layer is applied over the reinforcing wire frames to which the pipes are attached. When this layer reaches the required strength, it is attached to plaster mesh and apply the final plaster layer.
On top of the finishing plaster layer you need to apply a layer of Strobi mesh or similar elastic paper. This measure is necessary to prevent the appearance of cracks in the leveling layer;
The thickness of the layers of cement-lime mortar above the pipe for a warm water wall should be within 20-30 mm.
Before starting work when installing warm water walls, it is necessary to install distribution and installation boxes in advance, for low-current and electrical wiring. The wiring itself is laid after final plastering in the thickness of the upper layers of plaster.
The supply of coolants to the pipes is allowed after the plaster layer has completely dried.
To avoid subsequent mechanical damage to wall heating pipes, it is recommended to carry out its executive diagram with reference to the pipe axes.

Water-heated walls can be used simultaneously with water-heated floors. Water heated floor is an independent pipeline system installed below the floor covering. These are closed systems through which water circulates. Both the existing heat source in the house and communal heating systems can serve as recharge for a water heated floor. And if the house has a boiler, then water-heated floors will completely replace the existing heating system. Such thermal systems will not leak, since they consist of flexible pipes durable material with a layer of screed that protects against any kind of damage. There are light and concrete system, depending on where water heated floors are installed. If the systems are oriented towards wooden country houses, then the technology for installing heated floors on the second floor and above will be used not in a heavy concrete screed, but in polystyrene foam, after which the floor is covered with a moisture-resistant gypsum fiber sheet. When installing this type of floor in city apartments, it is quite possible to use a lightweight polystyrene system. If these are large-scale construction projects, you can resort to a concrete screed.

If there are water heated floor systems in the apartment, heating radiators simply lose their value. To increase the heat transfer of a water heated floor, there is no need to use cork and parquet, since such floor coverings do not allow heat to pass through and quickly deteriorate due to incompatibility with coolants. To cover such floors, it is better to choose other materials, such as linoleum, laminate, carpet, tiles or porcelain stoneware.

You can buy pipes for warm walls in Kharkov from a warehouse. We provide delivery throughout Ukraine!

The desire to improve and modernize already quite effective things sometimes leads not only to the appearance of another razor blade or even smaller micro-bristles on a toothbrush, but also to real cost savings and the achievement of higher thermal comfort. Thus, the technology of creating a warm wall today is increasingly of interest to those who are trying to thoroughly study the features of each heating system.

Today, in addition to traditional radiator systems, floor, ceiling, and wall heating systems have been developed. All of them have taken root in the market in different ways. It must be said that the popularity of one or another heating principle largely depends on the awareness, first of all, of heating engineers. It's no secret that very often installation work heating system people whose qualifications leave much to be desired. Many of them have a passable command of only one technology, and are not at all interested in its alternatives. However, when they receive some kind of “exotic” order from a client, they boldly take on its implementation, not wanting to lose their earnings. But before that, they will still try to dissuade the client from an unconventional idea in favor of their “native” technology.

All this was said to the point that we all often become hostages of non-professionals, but no one forbids us to become more literate and make our homes comfortable, economical and environmentally friendly.

Why is wall heating good?

First of all, high thermal comfort. In “warm wall” systems, heat is distributed throughout the room most evenly and exclusively through thermal radiation. A warm wall acts as a source of this radiation, and since a person is an upright creature, he can most absorb the heat coming from the side. An example with a snow-covered slope in bright sunny weather shows the work of a warm wall very clearly. Despite the fact that the air temperature is well below zero, we are warm because we are in an area of intense scattered radiation emanating not only from the sun itself, but also from white reflective surfaces. As soon as we step into the shade, the thermal effect instantly stops and thermal comfort disappears in the area.

If a warm wall is used in the room, then thermal comfort is achieved already at 17-18°C. This is several degrees lower than with traditional radiator heating, which cannot but affect savings. By the way, with wall heating, there are no radiators in the room, which has a better effect on aesthetics. So, the “warm wall” system means high thermal comfort, cost savings and the absence of protruding heating elements.

Types of wall heating

Warm wall systems differ in the way these very walls are heated. The first type is the most ancient - air wall heating. Today, air heating looks a little different than in ancient Rome, but its essence remains the same. The heating element is located at the bottom, and between the finishing layer and the load-bearing part of the wall there is an air gap, the air in which, when heated, transfers heat to the wall.

Experts call this heating system hypocaustic. Ideally, the walls of a house should be constructed of hollow blocks, which, when laid in a certain way, would form interconnecting air channels inside the wall. A niche is provided directly above the floor in which the heating element will be located (usually a laid copper pipe connected to a water heating circuit).

Air wall heating, in principle, can be created with any design of its supporting part and in the absence of a niche near the floor. To do this, they make a plasterboard false wall, behind which there is air space, heated in the same way. In both cases, the wall heats up and radiates heat into the room.

A warm air-heated wall can be open. In this case, warm air, rising through the air ducts, enters the room through openings in the ceiling. IN closed systems air circulates inside the wall by convection.

Water surface type wall heating in principle it is very similar to a heated floor system. Copper, plastic or metal-plastic pipes through which coolant is supplied. The pipes are securely fixed with special fasteners. The direction of installation (horizontal or vertical) by and large does not matter, since the function of the pipes is to directly heat the wall. The pipes themselves are covered with a layer of plaster (in no case warm) or other finishing with good heat transfer properties.

Warm wall with electric heating It is arranged in a way similar to the previous one, with the only difference that in place of the water tubes there are special electric heating elements. Electric heating films can also be used, which are quite convenient to install. However, experts recommend using films only from European manufacturers, since they have a longer service life. Weakness Asian films in the oxidation of contacts, which must be made of high-conductivity alloys made using special technology.

Quite rare is the method of heating a wall using heat pipes, inside of which there is an easily evaporating liquid. A system of such pipes is laid in the wall, and a collector with coolant passes below. The easily evaporating liquid boils and rises in a vaporous state through the tubes, giving off heat to the wall. I must say that this method heat transfer is one of the most efficient in terms of energy savings. The fact is that as a result of using heat pipes, the volume of coolant in the system is reduced by 5-8 times. This system is less inertial, i.e. more controllable and heats up faster in the event of a “cold start”.

Where can a warm wall be installed?

Although a warm wall is an alternative to traditional radiators, it is still better to use it in conjunction with a heated floor system. To achieve high thermal comfort, the proportions of wall and floor heating must be adjusted. It is advisable to give priority to a warm wall in the living room, dining room and children's room. In the bathroom and kitchen you will need more underfloor heating, since these rooms are small and do not require a lot of energy to heat them. And finally, installing a warm wall on glazed verandas and in winter gardens, where the floor area is much larger than the wall area.

The “warm wall” system with a surface water or electric heater has several inconveniences, although not very significant. Firstly, it is advisable not to cover a warm wall with furniture, you cannot hang carpets on it, and in general it is necessary to block it as little as possible various materials, having low thermal conductivity. Secondly, trying to hammer a painting nail into it may result in damage to the heating tube or electric heating element. To accurately determine the areas where thermal channels pass, a special map of the wall is drawn up, using the coordinates of which the free spaces are then found. Also, for this purpose, you can use special thermal films that change color depending on the surface temperature. With the help of such a film it is easy to find the thermal channel located in the wall.

IMPORTANT: before creating a warm wall, you need to think about the furnishings of the room. The greatest restrictions apply to built-in furniture: heating the contents of the cabinet is absolutely pointless!

Advantageous features of wall heating

The coolant temperature in a warm wall usually does not exceed 30-35°C, and this makes it compatible with solar collectors, heat pumps and other low temperature sources.

The elements of the warm wall system are made so that they can be easily installed even by yourself, but the design of the system must be carried out by a specialist. Its effectiveness will largely depend on this.

A huge advantage, thanks to which the same thermal comfort is achieved, is the absence of air drying and unfavorable air ionization, which occur with high-temperature heating methods.

Speaking of ionization, which for some reason receives so little attention when choosing a heating method. From the school physics course we know that positively and negatively charged particles are called cations and anions, respectively. So, it turns out that cations, being in the air, increase the movement of dust, viruses and various allergens present in every apartment. Positive ionization of air is promoted by beam monitors and picture tubes, as well as hot metal surfaces, such as heating radiators. Numerous studies have established that the atmosphere in rooms where there is a high concentration of cations cannot be called healthy.

Anions - negatively charged particles, on the contrary, improve human well-being. At the level of sensations, this manifests itself as freshness, ease of breathing, and vigor. In order to increase the amount of anions in the air, it is necessary to use special ionizers, but it is also possible to achieve the desired ratio of cations and anions by reducing positive ionization, i.e., eliminating the cause of the formation of cations.

Warm wall systems eliminate air contact with hot metal surfaces, and therefore, in a room with such heating, balance is maintained between positively and negatively charged particles.

An old idea in a new embodiment

Combination idea heating device the surface of the wall is not new: it was first implemented in the late 60s of the last century, at the very height of panel construction. For this purpose, cavities were provided inside the reinforced concrete panels for coolant circulation, and the heating distribution diagram was formed during the installation of the panels and the construction of the house.

The success of wall heating systems is the result of precise engineering calculations and impeccable construction quality. Coolant passing inside concrete wall, heated its surface to 50-60 C.

The heat spread over the entire area of the wall and was transferred into the room by radiation. In this case, the convective component of heat transfer is completely eliminated

It should be noted that in houses built to last (and there were quite a few of them in the USSR), wall heating systems operate up to today, delighting the residents high level comfort.

Unfortunately, wall heating has not become widespread. Probably, the complexity of installation and high requirements for the quality of concrete panels with built-in reservoirs for the movement of coolant had an impact.

The idea of wall heating in the new, modern form, returned with the appearance polypropylene pipes, the unique properties of which allow them to be used not only for warm floors, but also for warm walls.

How are warm walls constructed?

To ensure comfortable conditions in the room, it is enough to make only the outer wall facing the street warm, compensating for heat loss into the surrounding space. If you decide to heat 2 or more walls, then for each of them you need to make a separate heating circuit, connecting it in the same way as a heating device.

The polypropylene pipe is laid on the wall surface in loops, the long side of which can be located vertically or horizontally. Both installation options are possible, but if the loops are horizontal and the coolant supply is connected at the top, the water will move downwards under the influence of gravity or by gravity.

When the loops are arranged vertically without circulation pump indispensable: the coolant has little chance of overcoming the forces of internal friction in the system, especially if the pipe length is several tens of meters.

Laying polypropylene pipes on the wall surface is carried out without the use of additional thermal insulation materials. There is no need to lay a layer of foil or vapor barrier under the pipes.

In this case, it is desirable that the walls have minimal heat losses, and their thermal insulation is made from the outside of the building. Otherwise, the location of the dew point may be shifted inside the building, which will inevitably lead to the formation of dampness on the walls, and thermal energy will be spent on drying the walls and not on heating the room. Outside, the surface of the walls can be plastered or covered with panels.

The laying step of polypropylene pipes can be different: there are no restrictions on this. Typically, pipes are laid at smaller intervals at the bottom of the wall, and at larger intervals at the top of the wall.

Advantages of warm walls

The use of warm walls for heating a house can significantly increase the area of the heating device compared to conventional heating radiators. And since the heating area increases, then in order to obtain an equal amount of heat, it is possible to reduce the temperature of the coolant, for example, to 50-60 C, and this is a low-temperature heating system that is more comfortable for humans.

In addition, with the help of warm walls it is possible to reduce the share of convective heat transfer, replacing it with more comfortable thermal radiation.