The so-called warm floors have proven themselves as a system for heating private houses. It is not uncommon to find dwellings in which only a few rooms are heated in this way. But the tendency to heat the whole house with warm floors is gaining more and more popularity. You can also find combined heating options - underfloor heating and familiar radiators.
The heating system that feeds underfloor heating is usually around eighty degrees Celsius. For warm floors, such a temperature is unacceptable, as it can lead to damage to the flooring and interior items, and it will be uncomfortable for people to be in such a room. For such systems, the temperature is not higher than 40 degrees. Therefore, they provide for the V altec mixing unit. Below we will go over all the details about him.
Do I need to install such a node?
Let's see how the average heating system is made. So sheconsists of the following elements:
- Heating boiler.
- Coolant.
- High temperature circuit.
- The required number of circuits for underfloor heating.
As noted above, the boiler heats the coolant to 80-90 ° C, and the temperature of the floor itself should not exceed thirty degrees. Taking into account the height of the screed and the fact that the floor is provided with a floor covering, it turns out that the temperature of the coolant circulating through the pipes can be up to 55 degrees.
Accordingly, this can be achieved by connecting the underfloor heating circuit to the external circuit through a pump-mixing unit (including V altec). It is worth adding that they are allowed to be absent in the underfloor heating system when the installation does not heat the liquid too hot, and also if the heating system is built without the use of high temperature circuits.
How does the pump and mixing unit for underfloor heating work
Let's analyze the principle of operation of this element, designed for underfloor heating systems. Let us omit the process of heating the coolant with a boiler and proceed immediately to the stage of interest to us. The heated liquid is drawn to the collector of underfloor heating and, due to the presence of a special safety valve, stops in case of too high a temperature. Pressure is formed, leading to the fact that the damper opens, letting in the cooled liquid from the return circuit (meaning the cooled liquid that has passed through the entire circuit). The valve closes when the water temperature inthe collector becomes favorable to the system.
Let's take a closer look at the collector that provides the optimum temperature in the warm floors and maintains the required pressure for the circulation of the coolant. Its main parts:
- The safety valve mentioned above. It is designed to mix when the water in the collector is unacceptably hot.
- A circulation pump that maintains water pressure, creating conditions for even heating of the floor.
Also, the collector assembly may have other auxiliary components, such as a bypass (a device designed to protect against overloads), various valves and air vents.
It is absolutely certain that the mixing unit is installed before the underfloor heating circuit, however, specifically with the place of installation, not everything is so simple. It can be located both in the boiler room and directly in the heated room. Mixing units differ in the valves that they use. The most common are two-way and three-way.
Two-way valve
Such valves are called supply valves. The design of such an element includes a liquid sensor that checks the supplied coolant. If it becomes necessary, it stops the supply of hot media from the unit.
As a result, water is supplied from the return circuit for the mixture all the time. When this liquid cools down sufficiently, a portion of the hot coolant is added using a valve. Based on this information, it can be hypothesized thatthat a system with such valves will never overheat, and a warm floor will last a long time. The undoubted advantage is also smooth adjustment, since the valve has a small throughput.
Many professionals opt for two-way valves when installing a mixing unit. However, it is worth noting that for their use it is necessary to fulfill one condition - the area of \u200b\u200bthe heated room should not be more than 200 square meters. m.
Three-way valve
This type of element is different in that it is both a bypass valve and a bypass at the same time. Inside the three-way valves, the hot coolant and liquid from the return circuit are mixed. There is also a valve between the supply and return. Its position, respectively, regulates the supply of coolant.
This type of connection is universal, it is applicable for large systems (a mixing unit with a large number of circuits). However, it was not without drawbacks. There are times when the thermostat gives a signal to the valve to open completely, and, accordingly, water is supplied to the collector with a temperature of up to 90 degrees. As noted above, such a temperature, together with sharp jumps, can lead to breakage, namely, to the fact that the pipes will burst.
Another drawback is the high throughput. This fact can lead to a sudden change in temperature even with a slight displacement of the valve.
Outdoor temperature sensors
Such devices are needed insystem for automatic adjustment of the coolant depending on weather conditions. For example, when it gets colder outside, a signal is given to increase the temperature of the coolant, and in case of warming, the sensor tells the system that the floor temperature can be lowered.
The valve is designed to rotate 90 degrees. A special controller divides these 90 degrees into 20 sections and monitors the weather outside the window. If the temperature of the carrier does not correspond to the weather conditions, then the valve turns to the required number of divisions. Naturally, these manipulations can be done independently, but this is very inconvenient.
Mixing unit diagram
Let's consider the most popular mix node schemes. It should be said that there is a need for thermostats, flow sensors and valves for each of the manifolds.
V altek pumping and mixing unit is designed for one circuit. The average floor area is 20 sq. m.
Notation on the diagram
- Mixing valve.
- Nipple 1-three quarters.
- Circulation pump.
- 1-1/2" Nipple.
- Ball valve ½" (F/M).
- 16-1/2" connector.
- 3/4"-1/2" futorka.
- Half-inch keg.
- Half inch tee.
- Ball valve 1/2" (male/male).
V altek mixing unit with one circuit and automatic adjustment
Symbols:
1. Mixing valve.
2, 16. Futorka 1-1/2 in.
3, 8. ½ faucet.
4, 7, 11, 21. 16-1/2 connector (male).
5, 6, 12, 22. Metal-plastic pipe.
9. Nipple 1-1/2 in.
10. Tee ½ in.
13. Thermal head with remote sensor.
14. Nipple 1 in.
15. Union nuts pump 1 inch.
17. Elbow ½ inch.
18. Circulation pump.
19. Extension ½ 100mm.
20. Thermal head sensor.
V altek mixing unit with automatic adjustment, providing from two to four contours of underfloor heating. Heating area - from twenty to sixty square meters. m.
Specification
1. Remote sensor on the thermal head.
2. Mixing valve.
3. 3/4 tap.
4. Futorka 1-3/4.
5. Tee 1 in.
6. Nipple 1 in.
7. Circulation pump.
8. Valve cock on 1-1/2 manifold.
9. Plug from outside thread 1 inch.
10. Manifold complete with 1-1/2 taps.
11. 16-1/2 pipe and manifold connector.
12. Metal-plastic pipe.
13. Union nuts for pumping.
14. Thermal head sensor.
Let's consider some elements that can be added to the scheme:
- Secondary circuit balancing valve allowing hot and cold adjustmentreturn water. The valve is turned with a hexagon. In order to securely fix it and prevent displacement, it is installed with a clamping screw. It is worth noting that in most cases it has a scale to measure bandwidth consumption.
- Shut-off valve for the radiator circuit, performing balancing functions. It is necessary to connect the mixing unit with other parts of the heating system. You also need a hexagon to turn it.
- Bypass valve. A kind of fuse that protects the circulation pump in the event of a lack of water passing through it. Its operation occurs after the pressure in the system drops to a certain value.
Let's look at how the connection diagram of mixing units looks like
It should be noted that the schemes differ in the principle of the heating system, there are single-pipe and with two pipes. Suppose there is a one-pipe system, in which case the bypass device must be constantly open. This is necessary in order for a certain amount of hot coolant to be able to approach the radiators. If there is a two-pipe system, then the bypass device will be permanently closed, since there is no need for its operation.
A small note: the manifold group does not have to be located before the radiator circuit. After all, if we take into account that the heated house is small in size, then the temperature of the coolant will not be able to keep up withfall while moving through the pipes. Therefore, the collector unit can be installed in the opposite direction from the radiator circuit.
Cost of finished node
Of course, you can not suffer, assembling a mixing unit with your own hands, and purchase a finished product. After all, such a task will require a thorough study of various schemes of work. Ready-made units can be easily found in hardware stores, for example, the Combimix mixing unit from V altec. However, we must prepare for the fact that the price tag is unlikely to please the buyer. Although such a price is justified: buying a ready-made assembly will help protect the consumer from errors in calculations, assembly and installation.
Let's say a few words about the most popular manufacturer of mixing units in Russia - the Italian company V altec. A set consisting of a mixing unit and a pump will cost about fifteen thousand rubles. The American analogue from the manufacturer Watts Isotherm will cost about the same money. Those who are not afraid of difficulties and who have free time can try to assemble a mixing unit with their own hands from different parts.
Conclusion
After the whole complex of installation works is completed, it is necessary to connect the mixing unit to the circuits. In this case, special fittings and adapters will be excellent helpers. And it is very important to balance the system before the first start.
So, we found out how the mixing unit is installed and what this element is. Note that such elements cost about 13-16 thousand rubles.
