If for many of us the systems of "warm floor" were quite recently a wonder, now few people can be surprised by them. They are used in conjunction with central heating in the form of additional heating or without it, they are used for the whole room or only in certain rooms, for example, in the bathroom.
These systems are considered low temperature, while conventional radiator heating is considered high temperature.
Underfloor heating manifold
What is a mixing unit for?
If a temperature of 80-90 degrees is required for conventional heating with batteries, then for floor heating it should be lower, 30-40 degrees, so that it is comfortable to walk on the floor without the risk of burns. It is with the help of a mixing unit for a warm floor that favorable conditions can be obtained for the full operation of invisible heating elements.
The mixing group for underfloor heating is a key component of water heating devices.
Systems of this type make it possible to connect a collector unit that provides the necessary combination of water at different temperatures to obtain favorable conditions in the room. But the use of such a device as an independent control device is not excluded.
The pipeline is equipped with a small pump, by which the forced circulation of the heat source along the circuit is carried out. These devices have supply valves with two or three strokes. They are necessary to obtain a constant addition of cold liquid from the circulation to the coolant.
Installation of a water-heated floor in a concrete screed
The process of installing a water-heated floor with a screed:
Cleaning and leveling the surface After cleaning, check the surface of the base for differences in height.
If the difference does not exceed 1 cm, you can start laying the floor. If the difference is 2 cm or more, you need to level the surface. A self-leveling floor is best suited for this.
How to make a self-leveling sub-floor, we wrote in previous articles.
- Waterproofing. A waterproofing film is laid in order to protect the coolant from possible moisture from below.
- Edge insulation. Along the perimeter of the walls, a damper tape is laid and attached to the entire height of the future floor.
- Thermal insulation. Insulation 1-5 cm thick (depending on how warm the floor you make, and what climatic conditions) should be slab. You can also buy insulation with a reflective surface.
- Reinforcement. It is advisable to buy a reinforcing mesh with cells of 15-20 cm: it is easy to lay a pipe of a water-heated floor over them.
Many people make reinforcement before laying the pipes of the water floor, but it is advisable to do this after, since in this case the reinforcement will evenly distribute the load on the pipes.
Laying a water-heated floor. First, we connect the pipe to the outlet of the supply manifold.
If you are making a warm floor as the only source of heating, then lay the pipe with minimal indents directly along the grid (the step between the pipes is 15-20 cm). If the warm floor is an auxiliary heating system, then the laying step can be up to 30 cm, but no more. The fastening of the pipe to the mesh is made very easily with special clips (the step of fastenings is about 1 meter), but there is no need to rigidly fasten it: the pipe may expand slightly from heating.
You can also fasten the pipes with fixing strips (track) or strings.If the installation goes before the reinforcement, then there are special clips for fastening to the base. If you are laying the floor in a snail pattern, do not forget to reverse.
The optimal pipe length for one circuit is 70-80 m. If this length is not enough for one room, divide the area into 2 circuits. For a room with an area of 10 m2, with a step between pipes of 15 cm, the length of the pipe will be 67 m (just the best option).
After laying the entire length of the pipe, we connect it to the outlet of the receiving manifold.
Functional check. After the installed water floor heating system, it must be turned on for several hours to ensure the quality of the installation. The pressure should decrease by about 0.03 MPa per hour, while the water temperature should be the same.
Filling the screed. The thickness of the screed of a water-heated floor should be 2-3 cm higher than the pipes or reinforcement. We wrote in one of the previous articles how to make a wet screed.
When the screed is dry (1 month), proceed to the installation of sound insulation and coating. Do not turn on the warm floor until the screed has completely set: the screed cannot be forced to dry - it will crack.
Advantages of mixers
The internal equipment, which has a mixing unit for underfloor heating, has a list of advantages that make this unit productive and in demand. Its main advantages include:
- Economy. Unlike electric hidden heaters, water heaters with a mixer for a warm floor can save up to 60% of electricity.
- Safety. People often forget how high the temperature of the heating element is, which leads to severe burns. The use of a special thermo-mixer allows you to prevent such situations and protect yourself from danger.
- Long service life. The installation of such a heating block is very beneficial in comparison with other devices of similar functions. And if it is laid in accordance with all the rules, then it will last more than 50 years. The coolant is subject to wear, but the manufacturer notes that its service life is at least 50 years.
- Purity. Caring for the invisible block is not difficult and does not require much effort. In addition, due to the fact that the coating is constantly heated, it dries very quickly, which eliminates the risk of mold and mildew.
- Ambient temperature control - the system is equipped with a static thermal valve connected to the regulator. This means that you can adjust the heating level taking into account changes in temperature indicators outside.
- The presence of mechanical control, in which the unit for the warm floor is independently regulated.
- Limit mode application. This allows you to set a suitable room temperature. For example, you set a specific temperature using a thermostat, upon reaching which the system will maintain it at this level, preventing the coolant from overheating or cooling.
Installation of a water heated floor on polystyrene foam mats
It differs from the previous one in the absence of a screed and insulation (which is the expanded polystyrene mat itself). Over the entire area of the mat, at an equal distance from each other, there are tubercles, between which a pipe is laid. After laying the pipes, the mats are poured with a screed, then the sound-insulating material and the floor covering are laid.
Also, laying can be done on expanded polystyrene plates.
But before that, you need to create an installation scheme, since you will be laying the slabs along it. The slabs have grooves in which aluminum plates are laid (for heating), into which pipes are already laid and fastened. After laying and checking the performance of the water heated floor, sound insulation and coating are laid on it.
Types of collectors and their features
The work of type No. 1 is based on a three-way valve for a warm floor, the task of which is to combine a new heat source from a heating boiler with a spent cooled one.
The throttles are equipped with a servo drive, by which the thermostat and weather sensors are controlled. This type is the most optimal, but at the same time it has some disadvantages.
First of all, I would like to highlight the situation when the valve, upon notification of the thermostat, can open in full and run into the pipeline a large amount of hot liquid, the temperature of which varies within 90 degrees.
A sharp jump in the heat source can cause a rupture of the coolant, since the pressure in it becomes too high. Another disadvantage of this method of regulation is the high throughput. This is challenging because any change in temperature setting can affect floor heating.
Even if there are drawbacks, hidden heating with a device of this type is considered an indispensable assistant in heating rooms with a large area.
View No. 2 is equipped with a two-way control valve. Unlike the previous version, the combination of a heat source is not performed upon notification of the thermostat, but in a constant mode, which prevents the risk of an increase in the set temperature regime of the floor.
Moreover, the thermostatic 2-way valve has a small flow capacity, which allows uniform and stable regulation of temperature conditions. But at the same time, experts do not advise installing invisible heating devices equipped with such a system in rooms larger than 200 m2.
How does automation work?
The thermostatic three-way valve for underfloor heating is connected in front of the manifold. A certain temperature mode of heating is set on the sensor. The device starts working when the parameters are changed.
- The device consists of a semiconductor that has the temperature of the coolant entering the line. Energy is transferred to the thermostat fluid.
- With an increase in heating, the liquid expands and presses on the stem, which is lowered.
- This closes the outlet from the hot pipe and opens the outlet from the return circuit.
- The cooled heat carrier enters the chamber of the three-way mixer, where it is connected with hot water from the boiler. The mixing process can take place in a T-shaped pattern: hot and cold coolant flow enters the thermostatic mixing valve symmetrically from both sides. The liquid exits into the main line at an angle of 900. In the L-shaped scheme, hot water enters the mixing chamber from the side.
- The temperature of the heating medium decreases. It enters the floor line cooled down. Heating mode tends to reach the set rate.
- As the temperature drops, the liquid in the thermostat narrows. The spring-loaded stem is straightened, the outlet of cold water is closed, which goes through the return pipe. The hot coolant again enters the line.
When using servo drives, a device that works from the mains is connected to the mixing valve for the underfloor heating. The sensor heats up, closes the electrical circuit. The plate heats up, which in turn transfers heat to the thermal fluid. It expands, presses on the stem, which makes the poppet valves work.
When using a servo drive, the heating system changes the operating mode within 3 minutes. If a thermal head is used as an automatic device, then it will take up to 15 minutes to heat the liquid in the thermostat.
The principle of operation of a two-way valve for underfloor heating is somewhat different.When the temperature in the line rises, the thermostat makes the poppet valves or a ball device work, which completely blocks the outlet for hot water. The cooled heat carrier from the return pipe returns to the floor circuit.
Manifold distribution unit
The collector is one of the important parts of the heating system, which is responsible for adjusting the mode of the heating element. The main task of this device is to distribute the heat source along the pipeline.
And in order to get a full and productive work of the collector, you need to equip it with thermal valves and a flow meter. If you resort to the help of specialists who install the valtec floor heating mixing unit themselves, they will select all the necessary accessories for installing the manifold block.
Installation steps
All measures for connecting such a device must be carried out by specialists. In addition, many companies that sell mixing units and underfloor heating systems, as well as a mixture for underfloor heating screed in Moscow, offer their installation services, giving a long-term guarantee.
But if you decide to connect a mixing underfloor heating yourself or are simply interested in how to connect it correctly, then our information will be useful.
So, all activities are divided into 5 stages:
- The place for the collector is identified and the supply and return pipes are supplied.
- The valves and the manifold for the underfloor heating are connected, after which preparation for the installation of the circuit is carried out.
- All connecting temperature and pressure sensors are installed.
- Then the mixing unit for the underfloor heating is set up with our own hands and several test starts are performed to check the correct operation of the device and the entire system.
- The system is tested for air tightness. In the absence of leaks and correct operation, the installation is considered complete.
conclusions
The mixing valve is the main element of the underfloor heating control system, which directly affects the flows of hot and cooled heat carrier and maintains the operating temperature of the system. The action of a two- or three-way tap is the most critical function of the mixing unit, the quality and accuracy of regulation of the operating mode of the heated floor depends on it.
The importance and significance of the device requires increased attention to its performance, otherwise malfunctions in the operation of the entire heated floor, fraught with the cessation of heating at home, are possible.
To date, among the systems used for heating residential premises, a significant place is given to warm floors. In terms of the complexity of the design and the method of installation, the warm floor can hardly be called an easy and affordable heating option. Efficiency is another matter. The use of underfloor heating for heating ensures the most comfortable temperature balance in living quarters. Comparing the performance of water floors with traditional radiator heating, the former benefit significantly, both in terms of efficiency and aesthetics. The only obstacle that does not allow the wider use of heating water pipes for floor heating is a significant difference in the temperature of the coolant.
An autonomous boiler or central heating system provides water for heating with a temperature of 75-95 0 C. The underfloor heating is a low-temperature system, the optimal water temperature in the heating pipes of the water circuit is 35-55 0 C. How in such a situation to get water for a warm floor of the required temperature ? The mixing valve for underfloor heating successfully copes with this task. The device mixes hot and cold water circulating in the system, i.e. preparation of the coolant for subsequent supply to the pipeline of your floor. What mixing valves are and what their work is, we will consider all existing models and installation options.
