The use of structural elements such as mixing units in the "warm floor" systems, as well as ventilation equipment, allows you to adjust the temperature of the air or water entering the room. When installing them, certain rules must be followed.
Why do I need a mixing unit for a warm floor
This type of equipment is used to adjust the temperature of the coolant mainly in private homes. Underfloor heating is usually connected to the boiler. Therefore, the water in the pipes laid under the screed and the water intended for domestic use have the same temperature. And this, of course, is far from always convenient, especially in the summer. Hot water is also needed at this time, but the heated surface of the ceiling will obviously be superfluous. In addition, in the absence of a mixing unit, floors can be too hot even in winter.
What is a mixing unit
These components of the "warm floor" systems consist of the following elements:
- circulation pump
- control valve or valve,
- check valve
- ball valves
- balancing valve
- filter
- temperature sensor.
Principle of operation
Usually this element of the heating system "warm floor" is placed on the supply pipe. In the event that the water temperature exceeds the specified values, the valve will open and the coolant that has already cooled from the return will begin to flow into the main. As a result of mixing, the temperature of the water in the feed pipe will decrease.
For small houses, only one mixing unit is usually used. In cottages and two-three-story suburban buildings, several are installed. Depending on the principle of operation, these elements can be included in the system in parallel or in series.
Cost
Since the self-assembly of this element is a technically complicated procedure, experts advise the owners of suburban homes to buy a ready-made mixing unit. The price for it, depending on the brand, degree of equipment and performance, can fluctuate around 7-15 thousand rubles.
How to choose
First of all, when choosing this equipment, you should look at the brand of the manufacturer. Most likely, for example, the Smex mixing unit, which includes ARA 659 servomotors, is designed to work very well. The latter are designed to proportionally control the temperature of the coolant.
Valtec nodes are another popular brand. Their main advantage is the ability to manually adjust the floor heating.
This equipment is also selected depending on which boiler is used in the system, as well as on which, in fact, the floor heating scheme itself is developed. When buying, you need to look first of all at the permissible water temperature, maximum and working pressure, as well as the pressure head of the pump, which should be equal to six meters.
How to install
In private homes, mixing units with a two-way valve are usually used. Such equipment is installed in the following order:
- Clamps are fixed on the wall opposite the pipe.
- The unit is connected simultaneously to the pressure and return pipes (through tees with thermometers and a ball valve), as well as to the wall.
- Tees are connected bypass.
- A pressure circulation pump is connected to the bypass .
- The ball valve on the supply line is connected to a short tee pipe and flow meter.
- At the end of the latter, a dummy valve is installed.
- Bottom valve also with tee, closed valve.
- If necessary, automated drives are connected.
- Outlets of all heating circuits are connected to the tees.
- The mix knot is configured.
Of course, the installation of equipment will be faster if, before the installation begins, a floor heating scheme is drawn. The node can be located at any convenient point in the system. But it’s better to embed it where there is less chance of air bubbles entering the coolant. You also need to make sure that no parts of the unit that are energized are exposed to water.
Terms of Use
When using a node of the "warm floor" system, first of all, the manufacturer's recommendations set out in the instructions should be followed. The temperature and pressure of the water should not exceed the performance indicators, and in extreme cases - the maximum allowable.
The use of mixing units, even equipped with filters, increases the requirements for the quality of the coolant. Water should not contain solid impurities. It is highly undesirable for chemically aggressive substances to be present. The design of the assembly may include vulnerable parts made of copper, plastic, zinc or rubber.
Supply unit mixing unit
Structures of this type are used in systems equipped with water heat exchangers. Their main purpose is to maintain the temperature of the air entering the room at a level set by the owners.
Mixing units of this type work in exactly the same way as elements mounted in “warm floor” systems. The difference is that in this case, three-way valves are usually used . Assembly is carried out as follows:
- A filter is installed on the return pipe of the heat exchanger.
- Next, a circulation pump is connected.
- An electrically actuated valve is mounted.
- The valve is connected to the supply line bypass.
- On the return and supply pipe, ball valves are installed and connected by bypass. On the latter, a check valve and a control valve are mounted in series.
- An automatic air inlet crashes into the supply line.
- Both supply and return pipes are equipped with service taps.
As you can see, it is quite difficult to mount the mixing unit of the supply unit. And therefore it is better to entrust this work to specialists. If errors are made during the assembly process, the ventilation system may not work properly.
The ventilation mixing units are also operated according to the recommendations of the manufacturer of this particular model. It is important to monitor the quality of the coolant in this case.