A warm water floor in an apartment or a private house is a modern solution that provides residents with the maximum level of comfort. The organization of space heating using underfloor heating systems has a number of key advantages compared to traditional radiator heating:
1) Thanks to the large area of the heat-radiating surface, the heating of rooms is very fast and at the same time uniform. You can walk barefoot on warm floors without discomfort, children are guaranteed not to catch a cold while playing on the floor.
2) Bulky heating radiators do not take up space near the walls, which eliminates problems with the arrangement of furniture. Their absence also allows, if desired, to install floor-to-ceiling panoramic windows in the room). The risk of injury or burns on the surface of the heating device is reduced to zero.
3) The heat flow is strictly vertical, which excludes the circulation of dust and harmful microorganisms around the room. People who are often prone to viral diseases, as well as those who suffer from allergic reactions, are much more comfortable in rooms heated with water-based underfloor heating . The even distribution of heat from the floor to the ceiling also prevents the upper layers of the air in the room from overheating and significantly reduces heat loss through building floors and upper parts of walls.
4) The temperature of the coolant in underfloor heating systems usually does not exceed 35-40ºС, which leads to a significant saving of energy used for its heating.
General information on the construction of water-based underfloor heating systems.
The water heated floor system consists of the following main components:
- Regulating and shut-off fittings
- Pumping and mixing module
- Collector module
- Pipelines made of polymer materials
- after-use fittings
- Indoor temperature control systems (thermostats)
A boiler operating on any type of fuel (diesel fuel, gas, electricity, firewood, coal) can be the source of energy for underfloor heating. The best energy-saving results can be achieved when using low-temperature heat sources (sacramento water heaters, heat pumps).
When heating rooms with warm floors, an interesting effect occurs: according to the laws of physics, the greater the temperature difference, the stronger the heat is transferred from a warmer object to a colder one. As a result, when the air temperature in the room increases, heat extraction from the water-based underfloor heating system decreases. For example, as soon as the day came and the sun warmed the air in the room by several degrees, the heat flow from the floor surface automatically decreased, and vice versa, when night came and the sun hid behind the horizon and the temperature in the room decreased, the heat flow from the floor surface naturally increased This phenomenon was called the “self-regulation effect”.
In more detail, we will consider the main ways in which pipelines and underfloor heating systems can be filled with a coolant:
1) Direct connection to the boiler. To organize the circulation of the coolant to the underfloor heating circuit directly through the boiler, the latter must necessarily have the function of working in low-temperature mode (in the range of 35-55°С). Due to the low temperature of the heat carrier in the system, the same boiler will not be able to “feed” radiator heating or the domestic hot water system, i.e. the boiler will work only for heating the premises with the help of the “water warm floor” system, but it will also consume much less fuel than boiler operating in traditional mode.
In case of such a connection, maintenance of the set temperature of the heat carrier of the underfloor heating circuit will be carried out automatically directly by the boiler itself.
2) From the boiler through a three-way mixing valve with a thermal head (with a remote sensor) or a three-way thermostatic mixer.
Creation of a low-temperature circuit and maintenance of the set temperature of the heat carrier of the circuit of the warm floor is carried out automatically by a three-way mixing valve with a thermal head (with a remote sensor) or a three-way thermostatic circulation in the circuit of the warm floor is provided by an additional pump.
The boiler with this scheme of operation heats the coolant to a significant temperature, which allows it to be used simultaneously with the “warm floor” for radiator heating or hot water systems (using indirect heating boilers). For warm floors, the required coolant temperature (35-40ºС) is achieved by automatic mixing of cooled water with the help of one of the valves listed above.
With greater versatility, compared to the first method (a boiler with a normal temperature regime is suitable, traditional heating and hot water supply can be organized in parallel), the negative side of such an organization of heat supply to the circuits of the warm floor is a high probability of incorrect installation, as well as a strong dependence on the cross-section of the valves . Each valve has a maximum throughput, which limits the possible area of rooms heated by warm floors.
3) From the boiler through the pump-mixing unit.
With this method of connecting the underfloor heating system to the boiler, the organization of the low-temperature circuit and maintenance of the set temperature of the heat carrier is carried out automatically by the pump-mixing unit. It usually includes:
- The regulating valve is three-way
- Circulation pump
- Measuring devices (thermometers)
- Air deflector
- Shut-off and regulating fittings
The key point that distinguishes this method of connecting circuits is the presence of a circulation pump in the kit. It is almost impossible to install the underfloor heating system using such a unit incorrectly, which means that there is no reason to worry about the efficiency of the system. Depending on the power of the pumping and mixing unit, the maximum area heated by “warm floors” also varies.
Underfloor heating is organized by laying pipelines in the base of the floor, which can be of the deck or concrete type.
The term “floor” refers to wooden coverings, which are boards, plywood or simply wooden beams, on which the pipelines of the underfloor heating system are placed. As a rule, this method is used in cottages from the second floor and above, when there is a need to reduce the load on the ceiling or the thickness of the “pie” of the warm floor. The strength of such a floor is given by 2 gypsum fiber sheets (GVL), between which are placed polystyrene foam panels with grooves for laying pipes of a water warm floor.
The concrete base of the warm floor (concrete screed) is the most common and most often used. The surface of the base must be clean and flat, protrusions of more than 10 mm are not allowed. Leveling of the base under the concrete screed is carried out using a thin layer of cement-sand mortar or dry sand.
There are many ways of laying a “warm floor”, but they all boil down to one thing: first, heat insulation is laid (perhaps with a reflective screen), then the loops of the “warm floor” pipes, a screed, and a covering on top (tiles, special laminate, etc.). It is necessary to apply a damping tape around the perimeter of the room, the purpose of which is to protect the walls of the house from the mechanical impact of the effect of thermal expansion of the floor surface.
Before laying a layer of thermal insulation, you should make sure that it is not recommended for this project of the house to install steam or waterproofing in the floor structure (for example, the concrete preparation of the floor is made on the ground, or the floor is made in the bathroom). If this is provided for in the project, then a layer of steam or waterproofing of the roll, bulk or coating type is laid on the base cleaned of debris. If bitumen-based materials are used as insulation, then the bitumen must dry completely before laying thermal insulation from polystyrene foam boards.
The efficiency of the floor heating system largely depends on the correct choice of thermal insulation. It is necessary to minimize the loss of heat due to the overlap, thereby maximizing the efficiency of using the thermal energy produced by the boiler. Most often, ready-made insulation boards, made specifically for “warm floors”, are used. When installing insulating plates, it is necessary to ensure that there are no gaps between them, so that the screed solution does not penetrate between the insulation plates and does not create temperature and acoustic bridges.