Heating cables are used to heat water pipes, roofing, eaves and other elements where freezing of water in winter is undesirable. A self-regulating cable has the ability to independently change the heating intensity in different areas depending on the need: the lower the temperature of the heated object, the more the cable heats up.
Self-regulating cable device
A self-regulating cable has two copper cores through which electricity is supplied, between them there is a key device for the entire cable - a conductive heating matrix. Each of its elements is connected to an electrical circuit in parallel between copper power wires. It is this matrix that is the heating and regulating element. On top, the entire electrical structure is wrapped in a layer of thermal protection. Next is a shielding braid that protects the cable from external electromagnetic influences and the cable is grounded on it. And finally, the cable has a protective coating on top that protects it from mechanical damage.
Operating principle of a self-regulating heating cable
The operation of a self-regulating heating cable is based on a simple property of an electric current conductor: when heated, its resistance increases, and the higher the resistance, the lower the current strength, and therefore the power consumed. The section of the cable that is located in a colder place has less resistance; greater current flows through the heating matrix in this section, which leads to greater heating of the cable and more intense heating of the pipe. Where the temperature is higher, the resistance of the matrix is greater and the current flowing through it is less. Thus, when you turn on the self-regulating cable near a freezing water pipe, it turns on at full power, and as the pipe warms up, its power gradually increases.
The heating cable itself does not turn off when the desired temperature of the heated pipe is reached; it continues to work constantly, just with less power. For example, a cable is used on a section of a water pipe at the entrance to a house in winter, and its task is to maintain the pipe temperature of +5 degrees to prevent freezing. The self-regulating cable will not turn off the heating at temperatures of +5 degrees and above, and will not turn on itself when the temperature drops below +5, it will work constantly, just with different intensities. The power consumption of a self-regulating heating cable is about 10 W per meter of length (minimum 5 W, and the most powerful models consume 150 W), this is not much in terms of electricity consumption, and you can afford to simply keep it on all the time in the cold season. But the service life of such a cable is not infinite, so it is unreasonable to use it at positive temperatures when there is no need for it.
To turn off cable heating when it is not needed, you need to use automation - thermostats and relays that will turn on the power to the cable when the temperature drops and turn it off when the pipe is heated.
- Installation of a self-regulating heating cable can be done in different ways: inside the pipe and outside, placed along the pipe or in a spiral.
- Why do you need a hydraulic accumulator? This is a device that is used in water supply systems to store a certain amount of water under pressure and, when the pump is turned off, provides water pressure and the ability to consume water for some time.
- To select a heating cable, you need to understand what technical characteristics you need to pay attention to, as well as understand what your heating needs are. This article will discuss the main characteristics of heating cables for water supply heating needs.
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Water pipes located at depth are susceptible to freezing at minimum temperatures. This leads to disruption of the functioning of the entire water supply system. To minimize the likelihood of such a risk, you can install a heat cable for the water supply. This element can be located inside or on the surface of the pipes. The ability to use heating cables of different lengths allows you to heat the entire system or a separate part of the water supply located in the freezing zone.
How does a heating cable work?
Heating of the cable occurs due to the action of passing current. This heating element is positioned as the main component of the system, providing reliable protection of pipes from freezing. Its operation is based on the conversion of electrical energy into heat.
Plumbing heating cables do not transmit energy. Its main characteristic is specific heat release. General product lengths may vary depending on consumer needs. The cable is distinguished by the presence of a sealed, seamless sheath, which is highly resistant to negative chemical influences and makes it easy to withstand the effects of minimum temperatures.
The main heating element of the cable is located inside the protective sheath. If the ambient temperature drops, it is connected to the network and the pipe is heated. When the temperature increases further, the power is turned off and heating stops. This method of heating the water supply system has a number of advantages:
- efficiency;
- safety;
- ease of operation;
- versatility.
Economical . Using a heating cable for water supply, you can focus on the ambient temperature and coordinate the operation of the entire system. The ability to adjust the heating power allows you to minimize the level of electrical energy consumption.
Safety . The insulation system very well protects the heating wire from various negative effects of mechanical, chemical and thermal types.
Easy to use . To start functioning, simply turn on the power and press the button. The extreme ease of operation of the entire system helps to expand the range of consumers.
Versatility . The design features of the product mean that such a heating cable for pipes can be used to heat any water supply system located underground and on the surface.
Design features
The main functional element of the cable is the inner core. To protect it, polymer material is used. The overall sheath is made of PVC. It provides reliable protection of components.
Cheaper cable variations have a single-core design. Such products are characterized by extreme design simplicity. At the same time, single-core cables do not have an additional current-carrying core, which is present in two or three-core products.
The heat cable for water supply is presented in the form of an electrical tape-type guide. The two-layer structure of the product provides additional dielectric strength, as well as protection against abrasion and shock loads.
Heat Cable Variations
The classification of such products is carried out according to various criteria. The cable can be resistive and self-regulating. There is also another type of product with mineral insulation. Heating of pipes with cable can be carried out using any of the above product variations.
Resistive cable
Heating of the water supply through the use of such a cable is realized on the surface or inside the pipes. Temperature sensors are installed outside the plumbing system. Provided that the temperature drops below a preset level, the heating is turned on. After reaching a certain temperature threshold, the system turns off.
A resistive type heating cable can be linear or zonal. In the first case, we can talk about the sectional design of the product. The zone cable is distinguished by the presence of two conductive elements located in parallel. The top layer of such a product is presented in the form of a spiral of small diameter.
Mineral insulated cable
This cable is based on a copper core. The top layer is presented in the form of an insulator made of magnesium oxide. This ensures stable operation over the widest possible range.
Self-regulating cable
In terms of design, a self-regulating heating cable for water supply has much in common with the resistive variation of the product. However, it is distinguished by the fact that it lacks an insulating coating. Such a heating cable for pipes is capable of locally changing the amount of heat generated.
Features of installation work
Heating pipes with cable allows you to minimize the risk of freezing of the water supply system. Installation work is carried out in two ways, which differ in the location of the main heating element.
Heating cable outside the pipe
The heating cable on the outside of the pipe can be located linearly or in a spiral. In the first case, it is most advisable to place it in the lower zone of the pipe. This position will help protect the entire heating system from mechanical damage.
Installation of a heating cable for a water supply system must follow certain rules. In particular, it is necessary to ensure the most reliable and tight attachment to the pipe. For these purposes, you can use adhesive fiberglass tape or plastic clamps.
Advice! Before direct installation of the heating cable, it is recommended to insulate the pipe with foil. This will ensure the longest and most reliable operation of the entire system.
Heating cable inside the pipe
Internal connection of a heating cable for water supply is a more labor-intensive procedure. Manufacturers provide a complete set of additional attributes necessary for high-quality installation.
The heating cable is inserted into the pipe using special glands. It is strongly recommended to refrain from routing cables through shut-off valves. Also, before installation, care must be taken to remove all sharp edges and threads on the fittings.
It is best to install the section of the water supply system that will be heated by cable with a minimum number of connecting elements. In order to ensure efficient cable operation and uniform heat distribution, it is recommended to take care of high-quality pipe insulation.
Quite often, the plumbing system requires repairs due to freezing of pipes in winter. To prevent accidents, heating is used through a cable installed inside or outside the pipe. Additional heating prevents the pipelines from freezing, and it is not difficult to install the heating cable yourself. The photo below shows how a heating cable is laid around a sewer pipe under insulation.
Heating cable laid around the pipe
Cable device
The basis of the pipeline heating system is a heating element located inside an insulating shell that is resistant to external influences. First of all, it must easily withstand temperature changes.
In fact, the pipe is heated through a cable, which has significant differences from the conductors that transmit energy to the load. The heating cable itself is a load. When voltage is applied to it, the passing current generates heat, which is then transferred to the pipe. In Fig. A diagram of heating a pipeline with a cable laid outside is shown.
Diagram of a pipeline heating system with cable from the outside
The system includes the following parts:
- heating - cables with fastening elements (highlighted in red in the diagram and located along the pipes highlighted in blue);
- distribution - power supply cables (dark blue) and information transmission (green), distribution boxes;
- control equipment - protection equipment, starting control, thermal control with air and pipe temperature sensors.
The heating cable is connected to the network based on signals from temperature sensors. When the ambient temperature rises (usually more than 5 0 C), the cable is disconnected.
It is important to choose the right location to measure the pipe temperature. The sensor is usually placed at an equal distance between the turns of the cable.
Advantages of cable heating:
- ease of implementation;
- possibility of equipping any pipeline;
- economical and safe when executed correctly.
Cable types
The most common is resistive cable. It is cheaper and easy to install. The cable is sold with one or two cores. Heating occurs due to ohmic losses in the heating core. If you install the heating yourself, you can use it successfully. It is used for heating water pipes, sewer pipes, and underfloor heating systems. The diameter of the pipes does not exceed 40 mm.
In Fig. Below are single-core (a) and two-core (b) resistive cables. The first one is the cheapest and is best suited for DIY installation. The disadvantage is that the wire must be returned to the voltage source for connection. A two-core wire requires a coupling at the end.
Single-core (a) and two-core (b) resistive cables
Resistive wire is sold in a specific length. If you cut it into pieces, you will have to reduce the supply voltage. Otherwise, the wire will simply burn out from overheating.
When heating containers and pipes of larger diameter, self-regulating cables are used. They consist of two conductive wires. When voltage is applied to them, current flows from one core to another through a layer of electrically conductive plastic, causing it to heat up. The resistance value of the plastic depends on the ambient temperature, which provides significant energy savings due to self-regulation. Its price is much higher, and it is better to invite specialists for installation.
Do-it-yourself water supply with protection
The street water supply on the site can reach a length of several tens of meters. If the water in it turns into ice in winter, repairs can only be done in May, when the ground thaws.
Heating cable outside
The depth of pipe installation is selected based on the freezing level in the region. The indicator is taken as an average and in some cases it is not enough, for example, under a concrete path or paving stones being cleared of snow. In such places, the pipes are laid even lower, otherwise they will have to be constantly repaired due to freezing. The water supply inlet may be close to the surface of the ground or pass through a cold basement. It is advisable to choose pipes from plastic, for example, HDPE. They are cheap and can withstand repeated freezing.
In order to avoid frequent repairs by replacing pipes, it is advisable to lay a heating cable along with them in difficult areas. Buying an expensive heating system does not always pay off. An alternative could be to use an ordinary field worker for communications - P-274. It has very durable insulation that will not require replacement or repair for years when used in the field. The presence of steel wires together with copper wires in the cores creates additional resistance, due to which the cable can be used for heating. In Fig. Below is a cross-section of wire P-274.
Field wire cross-section P-274
For safety, the P-274 field cable is not connected to a 220 V network. It requires a voltage of about 1-1.5 V per linear meter of cable. If we take it 30 m long, a voltage of 36 V will be required. The current will be 8-10 A, and the temperature will reach 60 0 C. This is quite enough to melt the ice in the pipeline. Power can be supplied from a separate unit with a transformer.
For heating, you can even use a regular TRP telephone wire (Fig. below). It can also be used to heat the fittings if the winding is made more tightly.
The use of telephone wire for heating pipes
The field cable is wound externally onto the pipeline in increments of about 10 cm (Fig. below). Since it is cheap, you can also wind a backup cable, since the next pipe repair will not be soon, and the resource of any home-made devices is usually short. Two heaters can be connected simultaneously if the pipe freezes.
Aluminum tape is wound on top, which allows for more uniform heating of the pipe. Aluminum foil provides better heat removal from the cable and does not allow it to overheat when surrounded by insulation.
In regions with cold climates, it is recommended to wind the cable more frequently. As a result, heating efficiency increases. In any case, the length of the spiral must be at least 1.7 times the length of the heated pipeline. If the pipe heating is installed correctly, it can operate in any weather conditions and will not require repairs for a long time.
Application of field cable P-274 for heating water supply
When water pipes are repaired, they should be insulated. On the one hand, the heat from the cable will not go into the ground, and on the other hand, the insulation protects the pipe and cable from the action of the ground.
2-3 temperature sensors are installed in potentially dangerous places in the pipeline. The soldering areas are protected by heat-shrinkable tubes with sealant. The temperature can be controlled automatically or manually.
The heating cable must be connected to power. At a large distance from the shield, a junction box is used. You can install a transformer in it.
More heaters are attached to the fittings, since more heat is needed there.
Cable from inside
If it was not possible to install a heating cable when laying pipes, it can be placed inside the existing water supply. Cable P-274 is resistant to water. The double wire can be unbraided and one core can be passed into the pipe by bending it in the middle. Then there is no need to expose the insulation to create a connection.
The cable is inserted into the water supply through a tee. To enter it, you can use the filter housing. It is important to ensure the tightness of the input. To do this, a fitting is screwed into the tee. A wire is inserted into it, after which the fitting is filled with epoxy glue of the “cold welding” type. In Fig. Below is a section of pipeline with a field cable wire installed inside.
Installing a heating cable inside a pipeline section
There may be no water in the pipeline. It has been experimentally established that at a current of 9 A the cable heats up to 62 0 C in the absence of water. It can remain in this state for a long time.
Internal installation of the heater has the following disadvantages:
- reduction of the passage opening;
- overgrowing of the conductor with plaque;
- Complicating the water supply system reduces its reliability.
Along with the disadvantages, there are also advantages:
- possibility of installation on an existing pipeline;
- minor heat loss.
It is advisable to install a flexible heating cable on straight pipe sections or with slight bends.
If the pipeline is rarely used, for example, in a country house, the water can be drained from it. Then there is no need to turn on the heating cable.
Connection
The heating part of the cable must be connected to the “cold” part. In addition, it is necessary to reliably protect the conductors at the free end of the heater from moisture with heat-shrinkable tubes. The connection to the power cable is made through lugs. The more reliable the connection, the less often the heating cable will require repairs.
Video about connection
You can learn how to connect a self-regulating heating cable with a termination kit from the video below.
To prevent pipelines from freezing, special heating systems of varying complexity are used. To save money, you can install a heating cable yourself, for example, a telephone cable - P-274. The heating system can be made automatic with a thermostat or manually activated.
In severe winters, it is not difficult to protect the water supply system from freezing; it is enough to use a heating cable that is installed inside or outside the pipes. The heating element prevents the formation and accumulation of ice ridges, leading to unpleasant consequences, which in any case will need to be eliminated - either repairing the damage or replacing pipes broken by ice.
What is a heating cable?
The basic operating principle of a heating cable is the conversion of electrical energy into thermal energy. The main feature of these heating systems is that they only accept energy and convert it into heat without the use of fuel or oxidizer. Systems for heating pipes are heated by the influence of electric current passing through them and do not allow defrosting of external communications. Therefore, it is simply necessary to buy a heating cable for the water supply system in order to prevent failures in the operation of the entire water supply network in the winter. The heating system for external pipelines involves the use of a wire with a sealed, seamless, impact-resistant sheath that easily withstands temperature changes. There is a heating element inside the outer layer. When the temperature drops, the heating cable is connected to the mains. The heating element is activated and heats the entire system. And when the ambient temperature rises, the power to the cable is turned off, and the pipeline operates as usual.
Why is it necessary to use cable heaters?
There are several positive aspects when using heating cables, here are the main ones:
- Saving. Connecting a heating cable allows you to adjust the heating power depending on the external ambient temperature. Plus, nutritional needs are regulated.
- Easy to use.
- Design versatility: a cable heater can be equipped with any pipeline located both outside and underground.
- Safety of use: the insulation system is impeccable, it serves as reliable protection against external thermal, mechanical and chemical influences.
Types of heating cable
The main element of the cable system is the heating cable, which comes in two varieties:
- Resistive is a low-cost heating cable that is easy to install and is most often used in everyday life to equip underfloor heating systems and heat small-diameter pipes up to 40 mm.
- Self-regulating wire is used for heating containers and pipes with a diameter of 40 mm, as well as roofs, gutters, electrical panels, etc.
Resistive heating cable
The operating principle of this element is based on laying a special cable and sensors along the entire length of the pipeline that respond to changes in ambient temperature. They periodically turn off and turn on the heating system when a certain temperature is reached.
You can lay the heating cable with your own hands in different ways: parallel (ribbon) and spiral. The cable is attached to the pipes using aluminum tape. The main thing when installing a heating system is to avoid putting too much tension on the heating cable. Sometimes, for better contact and even heat distribution, it is recommended to wrap pipes and wires with several layers of aluminum foil. Also, to ensure more efficient operation, the system should be equipped with reliable thermal insulation, because if necessary, you will have to repair the heating cable yourself. The insulator is able to reduce electrical energy costs and reduce heat loss. Mineral wool, which has a fairly low thermal conductivity coefficient, can be used as a thermal insulation material.
Self-regulating heating cable
Now let's look at what another type of heating system is. Self-regulating heating cable - these are two insulated conductors located in a polymer that changes its resistance under the influence of temperature changes. No sensors or electronic temperature controllers are needed. That is, as the ambient temperature decreases, the resistance of the polymer decreases and the current increases, which leads to more heat produced. As the temperature rises, the reverse process occurs.
This amount of heat depends on the reaction of the polymer to changes in the temperature of the surrounding atmosphere at a particular or specific point on the wire, and therefore it varies. Thanks to this feature, the self-regulating heating cable is effective in use in various places and has a fairly long service life.
Reliable insulation ensures high safety of the heating cable and its cost-effectiveness. If necessary, it can be cut into pieces of the desired size, which does not affect its properties at all.
Advantages of self-regulating cables over resistive cables
- It is important that the medium be uniform along its entire length, which is very difficult to do in practice. This often leads to overheating of the cable and failure of the heating system. Where the heating cable has been installed, the temperature automatically decreases in places with less heat removal, while in other areas it remains unchanged.
- A self-regulating cable is more resistant to voltage surges and does not burn out if the voltage rises for a long enough time.
- Resistive cables have a fixed length that cannot be changed, while self-regulating cables can be cut into pieces of the required size.
Installation of a self-regulating heating cable. Interior work
A self-regulating heating system can be installed in two ways: inside and outside. High-quality installation of heating cables ensures uninterrupted and trouble-free operation of the water supply, sewer or any other system.
Internal installation is used for pipes of small diameter - up to 50 mm in the absence of direct access to the pipe itself. When the pipeline system is underground, the heating cable is pushed into the pipe with your own hands. Its length should be equal to the length of the water pipe. This method is mainly used when installing new pipes.
Heating cable: do-it-yourself external installation
When installing such heating externally, the cable is fixed to the surface of the pipe. Moreover, its length can be equal to the length of the pipe, or even exceed it. This depends on the installation method, that is, on the method by which the heating cable, which was installed with your own hands, is attached to the pipes:
- Linear method. The length of the cable is equal to the size of the pipe. The number of threads of the heating element is selected depending on the required power.
- Spiral method. The cable length exceeds the pipe length. It is laid around the canal in a spiral. This is the most expensive method of attaching insulating devices.
External installation of heating cables is the simplest and fastest way to set up a system for heating pipes. Sometimes it is more effective than external one. Often, a cable laid inside a pipe defrosts ice much faster than one wound outside. But it performs its functions in any case.
Connecting the heating cable
First you need to connect power from the electrical panel or outlet to the heating cable. When installation is carried out on pipes in a place sufficiently distant from the electrical panel, it is necessary to use the heating cable connection to the electrical network. It is not difficult to do it yourself. It is advisable to use the instructions that come with the product. The connection itself can be made either using a simple terminal connection or using ready-made heating cable solutions.
How to make a heating cable with your own hands?
You can purchase heating elements in specialized or construction stores, but you should be aware that their cost is quite high. With some dexterity and certain technical skills, you can try to make a heating cable with your own hands. To do this, it is enough to use suitable material. A replacement for a branded heating one can be a power one. It is similar to a heating one in shape and characteristics. This cable is thin, durable and rigid. It has reliable insulation and can be used in damp environments.
It is clear that a heating system made from telephone cable will be deprived of many important functions. For example, it will be impossible to carry out the process of self-regulation. In addition, the system does not have special food insulation. However, all the useful qualities described above are not particularly needed, so you can safely use a homemade heating cable. Do-it-yourself installation is not at all difficult. First, determine the location of its installation - that is, outside the pipe. Attach the wire to the surface very tightly. The pipe with the cable is usually tightly wrapped in foil, over which aluminum tape is wound, which is what presses the heating element to the base. Such heating for pipes can be arranged not only for water supply, but also for sewerage. It is necessary to ensure maximum protection of all heating cables and protect them from moisture. To do this, you can use heat and waterproofing. For one-time or periodic work, a heating cable made with your own hands from a power cable can be used in a country house or in a place where people do not live permanently.
In conclusion, we can say that the heating system for heating the water supply, which is the heating cable, is its necessary component for full functioning throughout the year, and especially in winter.
One of the difficult tasks is the uninterrupted water supply of residential buildings and other facilities, especially in winter. To prevent pipes from freezing, they must be laid below a certain freezing level. However, there is no absolute guarantee that the water supply will not freeze and the water supply will not stop.
This is due to the following reasons:
- Abnormal frosts, which are no longer uncommon lately.
- The place where pipes are brought to the house most often freezes.
- Occurrence of accidents on the pipeline route.
Conventional pipe insulation does not give the desired effect during prolonged and severe frosts. The solution to this issue is to use a heating cable to warm the water supply. With its help, you can maintain the required temperature and prevent the formation of condensation on the pipes. In this case, the pipes will still have to be laid in the ground, but to a much shallower depth. At the entrance to the house, you can install a more powerful heating cable and apply high-quality insulation.
The heating cable comes with instructions, after studying which you can easily install and connect it yourself. Heating cables are used not only for plumbing, but also in other areas.
Types and design features
Heating cable is classified into two types:
- Resistive.
- Self-regulating.
Resistive heating cable
This model is the most affordable for the buyer, since its production does not require the use of complex technologies and expensive materials. The power and cable length are kept constant. It is not allowed to cut a resistive cable into several parts, as the resistance will decrease and the core temperature will increase above the permissible value. This may cause the circuit to break.
The resistive cable heats up evenly along its entire length. When creating a project, it is necessary to accurately determine the cable length.
The heating cable can be connected in various ways. The easiest way is to connect it to an electrical outlet. With more complex options, various sensors and electronic equipment with a power regulator are used in the circuits to maintain a certain temperature.
Resistive cable is in turn divided into several types:
- Single-core . This is a simple design with an outer heat-resistant shell, under which there is a copper shielding braided with fluoroplastic insulation. Inside this insulation is a heating conductor. Such a cable is laid taking into account the possibility of connecting both ends on one terminal block. To do this, it is necessary to calculate the cable length to obtain the required temperature. You can do this simple connection yourself.
- Two-core The cable is laid over its entire length. Then one end of the cable with two cores is connected to the power supply, and the other end is closed with a special sealed coupling. This cable greatly simplifies the installation process.
- Zone cable is also a resistive heating cable model. Its design is similar to a two-core cable with the addition of heating coils between the two main cores at equal lengths with equal power. This allows sections of the cable to be cut at a specific pitch. A malfunction in the form of burnout of spiral conductors in some areas leads to the appearance of a cold zone in the faulty area.
Features of installing a resistive cable
- Carefully calculate the required power and heat costs. When calculating, it is necessary to take into account the material of the heated surface and its area, temperature, and humidity. If heat removal is insufficient, the service life of the heating system will be significantly reduced.
- Cables that are used for heated floors in an apartment cannot be used to heat water pipes, since their insulation is not protected from moisture.
- When laying the heating cable, do not allow it to cross.
The main advantages of a resistive heating cable are:
- Increased reliability.
- Stability of characteristics throughout the entire service life.
- Low current when turned on.
- Easy installation.
- Simple device.
- Low cost.
Self-regulating cable
This type of cable works differently. The device of the self-regulating heating element is made in the form of a matrix located between the current-carrying conductors. This matrix is made of elastic semiconductor material. The resistance value of the matrix semiconductor depends on the temperature of the environment surrounding the cable. This changes the power consumption and heating efficiency.
The principle of self-regulation is that the necessary heat is released only in a certain area where it is needed. As the temperature decreases, the cable resistance increases and more heat is generated. Conversely, if the temperature rises, the cable resistance and the amount of heat decreases. With this effect, the cable will not overheat, even if there is an overlap during its installation. Electricity during operation of a self-regulating cable is consumed optimally.
Self-regulating heating is effective for underground pipes and anti-icing systems. During installation, the cable can be cut into pieces of any length, without the help of specialists, and without compromising its working properties. It is not necessary to heat the entire pipeline. It is enough to lay the heating cable only in places with a higher probability of freezing.
Self-regulating cable is expensive, but is very popular. Purchase and installation costs are quickly recouped during operation due to electrical energy savings.
Advantages
- Elasticity and flexibility make it possible to lay the heating cable for any pipe network, in structures of different geometric shapes.
- The operation and installation process does not harm the environment.
- Possibility of self-installation of the system, subject to proper calculation and fulfillment of all heating installation requirements.
- Simple work that does not require professional skills.
Application
The versatility and ease of use, as well as the operating principle of the heating cable, determine its wide application:
- Heating of garden paths, steps and sidewalks. This eliminates injuries and falls of pedestrians on a frozen surface.
- In industrial buildings and residential premises, a heating cable is used to maintain the required water supply temperature, as well as heating pipelines located in the ground and in the open.
- Heating the floor covering provides comfort and warmth in the room on frosty days.
- Heating of pipes located on the roofs of houses, drainage systems, roofing coverings. The wire is fixed inside or outside the pipe. When the heating system is working, destruction of the pipeline, falling ice and icing of the roof edge are eliminated. This ensures safety for people.
Installation methods
The heating cable for heating the water supply system is laid inside or outside the pipe. Each method involves the use of a different type of cable.
Installation inside a pipe
Requirements for indoor installation of heating cable:
- Sealed end coupling.
- no less than IP
- No harmful substances when heated.
To install the wire inside the pipe, a tee is installed at its end. The wire is inserted into one of the branches of the tee with a gland seal.
The coupling located at the transition between the electrical supply cable and the heating cable must be located behind the gland and pipe, since it is not protected from moisture.
The mounting tee can be designed with different angles. With this method, the cable is not secured, but tucked inside.
External installation
The heating cable for the water pipe is fixed from the outside tightly, using the entire surface of the cable. Before installation on metal pipes, it is necessary to clean them from rust, dirt and dust, as well as traces of welding. The surface of the pipes should not have elements that could damage the heating wire.
The heating cable is laid on a clean surface, secured after 30 cm with adhesive metallized tape or special clamps. When laying two cables, they are installed in the lower cold part of the pipe parallel to each other, without touching. If more than three cable threads are laid, then most of them are placed below, also without touching.
Another installation method is spiral installation. Be careful when doing this, as repeated and sharp bends can damage the cable. You can gradually unwind the coupling by winding the freed cable around the pipe. You can also fix the cable with slack, which is wound and fixed with adhesive tape.
To heat a plastic pipe, metallized tape is first glued, which increases heat conductivity and heating efficiency. A feature of the installation is the following factor: valves, tees and other plumbing devices require more heat. Therefore, when installing on each such device, it is necessary to make several loops without bending the heating cable too much.
For this, special types of insulation are used: polystyrene foam, made in the form of pipe elements, and called shell. It has good insulating properties and does not absorb moisture.