Table of Contents
One of the most modern heating systems, so-called “heat-insulated floors”, is known to everyone. It is presented by several options which are based either on water, or on electric heating. And if electricity can be applied in any rooms, then water it is impossible to use in apartments with the centralized heating.
In this article we will consider everything, as for electrical cable systems which can act also as the main heating and as additional heating of floors.
Such systems can be installed together with any types of other heating appliances. Intend for thermal comfort which is especially important for rooms with cold floor (bathrooms, pools, kitchens, bathrooms, etc.) and also for the first floors of the building. “Heat-insulated floor” allows to distribute comfortably indoor temperature and also to warm it during the autumn-spring period when the main heating does not work.
The system is made by heating sections (one section can be used), mounting tapes, temperature regulator, and the protective corrugated pipe intended for the temperature recorder (when it is established directly in floor tie). Mounting is made by means of heat insulation and cement and sand mix (there are special mixes which are intended for “heat-insulated floors – better to use them).
Represent fixed length piece of heating cable with the mounting ends connected to the power supply network. End seal and position of joints of the mounting ends and cable are carried out in hermetic final and connection sleeves. Couplings differ in high reliability and are repeatedly checked industrially.
The system can use either two-core, or single-core heating sections. Both types of sections, but in rooms in which people are the most part of time (nurseries, bedrooms, etc.) are suitable for heating of rooms, it is better to apply two-core sections. Externally, for convenience of distinction of capacities and types of sections, they are differently marked and painted in different colors.
When choosing the producer it is necessary to pay attention to compliance of heating cables to the IEC standards developed by the International electrotechnical commission. They are tested and made on special process. The producer of cable has to have Sanitary and epidemiologic conclusion, the certificate of conformity and the Certificate of fire safety.
One more nuance which has to be considered – cable lay-up. So two-layer isolation usually is exposed to special processing thanks to which becomes not melting and nonflammable. The braided shield intends for increase in thermal stability and ensuring electric and mechanical protection of cable.
Heating two-core sections represent cable, two connection sleeves and the mounting ends. In connection sleeves screens and heating veins connect to the mounting ends connecting heating section to grounding and temperature regulator.
In order that it is correct to connect section, it is necessary to pay attention to coloring of wires of the mounting ends. Black (or flavovirent) connect to the protective shield, and black – to temperature regulator. Protective grounding is connected or to zero conductor, or to the grounding contour.
Heating two-core sections represent heating cable with connection sleeve and the mounting end on one party, and the end sleeve which does not have conclusions on another.
Two-core cable lay-ups allow to give power supply not from two, and since one end. Such option simplifies the layout of cable indoors. Wires in the mounting ends also differ on coloring: brown and blue connect to veins (connecting and heating), connected to temperature regulator, and flavovirent to the protective shield of cable and to zero conductor or ground loop of the building.
Intends for mounting of heating sections on draft floor and simplification of their layout. On mounting tapes there are fixing lobes located through equal intervals, they allow to keep constant step of the layout.
Intends for power saving and comfort of use of heat-insulated floors. Thanks to temperature regulator tension in section will move only if necessary. Programmable temperature regulators allow to set programs which will regulate temperature for day or week.
Let’s consider features of some temperature regulators which are most often used in similar systems.
RoomStat 110 is supplied with the separate switch, is completed with the thermoresistor installed in floor – the temperature recorder. Can be established in multinested wall frame together with other devices. Load current – to 16 A. Saves up to 30% of the electric power spent for heating.
I-WARM 710 is supplied with two temperature recorders – the built-in air-temperature sensor and portable floor temperatures. Intends for the built-in device, provides the set temperature according to indications of the temperature recorder of floor. Has the big highlighted graphic display supplied with adjusting buttons, shows condition of heating (on/off), gives opportunity of regulation of the set temperature, has self-diagnostics and brings the warning information to the display. Has the additional modes: management of heating on time without temperature or on its indicators. The condition of heating can automatically be regulated in percentage. Works with maximum load in 16 A. Saves not less than 30% of the electric power.
I-WARM 720 – programmable temperature regulator, the temperature recorder of floor portable. Reduces electricity consumption thanks to the fact that comfortable temperature is maintained only if necessary or in certain intervals of time. It is equipped with the highlighted graphic display with adjusting buttons, the built-in menu for management of any functions, multimode temperature regulator which the block of real time and the calendar, is built in by the built-in economizer. Collects and saves information relating to heating. The software is “intellectual”, implements several ways of management of condition of temperature:
- support of stationary comfortable condition;
- sets daily cycle of distribution of work of heat-insulated floor. It is enough to user to set time intervals for obtaining necessary temperature. The device independently defines condition of indoor temperature and calculates time necessary for achievement of obtaining the set parameter in due time. In the rest of the time the heat-insulated floor is switched off and does not spend the electric power;
- similar to daily allowance, the week cycle, randomly programs temperature for every day.
PT007L 16D is applied when the power of system is higher than the built-in relay of temperature regulator. It is used when heating big rooms with several established sections or when heating several rooms in one thermal mode. Manages the actuators of groups of sections expected big current.
Heat insulation reduces the losses of the electric power spent for heating of soil, overlappings, designs which lie under the warmed room. Saves 10-30% of the electric power.
The main requirement imposed to thermal insulation material – low heat conductivity, not below than 0.05 W / (m°s). If to use heat-insulated floor as the main heating services not lower than 30 millimeters of thickness covered atop with aluminum foil with thickness are the best of all to apply firm grades of expanded polystyrene it is not less than 0.3 millimeters also polymeric protective layer.
Application of heat insulation from frothed materials with thickness of 3-10 millimeters is admissible. For improvement of heat-protective qualities such materials have to be covered with foil, and for increase in durability — polymeric layer.
Heat insulation is necessary always if floor is on the first floor or close to soil. If floors directly adjoin to soil, it is the best of all to use thick plates from mineral wool or polyfoam.
Arrangement of heating sections
Sections have to be laid so that over cable there were no pieces of furniture without legs closing floorage.
Power density of section has to be calculated proceeding from scope of application. If use of heat-insulated floor means it as the main heating services, power is 130-150 W/sq.m if it is additional source of heat, then 110–120 W/sq.m
The space occupied by the laid heating sections intended for the main heating occupies not less than 70% of the total area of the room. The heating section has to be selected taking into account problem of heating and features of the room.
The same section cannot be used in rooms of different type (for example, for the bathroom and corridor or for kitchen and the hall). It is impossible to apply the same section and in rooms which floors have different design. In this case under each of types of covering it has to be established separate sections with own temperature regulators.
Electrical wiring, arrangement of temperature regulator
At first it is necessary to find out, connection of heat-insulated floors to the available electrical wiring is admissible whether it will sustain loading both from heating of sections and from the additional, already available, electric devices. Also it is specified what current is admissible for safety devices. The system of heat-insulated floors with the power beginning from 2 kW is connected via the separate automatic machine and special wiring.
The heating system through DPS (device of protective shutdown) is connected operation of which happens at 30 mA. Such device is mounted directly on electroguard.
When mounting heat-insulated floors in rooms with the increased humidity screens of heating sections are connected to the grounding contour together with all available metal parts: frameworks of shower cabins, shower pallets, metal body of bathtubs.
The temperature regulator is mounted in wall in the places free from furniture. The systems warming wet rooms have to have the temperature regulators which are taken out out of rooms.
Mounting of system
Consists of several consecutive actions:
- In wall the space for thermostat setting is prepared;
- Make grooves for laying of electrical wiring, installation of the mounting ends and tubes of temperature recorders;
- The surface of floor is cleaned from garbage and leveled;
- The heat insulation keeps within;
- Pieces of mounting tape are fixed;
- The heating section keeps within and fixed;
- The temperature recorder is mounted;
- The temperature regulator is established;
- Electrical connections are carried out. Heating sections and the temperature recorder are checked for potential damages. Resistance of the sensor and section is measured.
- The system is filled in is cement sandy tie;
- The finishing decorative coat keeps within.
The system is finally ready to work after drying of tie approximately in 28 days.
Mounting of heating sections
Sections keep within floor. In need of laying of several sections, the area breaks into sites which correspond to the power of each of them.
The draft floor prepared for mounting of sections should not have hollows, flows and cracks. The sandpaper surface at first is leveled by means of the leveling mixes. After that on surface pieces of mounting tape fasten. They gain a foothold in places in which loops of heating section come to an end. If room space is rather big, then fixture is made bucketed in 2-3 meters.
The mounting end is brought to the place in which the temperature regulator is located. Connection sleeve together with the initial site of section gain a foothold on floor in the place of the beginning of laying of section. The cable has to keep within without intersection, evenly with strict observance of constant step on all plane of the warmed floor. The step of laying is calculated depending on the power density of system according to formula:
- L – the section length specified in the passport,
- S – actual area of laying.
The deviation from rated step should not exceed ±10 millimeters. Rounds of cable should not approach on distance less than 80 millimeters. The ends of loops of cable are fixed by the uvulas of mounting tape bent around them by speakers. Bends of loops should have no breaks, the cable should not be tense. If the warmed area adjoins wall, then the distance from wall to cable has to be approximately equal to 5 centimeters.
End and connection sleeves are located on floor surface. The mounting ends are removed either in terminal box, or to temperature regulator.
The cable is located so that from it to other heating devices (batteries, pipes and struts of heating) there were not less than 100 millimeters. Not to allow mechanical damage of elements of section, laying needs to be made in footwear with elastic soft sole or after laying to cover surface with plywood or other similar materials.
Thermostat setting and temperature recorder
Temperature recorders are installed in corrugated plastic pipes of 14-20 millimeters in the diameter. On the one hand tubes the connecting wire is removed, and the sensor has to be near other its end. The tube is entered into floor, at the same time the radius of its bend should not exceed 5 centimeters. The end terminating in floor densely is closed that the cement slurry has not got to it. From sensor installation site (the end of tube) to wall there has to be distance in 50-60 centimeters. By means of lobes of mounting tape the tube is fixed between section rounds in the middle between two rounds.
After the tube is fixed on wall and on floor, it is necessary to be convinced that in it the sensor can freely move. For this purpose the connecting wire of the sensor is partially pulled out, and then inserted back. Afterwards it will help to replace the sensor without opening of floor.
After that to the temperature recorder, heating section and power line the temperature regulator is connected (mains voltage at the same time is surely disconnected!). Then inspection of operability of system is carried out. For this purpose quickly mains voltage moves. As a result on the panel of temperature regulator the LED has to light up. Upon termination of check it is powered off already before final start of system.
The arrangement of the temperature recorder, temperature regulator and heating section is caused on the plan of the room. The locations of couplings are separately noted.
It is cement sandy tie
Before laying of tie the heating cable has to be fixed by the hills of cement slurry 10-12 millimeters high laid along it. Such precaution is necessary to prevent its shift or damage when laying tie. After that floor is filled in with tie solution. Its thickness over heating sections should not be less than 3 centimeters and if the heat-insulated floor plays role of the main heating, then it is not less than 5 centimeters.
Features of mounting
If the heat-insulated floor keeps within as the main heating services, at first 30-80 millimeters of rigid heat insulation are mounted, afterwards – 5 centimeters are cement sandy tie and already then mounting tape. Other actions continue as they are described above.
Mounting of single-core sections happens similar to sections two-core, but both mounting ends are connected to temperature regulator.
If the section passes through thermocompensation seam to avoid cable damages, it is passed through sand-filled pieces of steel pipes.
Operation of system
The system can be included in network only after the tie finally hardens. The thermometer turns on and desirable temperature is set. During the first inclusion the maximum level which decreases after comfortable temperature is reached can be set.
The feeling of heating of floor during the first inclusion can appear through certain period, sometimes this time lasts up to 2 days. Especially it can be carried to rooms of newly-built buildings with idle heating.
If the heat-insulated floor was assigned as additional system, then its power can not be enough for full heating of the room at the disconnected main source of heat.
Councils and notes
Automatic control of temperature allows to consume to system exactly necessary quantity of the electric power. Also temperature regulators if they are established in each room help to save electricity.
If the long absence of residents in cold time is planned, you should not turn off heating completely. It is enough to establish the minimum level of heating. Energy will be consumed a little, but the room completely will not be frozen, and upon return of it will be possible to warm up much quicker.
Costs of heating by means of correctly picked up systems will allow to save up to 50% of the means spent for heating of the room.