- 1 Mixing unit for floor heating with his own hands
- 1.1 General concepts of mixing unit "warm floor"
- 1.2 Schemes pump-mixing units and principles of their actions
- 1.3 Mounting the mixing unit with their own hands
Mixing unit for floor heating with his own hands
Underfloor heating systems, in which very few people have heard a dozen years ago, have become part of the everyday life of modern houses and flats, especially for those owners who are thinking of creating maximum comfort of living in their domains. In advertising newspapers - the mass of advertisements about the services on the installation floor warming systems, but such is the "device" of many of our men, they just "itching" to do everything on their own.
Mixing unit for floor heating with his own hands
From a variety of types of "warm floor" it kind of water is among the most complex and expensive to install, however, it is believed that it is much more economical in terms of the subsequent operating costs. Work on the installation is complex in itself, if it is considered already, if only in terms of laying the pipe loops, hidden in the floor thickness. But it will be very naive to believe that this major worries are left behind, and it is only necessary to cut into the supply pipe and the "return flow". No, we still have to create almost a kind of "control system" zero system, so that the floor heating earned and bringing into the house only comfort, but not a lot of trouble. The main element of the system is pumping and mixing unit, which is directly responsible for maintaining the desired temperature in the circuits and providing circulation of coolant thereon.
Such devices can be purchased off the shelf. And is it possible to collect a mixing unit for floor heating with his own hands? Yes, it is quite feasible task - and the subject of this publication.
General concepts of mixing unit "warm floor"
What is the importance of pumping and mixing unit in water "warm floor" system?
That any work was successful, the executor must understand what he is doing, and what the principle of the products produced by them. Is no exception and our case: to begin to be fully present, what are the functions assigned to the pumping and mixing unit - it will be easier to understand in the future in its design.
Temperature settings in the "classical" and the heating system in the "warm floor" system &# 8212; very different
So, to begin with, that the temperature of the circulating coolant circuits floor heating significantly, almost half, is different from those of the conventional heating system, where the role of the heat exchangers operate radiators or convectors.
Thus, in the conventional high-temperature heating systems, water supply pipes are usually balances at 70 ÷ 80 ° C, and in some cases may even exceed those limits. It was under these operating modes were created earlier and is now primarily generated heat line, produced the vast majority of models of boiler equipment.
But those temperature regimes that are the norm for classical heating systems, it is not acceptable in operating conditions "warm floor". This is explained by the following circumstances:
- If we take into account the active heat transfer area (almost the entire surface of the floor in the room), and we add here also a rather impressive heat capacity of covering, which encloses the tube "warm floor", it is obvious that in order to achieve in the room camphor temperature large heating is not required .
- The threshold of perception of comfort floor surface heating bare foot is also limited - typically this is sufficient for the temperature to 30 ° C. Agree, it is not very nice if the bottom starts to "bake".
The balance of the normal human body temperature, and heating causes the floor surface limited to a maximum threshold of 30 degrees, or the feeling of comfort just lost.
- The vast majority of finishing flooring used in living rooms, it is not intended to strong heating. The temperature rise above the optimum leads to a deformation, to the appearance of gaps between the individual parts, to failure of the tool joint, the formation of waves or "humps" and other negative consequences.
Overheating of the floor surface can cause significant deformation of the coating and even to state its complete unfitness
- The high heating temperature can be destructively influence the state of the concrete screed in which "rest" pipe loops "warm floor".
- Finally, elevated temperatures quite helpful and pipes laid contours. It is correct to understand that they are rigidly fixed in the screed, unable to free thermal expansion, and high temperatures in the walls of the pipes will arise very strong internal stresses. And this is - a direct path to rapid deterioration, to increase the probability of occurrence of leaks.
Recently went on sale a model of boilers, which may well work in a "warm floor" mode, that is to give low-temperature heating. But does it make sense to buy new equipment, if you have the opportunity to manage the available? In addition, the "warm floor" in the "pure" are used not so often - usually on a scale of one house combined with the "classics". Putting two separate boiler? &# 8212; very wasteful. Better a few to improve your system, selecting from her land "warm floor" and on the border of this division is just install the same pump-mixing unit, which will be carried out it.
There is another factor that explains the need for pumping and mixing unit. It is one thing - to circulate in the main heating circuit, and the other - in padded floor heating circuits, each of which reaches a length of tens of meters, with many twists and turns, giving a significant increase in flow resistance. Hence, the need for pumps, which is also usually included in the node circuitry, which, incidentally, is reflected in its name.
The principle of operation of the mixing unit
The task is clear - it is necessary, without violating the basic mode of operation of the heating system, to ensure that in the contours of a "warm floor" circulate coolant at a much lower level of heating. How to achieve this?
The answer is obvious - quality control, ie to mix with the hot flow cooler. A complete analogy with what we are doing more than once each day, adjusting the water temperature in the shower or in the kitchen blender.
The principle of qualitative adjustment of the water temperature is very clearly demonstrates a conventional kitchen mixer
With hot flow - all clear, but where to get chilled? Yes extending from adjacent tubes "the return" at which the heat medium gives heat to the heating devices or "floor heating" circuit is returned back to the boiler room. By varying the proportions of hot and mix with the cooled liquid, can achieve the desired temperature.
Of course, on the complexity of the mixing device assembly it is very different from ordinary household tap. And challenges it faces more responsible!
Thus, the mixing unit must be able to work without constant human intervention - to automatically monitor the temperature levels and to make operational changes in the flows of the mixing process, changing them quantitatively. Often there is a situation where additional heat input, and does not need, and equipment must simply "lock" loop, providing only internal circulation of coolant through it, to the desired cooling.
One gets the impression that all this is very surprising to the layman. Indeed, if you look at pumping and mixing units of factory production, offered for sale, is, at first glance, to understand the maze of pipes, taps, valves, etc. - very difficult. And the cost of such assemblies looks very frightening.
Not having a basic understanding of the mixing units to understand their device - not so easy
But it turns out in practice realized only a few running schemes, and if you understand how they work, tol similar pumping and mixing unit it is possible to collect and own resources. Analysis of these schemes, we will devote the next chapter of our publication.
You need to make a clear right - this article is devoted to pumping and mixing sites, but connected to supply him and "return flow" sewers referred, of course, will be, but their device will not deepen. Just for the reason that the system unit &# 171; underfloor heating&# 187 ;, namely - its structure, operation principle, the order of assembly and balancing, still require detailed consideration in a separate publication.
Schemes pump-mixing units and principles of their actions
five were selected from the entire diversity schemes such mixing sets. The main criteria for selection were the ease of perception of the principle of work and availability to independent manufacturing. That is, the proposed design is quite possible to assemble from parts available in the free market, and it does not require special training - just steady skills in conducting a conventional plumbing installation.
Schemes certainly differ, but for simplicity of their perception, they are made in one graphic principles, preserving images and enumerations of the same elements. New items that will appear in the schemes, will be assigned drive letters from the increase.
In all schemes adopted one orientation - the supply pipe supply and to the left "of the return," and access to "comb" - Collector of floor heating - the right. Color-coded tubes clearly indicates their destination. Himself a collector in reality can be directly adjacent to the pumping and mixing unit (it happens often), or even be located at some distance from it - it depends on the features of the room and space for equipment. On schemes of work principle is not reflected at all.
The pipes can be any, as desired wizard - AIV from ordinary steel to plastic (polypropylene or metal-base) or corrugated stainless steel. Accordingly will vary and some accessories. Thus, for example, brass are shown in Schemes tees or bends, but they may be executed and from other materials.
Suitable thickened with variable hues arrows indicate the direction of coolant flow.
This circuit uses a conventional thermostatic valve, for heating radiators. The circulation pump is arranged in series.
The scheme is considered to be one of the easiest to install, but it is quite effective.
One of the simplest schemes of pumping and mixing unit with a serial arrangement of the circulation pump
Let's go through the detail parts and devices, circuit components:
- "a" - pipes shown color-coded for ease of reference. As already mentioned, can be used various types of pipes, as long as they conform to the characteristics of the operating conditions of the heating system.
&# 8212; "A.1" - input supply pipe from the general contour of the heating system;
&# 8212; "A2" - exit to tube "return line";
&# 8212; "A3" - Submission to the collector of "warm floor";
&# 8212; "A4" - the return of coolant to the reservoir.
- "B" - Valves - Ball Valves. It is important - they have no role in the process of adjustment of temperature or pressure in the "warm floor" system. Their functionality is limited, but at the same time - no less important. The presence valves allows disconnection of individual heating units when it is due to the need, for example, carrying out any maintenance work.
The normal position of the ball valve - only "open" or "closed". In the process of system adjustment it takes no part
Special design requirements stopcocks for the mixing unit is not shown, except, perhaps, the quality of their performance. But it is desirable to use cranes, fitted with a cap gaykoy- "American" (as shown) that allows you to quickly carry out the dismantling site, without the need for complex operations. Accordingly, the inlet ( "B.1" and "B2"), These coupling nuts must be from the side of the mixing unit.
cranes "B3" and "B4" (Between the mixing unit and the collector) can not be considered essential elements of the system, but it is better not to spare money and for them. Their presence makes it possible to disconnect manifold and completely dismantle the assembly without knocking calibrated balancing circuits.
- "at" &# 8212; mechanical cleaning filter coolant (often also called "skew filter").
"Oblique filter" in the section - will prevent valve system of pump-mixing assembly and the collector from contamination or premature wear
This element can not set, but only if there is complete confidence in the cleanliness of the circulating coolant. Typically, filtering devices are provided on the boiler level. However, to completely eliminate the possibility of getting suspended solids to fine adjust "warm floor", and you can insure.
There is such a filter is inexpensive, but it will guarantee that the valve device of the mixing unit and the tuning mechanisms contours will not get any solid particles that could disrupt their work correctly. In addition, it should be remembered that the suspended solids in the coolant accelerate wear of the seals valves.
- "D" - devices for visual monitoring of coolant temperature (thermometer).
Various types of thermometers used in heating systems
type thermometer can be any - how convenient wizard. For example, devices used with probes which are in direct contact with the coolant. If is easier - you can buy a consignment model, but will be stopped already conducted at a temperature of the pipe wall. The thermometer can be liquid, mechanical with dial indicator or digital - it is convenient when using the electronic heating control systems.
The diagram shows an embodiment using three thermometers:
&# 8212; "D.1" - measures the temperature in the common supply pipe heating system;
&# 8212; "D.2" - to control the temperature of the coolant outputted from the mixing unit to the collector;
&# 8212; "D.3" - allows to monitor the temperature difference at the inlet and outlet manifold. Optimally, this difference should not exceed 7 ÷ 10 degrees.
Such an arrangement of devices seems optimal as it gives the most complete picture of the system to work correctly. However, many masters for reasons of economy and cost less thermometers.
- "D" - main control element of the mixing unit of the structure - a thermostatic valve. This is exactly the same valve that is usually mounted on the radiator.
In this scheme applied thermostatic valve for heating radiators. Better to buy a model, designed for single-pipe system
A small subtlety. Available valves are presented with the radiator designed for single-pipe and two-pipe heating system. In our case the mixing unit is preferably a model for one-pipe system, as a more productive. It is easily distinguished by a number of features such a valve has a slightly larger diameter of the "barrel", is present in the marking character "G », and a protective cap - gray.
coolant current direction is indicated by arrow on the valve housing.
- "E" - thermostatic head, which is put on the thermo-valve (with the union nut M30 or a special type of lock). It is important - in this case the required head with remote sensor only ("Well") Connected with it the capillary tube.
Thermostat with remote temperature sensor
Apparatus head such that when the temperature changes and its effects on the mechanical thermo-valve stem - with increasing valve is closed is lowered - conversely, opens the coolant passage.
How are and how to operate thermostats for radiators?
This publication describe all these devices will not. This is because of the considerations that apparatus and principle of operation of thermostats for heating radiators We discussed in detail in a separate article of our portal.
The temperature sensor is applied to the tube - for this there are special spring clamps. But the question immediately arises - and exactly where it should be?
There are two options, each of which is good in its own way.
&# 8212; First option: The sensor is to the pipe feeding from the mixing unit into the manifold "warm floor". The advantages of such an approach - in coolant circuits supplied at a stable temperature, ie, completely exclude the possibility of overheating. Disadvantages - mixing system does not react to changes in ambient temperature (unless, of course, the corresponding additional devices are not placed on the reservoir). For example, in cold weather or indoor temperature rise, the mixing unit will still be supplied to the coolant heating with invariable level.
&# 8212; The second option: The sensor is in the return pipe from the reservoir to the mixing unit (to bridge in "D.3" area thermometer). Advantages - temperature stability is in this area, that is, taking into account already given in a warm room. But heating the coolant level in the supply pipe to the collector will vary according to the change of external conditions. Colder in the room - the contours gave more heat - thermostatic parted more, and consequently, on the contrary. Disadvantages - the existence of the likelihood of overheating in the contours of "warm floor". For example, after filling it with the first pump to the collector at first will be fed too hot water until it warms screed. Another option - too cold snap in the room (for example, emergency ventilation of wide open windows) may also provide flow to the circuits are too hot for them fluid.
However, can be avoided by deliberate exploitation of all this negativity. And even better - to provide sites for placing the sensor on both pipes in places mentioned above. Rearrange such a sensor - minute task that does not require any tools.
- "Z" - plumbing tee by which the bridge is formed between the flow and return pipes - bypass ("and"). Through this bypass and will be the selection of chilled coolant to mix it. And the mixing process, in fact, takes place in a tee "Z.1".
- "to" - balancing device. The bypass valve is recommended to set (may be even an ordinary plumbing) with which is performed the exact configuration of the system after it is started, in particular, the necessary pressure and productivity indices of the circulation pump. The presence of such adjustment allows you to "strangle" the flow to the manifold and the mixing unit no zones with excessively high blood pressure, or vice versa, negative pressure. The pump will operate in the most optimal conditions, decrease noise system.
Block valve will work exactly otbalansirovat pumping and mixing unit
The optimal solution - installation is not sanitary valve, and the so-called block-crane, such as the one often put on the "return pipe" radiator. In terms of functionality, in principle, there is no difference, but in terms of ensuring the safety of the settings - it is obvious. Balancing is carried out with a special key, and then adjusting device is closed dongle. That is, until it does not reach, for example, the playful children's hands.
Temperatures in flow and return manifold floor heatingThe temperature in the feed manifold, ° CThe temperature in the return manifold, ° C
Explanations for performing calculations
- The coolant so called knowingly - the more it is pumped per unit of time, the more heat is moved from the source (boiler) to a consumption place (to the contours of floor heating). Hence, one of the initial values for calculating the minimum required capacity is the area of the premises in which organized such type of heating circuits and which are connected to the mixing node under consideration.
Here, too, can be the difference - it is one thing when a "warm floor" is the only source of heat, and quite another - when he organized only in order to maintain a comfortable atmosphere in the room: the amount of thermal energy will be different. In these input fields you must specify the values of the area, with the possibility of differentiation of the specified grounds. In this case, if the "warm floor" is made for the kitchen, bathroom, hallway or bathroom, it is better to indicate that it is the main source of heat.
- To estimate the amount of transferred heat energy necessary to know the heat capacity of the coolant (which is already incorporated in the calculation of the program) and the temperature difference in the supply and return manifolds. This difference is typically less than 10 degrees, despite the fact that for a comfortable perception, as already mentioned, sufficiently heating a level not more than 30 degrees. However, in the calculator, there are two slider, which you must specify the intended operating temperature of the system.
- Sometimes, instead of water (the characteristics of which are already incorporated in the program) in the heating systems applicable nonfreezing coolant. To the results of calculations for him were more accurate, you can specify the density and heat capacity.
The final result will be displayed in cubic meters per hour, liters per minute and per second - as someone easier to read.
What is the minimum pressure should create a circulation pump mixing unit?
The total heating system is definitely worth your pump, but hope for the pressure created by them is not necessary. As seen from these diagrams and the principles of their operation, shaped valve closes completely, and all the pressure required for circulation of the coolant along the contours of underfloor heating, will only provide a pump built into the mixing unit.
Located below the calculator will determine the minimum value of the desired pressure. And in the application - some explanations on how to use it.
Calculator determining the minimum required pressure circulation pump
Enter the requested data and press "Calculate the required minimum pressure pump"The length of the longest path that is connected to the collector, m Inner diameter of the pipe into the heating surface - 16 mm - 20 mm - 25 mm
Explanations for the calculations
- the collector is connected to the mixing node, which is already powered circuits "warm floor". According to the laws of hydraulics, the pressure created by the pump, the collector will be equal for all the connected circuits, and to fine-tune usually on each of them set their balancing device. However, these valves allow only "strangle" the excess pressure, for example, in the contours of the minimum length. A calculation, obviously, should be conducted on the longest circuit, as it is in it will be given the maximum hydraulic resistance. Therefore, in the data input field must specify the length of the longest contour considering pipe liner thereto.
- Hydraulic resistance is higher, the smaller the diameter of orifice tube loop "warm floor". Therefore, this parameter is specified in the next field.
Also the pipes themselves, have considerable resistance and other system elements - fittings or valves. But an amendment to this fact is already taken into account in the calculation algorithm.
- The resulting value will be shown in several units: Pascals, and decimetres meters of water column. It is made of those considerations that the various units can be used in passports pumps from different manufacturers.
For example - a diagram of the hydraulic characteristics «Sprut LRS 15-6S-130" circulator
When selecting a pump should look through its data sheet - there is usually applied a diagram performance tradeoffs and the pressure generated in different operation modes (most modern devices has such mode switch).
Mounting the mixing unit with their own hands
It is correct to understand that a single assembly mixing unit technology is not, and can not be. Anyone who understands the techniques of plumbing installation, understands what is at stake, and it is enough concept to find the right accessories and make self-assembling them. The more so because there is no unity of approaches to this matter. So, one masters prefer to engage with the metal, using threaded connections. Others - are "apologists" plastic, and vsoe try to perform it with its use. In the third there is a welding machine for polypropylene, and they believe that the cheapest way to collect node predominantly of the details. So evaluate their abilities and financial capacities, and choose your own mount technology.
If there is no experience, then consider mixing assembly "ground" node for producing skills - we should not. It is better to start to practice on simpler compounds.
In the following example, the master applies the metal components and which is typical - widely used coupling parts CAP gaykami- "American women", i.e. practically without costs "zapakovki" connections - sufficient application pads. Certainly, it is very convenient approach, though not particularly cheap. But along with the reliability of connections, it is possible to dismantle any element of the created node, for example, to replace it.
If, however, a simpler but cheaper - the same can be done with conventional threaded connections, "zapakovyvaya" on hemp with sealing paste on fum-tape or other modern seal - the good, the lack of such materials is not in our time.
|On the desktop, start to spread the required components for the assembly site, the necessary tools for installation. |
The example shown in the scheme corresponds fully №2, discussed above, except that instead of the three-way valve with a removable thermal head applied similar, with mix flows but with integrated temperature sensor.
Model - «ESBE VTA572», specially designed to work in the system "warm floor".
|This, by the way, be sure to look for when selecting a product. |
In this case, the packaging clearly shows that the three-way valve -. It is for the "warm floor"
As can be seen by the presence of other icons, there may be other options.
|Here the crane itself, so to speak, live. |
Very clearly visible colored arrows showing the direction of the hot and the cooled coolant flows.
From above in a plastic housing is placed sensor, there is a scale controller for issuing precise temperature values.
Graduation from this device - to the degree in the range of 20 to 43 degrees, that is specifically for systems "warm floor".
|Ready to install the next most important element of the system - the circulation pump. |
In this case, the model is used one of the most reputable brands "Wilo ».
|It is possible that the pump will be necessary to spend certain preparatory operations. The fact that there are certain rules for its installation, and to ignore them - is not allowed. |
Not only that, the flow direction must correspond to the arrangement of the mixing unit. Such pumps are so-called wet-rotor must be positioned so that the axis of rotation of the rotor taken exclusively horizontal. And one more condition - switching and control unit must not be lower than the pump.
So, you must first conduct a "fitting". If at least some of the conditions is not met, we will have to make in the layout of the pump some amendments, namely - to deploy position of the drive unit relative to the working chamber at 180 degrees.
It's easy. The drive is attached to the bottom of a "scroll" through the screw - in this case a hexagon. Special key, these screws can be turned out.
On most models of pumps, screws - four.
|Since the pump is brand new, the connection has not yet been acidified, unscrewing the screws should not cause difficulties.|
|Screws are removed, and it is possible without completely severing the "halves" of the pump, just gently rotate the upper part relative to the lower half-turn. After this will accurately align the screw holes and produce reverse the tightness of fasteners tightly to ensure reliable sealing of the device. |
With the pump until finished - it can be temporarily removed so that it does not interfere with the beginning of installation.
|Exactly as in the scheme shown above №2, in the present node will be three thermometers: supply pipe before the mixer, to outlet pipe manifold (downstream of the pump), and the return pipe from the reservoir (to bypass). |
Apply arrow thermometers with probes which are required for installation tees (devices are screwed in their central branch pipe).
To get correct readings of all three thermometers, it is desirable to reconcile them with the reference, evidence which is not in doubt (it can be any, eg alcohol or mercury in the instrument - the main thing that it was accurate).
It is enough to put all the thermometers on the table, and give them time to "stabilize", about 10 minutes.
|You can then verify the evidence. If you marked certain deviations from the reference instrument, it is possible to make an adjustment. |
At the end of the probe (if to remove from it the protective cap) has a generally thin under calibration screw screwdriver. Turning slightly, put the arrow on the exact temperature.
After that, put in place protective caps, and thermometers can also be considered ready for installation.
|You can navigate to the site assembly. |
In this case, the master started from the area of the entrance to the feed of a thermostatic valve, i.e., in fact, along the coolant flow.
The first shut-off ball valve is equipped with "American".
By fitting "American" joins tee at the thermometer.
|Opposite outlet tee pipe is twisted with a mixing valve. |
Important: do not forget the flow direction arrow - there must be the entrance of hot water.
|Here are some entry node until it turned out after the assembly.|
|The central housing tee mounted thermometer. |
In this example, the master preferred to orient and thermometers, and "sheep" ball valves towards the front, but in each case this position is chosen for reasons of convenience and control of visual instrument readings. Their functionality and accuracy of the position relative to the axis of the pipe - no effect.
|Set bridge-bypass. |
To this end, the lower entrance of the thermostatic valve is screwed to the tube running with him in complete union gaykoy- "American."
Such a measure would easily detach the top half from the bottom of the mixing unit, if required its demolition, for example, to remove broken or requiring thermo-prevention.
|Bottom to the fitting with union nut screwed onto the tee. |
It outputs a predetermined flow direction: right - from the return manifold "warm floor" on the left - in the direction of the overall "return flow" heating system.
So you can proceed to the assembly of these parts.
|The left portion of generally simple - it is, in fact, includes only the shut-off ball valve, which is connected to the tee through the union with "American". |
The check valve decided not to - it need still is not obvious, and the probability of emergency situation because of its absence - is negligible.
But if he is needed, then put it between the tee and the crane - too small difficulty.
|On the opposite from the tee area is not enough without a thermometer that is fitted tee for its installation.|
|Here's the plot - already installed thermometer.|
|We proceed to the assembly of the upper right-hand "branches" of the valve through the pump in the supply manifold. |
Its distal portion constitute shutoff ball valve, the straight tube portion (it is necessary to calm the mixed stream), for setting the tee bulb and one of the couplings with the "American", included in a circulation pump unit.
|The section from the pump to the outlet assembly.|
|By the way, do not forget to install shut-off valve is also at the bottom of "branch", coming from the return manifold to bypass.|
|The second socket with a cap nut of the pump set "is packed» into the right valve port through which the mixed stream will exit coolant.|
|Node is almost ready - there were only put in place the circulation pump.|
|It's hard to do. |
The union nut fits full-time pad. Then the nut is screwed onto the input pump tube, but not yet crimped.
Before installation, no harm will once again make sure that the direction of the flow created by the pump, and as shown by the arrow on its case, corresponds to the scheme - from the thermostatic valve in the direction of feed manifold "warm floor".
|On the input side, that is, from temoklapana pump nazhivlen.|
|Exactly the same operation is carried out and the outlet of the pump: installing gaskets and baiting gayki- "American".|
|In fact - the main assembly is now complete.|
|The pump is attached to the correct position (as mentioned above) and the union nuts are tightened. |
, A final close-fitting all plug connections.
After that, you can proceed to install the assembled unit in the intended place for him and his connection to the pipes of the heating circuit and to the collectors of floor heating.
|In order to save space, and sometimes for reasons of economy, often refuse to install thermometers. |
This illustration shows the same assembly, but with the covers tees and thermometers.
It has become cheaper and more compact, but that does not mean better.
Lack of control over temperature will seriously complicate not only to debug the system, but its safe operation. In this saving is - our own peril.
Well and if the place does not allow, try at least a surface-type thermometers - for them very little free sites exactly there.
And at the end of the publication - is another clear example of self-assembly of simple mixing unit for the "warm floor" system. It is noteworthy that the master installation combines two technologies - threaded joints and solder metal elements &# 8212; parts of polypropylene.
Video: Simple by mixing unit - with their own hands.