What heating cable to choose for an electric floor heating?
Many people believe that to electrically heat a room, you can simply place a heating cable for a warm floor under the flooring. But here we must take into account the existence of varieties of heating wire. Moreover, in some cases it will be easier and cheaper to lay a heating mat. To find out which is better to choose a heating circuit for your room, let's take a closer look at their variations.
Types of heating cables
For arranging a heated floor there are several types of cables that differ in technical characteristics:
- According to the type of wire, the heating cable is divided into resistive and self-regulating. A resistive-type heating element creates the same temperature on any part of the cable, which is not always convenient when covering the surface of the floor with furniture or household appliances.Self-regulating heating element can react to the ambient temperature, which allows you to independently change the temperature on any part of the wire.
- Resistive type heater can be single and double. The design of the first type of cable during installation requires the return return of the second end to the thermostat to close the electrical circuit. Strong cable is enough to connect one end to the thermostat, which is very convenient for complex room planning.
The strong and single-conductor resistive wire consists of a heating conductor protected by a wire or foiled sheath. Only the design of the first consists of one heating core, and the design of the second cable includes two heating cores. The main difference between the cables lies in the material that was used for the manufacture of the core. To do this, can use copper, brass or nichrome. Each metal has a different indicator of electrical resistance. Most often in production they use nichrome. It allows you to create a more suitable level of heat dissipation throughout the cable.
Resistive cable is characterized by uniform heat transfer along the entire length. This feature may lead to overheating of a separate section. For example, a certain part of the floor, closed furniture. When designing the location of the heating circuit, in such places it is necessary to reduce the amount of cable or, in general, remove it from there. This drawback will not allow in the future to move the furniture to another location.
In order to understand which cable is better to choose, besides its resistance, attention must be paid to the total length and the allowable distance between the heating elements of the circuit laid on the floor. These parameters will help to ensure uniform heating of the surface:
- The permissible distance between the heating elements is indicated by the manufacturer of the product. Non-compliance with the recommendations threatens with the manifestation of temperature differences in certain parts of the electric floor heating. That is, there will be a so-called "zebra". Usually, the manufacturer recommends keeping the pitch no more than 120 mm.
- The cable is sold for a certain length, which requires proper calculation of the circuit. When installing add the missing piece or cut off the excess part will be impossible.
Another important parameter that you need to pay attention to when choosing a cable is the number of heating wires.
Single core cable
A single-core type of cable during installation requires that both ends of the cable converge in one place to close the circuit. The design feature is the presence of two unheated ends connected to the thermostat. Single-core cable has several advantages over other types:
- the limiting heating temperature is much higher than the two-core type can afford;
- low power consumption;
- low price of the product.
The general installation scheme consists of the following items:
- The end of the cable that is not heated by electric current is connected to the thermostat.
- The contour is placed on the floor according to the scheme.
- The second “cold” end is returned for closing the circuit and is also connected to the thermostat.
Preferring a particular type of heating element, one should know that it is better to choose a single-core wire for public premises or non-residential rooms. Homes suitable rooms can be a kitchen, toilet, bathroom or corridor.
Two-core type of heating element does not require return when installing the second end of the wire.The circuit is closed due to a coupling mounted on one end of the circuit. The two-core wire has its advantages:
- the simplicity of laying the wire, which does not require the return of the second end, makes it possible to form a thermal route of any complexity
- one-way switching to the thermostat;
- An electric current passing through a two-core wire does not change the electromagnetic field.
The loop connection sequence consists of the following actions:
- A special coupling connects the electrical circuit at one end of the wire and connects it to the thermostat.
- The contour is laid on the floor according to the scheme.
- The conductors of the second end of the wire are simply connected to each other and insulated.
Due to its advantages, a twin wire is better to choose for living rooms, for example, a bedroom or a hall.
Good technical characteristics has a self-regulating cable. Its design and principle of operation differ from its predecessors. The wire consists of two conductive wires in contact with the polymer matrix. It is this semiconductor matrix that regulates heating itself due to its properties.The fact is that increasing the temperature lowers the conductivity of the semiconductor, naturally, this reduces the thermal power. On top of the matrix is protected by two insulating shells, between which there is a screen braid.
For clarity, let's take a closer look at the principle of operation of a self-regulating heating wire:
- lowering the temperature of the air in the room leads to compression of the middle of the cable, which increases the strength of the current and increases heat generation;
- an increase in room temperature causes a backlash with a decrease in current. Naturally, the amount of heat released is reduced.
Self-regulating heating wire has a lot of advantages over its counterparts:
- the ability to independently change the heating power when changing room temperature;
- reliable multi-layer protection against mechanical and other damage;
- The design features of the wire create protection for the electric floor from overheating. This extends the service life of the heating element, without requiring its frequent repair.
The technical features of the electric heater allow the use of wire in any room,not taking into account the design features of the floor and furniture location Each section of a warm floor will maintain the desired temperature. If a part of the heater reaches a certain temperature under the furniture appliance, it will turn off before cooling, and the rest of the circuit will continue to heat up. Self-regulating wire is better to choose a living room for the electric floor under the tile.
The only downside is the high cost. The price of 1 m of the wire varies from 5 to 10 $.
Arrangement of a warm floor with electric mats
Heating electric mat is very convenient for arranging underfloor heating with minimal costs. Mat is carbon and cable. Between themselves, they differ in technical characteristics, installation, materials of manufacture and the principle of heating. The only similarity is their layout. Any mat resembles a track rolled into a roll.
If you take a closer look at the device, you can see that the cable mat is the same resistive single-core heater attached to a reinforcing mesh in the form of a snake. Such a heater is well suited for tile, as the thickness of the whole “cake” is approximately 30 mm.
The heating mat is rolled on the old floor covering.The main thing is that it should be smooth and clean, as the roll fixing occurs due to the adhesive backing of the film. Mate roll around the room, starting from the thermostat. When cornering, only the reinforcing mesh is cut, and the wire itself, together with the cut mesh, is turned at the right angle. Next, install the thermostat, lay the wire in the corrugated hoses and stick the mat to the base. After checking the efficiency of the heater on top of the stack tile on the adhesive solution.
The carbon mat design has rod heating elements connected in parallel to each other. Special material tires under the influence of electric current allows them to emit infrared radiation, which is a source of thermal energy.
Each rod operates autonomously, independent of each other. If one element fails, the infrared mat continues to operate. Rods tend to independently regulate the heating according to the principle of self-regulating cable. When the maximum temperature is reached, the rod is locked, which provides energy savings and protection against overheating.
Infrared mat is also better to choose for laying under ceramic tiles. Roll roll around the room like a cable mat. Only the infrared mat is laid on the insulation with a reflective coating. It will provide a reflection of heat up. They are attached to the floor with adhesive tape or glue. The tile on top can be laid in two ways:
- First, a 20 mm concrete screed is made, and after it is dried, tiles are laid on top of the glue;
- without additional screed, tile glued to the infrared mat with glue. The thickness of the adhesive layer must be at least 20 mm.
Usually, tiles are immediately glued in the kitchen or bathroom. It is common for the hall to make a screed, then glue the tiles.
The heat-insulated floor from an electric film mat is the same infrared floor, only a little differing in the features. In this material, carbon rods are sealed in a polymer film. They are afraid of overheating, so their installation, like mats with resistive cables, is impossible under installed furniture.
The principle of installation is the same as for other mats, only on top of the film mat is covered with a windproof non-woven material.After that, proceed to laying the flooring. If it is planned to lay laminate on top, the substrate can replace the windscreen. Under the carpet or linoleum film mat cover with plywood or chipboard, but the tiles can not be laid on top. This is due to the fact that the adhesive composition does not stick to the film. Although, some inventors manage to cover the heater with a waterproof plasterboard or reinforcing screed, and to lay the tile on top.
Features of connection of an electric heat-insulated floor
Regardless of the type of heating element, a three-core cable is used to connect to the power grid and additionally install an RCD. Protection will save the system from mains voltage surges, and a three-core cable is necessary for a mandatory ground connection.
The temperature of the electric floor depends on the sensor and programmer. These devices set the required heating. But we must remember that each heating cable for a warm floor has an optimal temperature, which should not exceed its limit:
- Maximum cable temperature is 65aboutC, but usually they work at an average temperature of - 30aboutFROM.Protective insulation stand no more than 100aboutFROM;
- The operating temperature of the electrical mat depends on its grade. It usually ranges from 80 to 104aboutC. For example, the temperature of the cable mat is a maximum of 60.aboutC, and carbonic - 55aboutC. The maximum operating temperature of the film mat is 55aboutC, although the film itself can withstand up to 250aboutWith, then begins to melt.
There are many ways of electric floor heating. In each case, the choice of heating element must be made individually, taking into account the type of flooring, floor design features, installation complexity and other factors.