Where winters are cold, water pipes can freeze. Therefore, it is necessary to install a self-regulating heating cable to heat the pipes. If this is not done, the water inside may freeze and burst the pipes.

The heating cable can be installed both inside and outside the pipes.

Heating element structure

Pipe heating systems are not new. In the old days, industrial communications were actively heated with such devices. Recently, a self-regulating heating cable for water supply is often installed in private and communal households. This is explained by the fact that sometimes it is technically impossible to lay water pipes deeper than the freezing point.

Structurally, the self-regulating heating element consists of the following parts:

1. 2 conductive copper wires.
2. Polymer matrix combining 2 cores.
3. Double layer seamless insulation.
4. Heat reflective copper screen.
5. External insulating coating.

As the diagrams show, the basic heating element is a polymer matrix, inside of which there are 2 conductive wires. It heats up constantly. If desired, the contents of the self-regulating cable are cut into 20 cm segments.

The matrix has a main feature: under the influence of external temperatures, such a pipe heating system spontaneously changes the volume of heat released.

This effect manifests itself differently in different sectors. Thus, underground sections of the pipeline may remain cold, while sectors remaining outside heat up. If the temperature drops, the resistive pipe heating cable, when connected to the AC mains, starts heating. It is recommended to turn on the pipe heating when the air temperature drops to +5ºС, since in such cases there is a high probability of night frosts.

The pipe heating system is extremely easy to use. If it is installed correctly and correctly, then its service life becomes unlimited. The level of safety increases significantly if there is good protection against overheating.

How to choose a device

When you have to buy a self-regulating heating cable, it is advisable to clearly define the required technical characteristics in advance. It is necessary to calculate the cable power. In private buildings, a self-regulating cable is used, the power of which starts from 5 W/m.

The parameters depend on the specific option:

• if the pipeline heating system is located below ground level (buried into the ground), and the heating units and elements are mounted inside the pipe, then a power of 5 W/m is sufficient;
• when underground water supply networks are heated from the outside, a heater with a power of at least 10 W/m is used;
• for open water pipes, the use of a device is required, the power of which should not be less than 20 W/m.

It makes no sense to use a self-regulating heating cable with a power exceeding 50 W/m, since most of the generated energy will go into the air. A heating cable should be used for water supply with a low operating temperature (within 65ºC).

Heating cables are available for food and technical purposes. Household water supply can only be equipped with a food version. But for external installation, any self-regulating cable will do.

Internal installation

There are often cases when the installation of heating equipment is carried out on a laid and working water supply system, the thermal insulation of which is resistant to low temperatures. Then a wire containing a fluorine-containing polymer is pulled inside the pipe. If a food water supply system is being installed, then the element that provides heating for the pipes must certainly have a certificate of approval for its use in the food industry.

If the thread is wound from the top, then it does not need additional clamps. But when supplying the heater from below, the thread will have to be secured with special reliability so that it does not move down.

The self-regulating cable for heating pipes is installed as follows:

1. It is necessary to measure the sector of the pipeline that is to be additionally heated.
2. One end of the tape opens and a coupling is installed there. Sealing seals are added to it.
3. The opposite end of the wire should be insulated. The edge sinks into the pipe. The procedure must be done as carefully as possible to protect the insulation.
4. The cable with coupling is connected to the electrical network through a plug/distribution box. An inscription is applied to the treated sector of the pipe with the heating cable using a bright marker.

External cable installation

Laying a cable for heating pipes along their surface is very simple. For fixation, aluminum tape or special adhesive tape is used. The following schemes are known:

1. Single row. The cable thread runs in a straight line along the pipe.
2. Multi-row. Several parallel rows are laid.
3. Wavy. When calculating, the length coefficient (1.6-1.7) is used.
4. Spiral. The pipe is wrapped around the cable. In this case, 1 m of water pipe will require 2 m of cable.
5. Mixed option. It is a combination of several cable fastening methods. The scheme is acceptable where the pipe is equipped with distribution units or shut-off valves.

Instead of a conclusion

A do-it-yourself heating cable is an excellent solution to the problem of ensuring reliable thermal insulation of pipes in hard-to-reach places. The heating cable for water supply is very easy to install and is used when sewerage and drainage systems need additional protection.

To save pipes from freezing, they must be heated. A very simple and relatively cheap method is used for this. A heating cable is laid along them. This method can be used to heat:

• Sewer pipes.
• Plumbing with technical and drinking water.

There are many types you can find on the market. However, self-regulating has the most optimal properties. It does not require installation of an additional thermostat for its operation. It warms up even particularly cold sections of pipe well. Since connecting the heating cable is not difficult, you don’t have to call a specialist, but do all the work yourself.

Before you start installing CSR, you need to take into account all the work that

carried out with pipelines:

• Electrical supply.
• Instrumental works.

Before starting installation, it is necessary to complete the installation of all tools and conduct a high pressure test of the pipeline.

Where is the cable located?

It can be mounted in several ways:

• Along the surface of the pipe.
• Spiral.

The latter option is chosen only when it is difficult to find a specific type.

Linear installation

When laying along the pipe, it should be in its lower section. Thus, mechanical damage is excluded.

Spiral installation

When you have to create a spiral installation, the consumption also increases significantly. The calculation is carried out according to a certain formula:

Amount of cable required = total pipe length x helix factor.

The spiral pitch is determined from a table that takes into account the diameter of the pipe.

Types of fixation

KSO is usually fixed to the pipe in several ways:

• Fiberglass tape, with adhesive surface.
• Aluminum strip.

In addition, it is possible to install plastic clamps. But certain conditions must be met. The permissible heating temperature of the clamp must be higher than the heating temperature of the cable and pipeline. It is necessary to maintain a distance of about 300 mm and secure tightly.

To avoid damage, do not fasten:

• Steel strip.
• Wire.
• Vinyl tape.
• Scotch tape.

Aluminum adhesive tape is used only if so specified in the project. In most cases, it is installed on plastic pipes to overcome the thermal insulation effect emanating from the plastic.

Heating cable connection diagram

Connecting CSR is quite simple. It is necessary to apply a voltage of 220 volts to the conductors of the cable. The heating end must be well insulated so that the current-carrying wires do not come into contact.

If there is a grounding, it must have a special braid.

The connection method depends on several factors:

• Where will it be installed?
• Available tools.
• Availability of consumables.

The connection diagram for any method is the same. If there is no braid, voltage is simply applied to its cores.

The opposite end must be insulated.

Current-carrying conductors must be reliably protected from contact with each other.

If the heating cord is equipped with a ground shield, it must be grounded. If grounding is impossible, the screen is simply cut off.

More details about the connection can be found on the website: http://zona-tepla.ru/podklyuchenie-greyushhego-kabelya/

Connecting to the network is an alternative method

We took this cable:

The heating conductor (3) and the conductors (1 and 2), through which current flows, cannot be short-circuited

1. This is what the end looks like.
2. Cleaned it up.
3. Using this terminal block I connected it to the wire.

The opposite side must be insulated. It is prohibited to bridge the conductors. And we must ensure that they do not bridge in any environment. You can buy a special plug for this. They cost around 300 rubles apiece. But you can do everything yourself using improvised means, such as heat-shrink tubing and a heat gun.

1. Thermal gun.
2. Heat shrink tube.
3. End of insulated cable.

The plug is made as follows. We put on the heat shrink tube. We warm it up with a hairdryer. Afterwards we fill the entire structure with a heat gun.

The same procedure can be done with the terminal block to which the cable power is connected. You can also wrap everything with electrical tape just in case. If operating conditions are harsh.

In which zone is it installed?

Any icing area must be equipped with a heating cable. Gutter gutters require a power of at least 300 W per square meter.

To heat drainpipes, install 2 pieces at the same time with a power of 20 W per square meter. meter.

Heating the valley roof will provide power in the range of 250-300 W per square meter. Installation is carried out at the top and bottom.

The roof eaves, made in the form of a “snake,” are heated by a cable laid along the very edge.

Table 1 (for metal pipelines).

Table 2 (for plastic pipelines).

Important:

• A cross marks areas where it is not recommended to wind the cable, as it can be damaged.
• The pipeline must be thermally insulated.
• The tables indicate the length that must be laid per 1 m of pipe. In cases where winding is required, the laying step in meters is given in parentheses.
• For those pipe diameters where flow rates are not indicated, it is necessary to use thermal insulation of greater thickness.
• The calculation of the lengths of the heating (heating) cable is valid for thermal insulation with a thermal conductivity of no more than 0.05 W/(m*K).

Be careful when laying. This will make it possible to avoid some problems.

Do not twist the wires together. A short circuit will occur.

The black polymer surrounding the current-carrying conductors must be insulated. It conducts current, so it is considered a conductor and must be treated as such.

The electrical connections of the entire system must be well insulated to prevent sparking and also to prevent fire.

Any electrical connection for the heating cable must be properly protected from moisture.

Do not use it if its heating temperature reaches the maximum value. This leads to a decrease in its service life.

If the cord is damaged, it must be replaced with a new one. Even stopping the operation of any element will make the entire system inactive.

For explosive environments, it is necessary to install only a specialized cable with special components. Similar conditions include some industries:

• Chemical.
• Petrochemical.
• Coal.

Special cables are installed for them, approved for use in this area.

If inappropriate equipment is installed, an explosion or severe fire may occur.

A heating cable for water supply and its use to protect pipes from freezing is a guarantee of reliable protection and long-term operation of water pipes even in harsh climatic conditions. Everything can be done with your own hands. The plumbing is one of the most basic communication systems in the home, so it is extremely important to secure the pipes in a timely manner and protect them from icing. Otherwise, freezing of pipes can lead to interruptions in water supply and even ruptures.

Heating cable for water supply

To prevent this from happening, electrical heating is installed inside or on top of the pipes, which provides a heating cable for the water supply. An easy-to-install water heating system can prevent many problems.

Even further south, where there are only short-term sharp drops in air temperature, measures to protect the water supply from freezing will also not be superfluous. To fully enjoy the coming of winter, you need to take care of the comfort and serviceability of all heating systems before the onset of cold weather.

Heating cable for pipes: operating principle and advantages

Heat is generated thanks to electricity passing through the cable, which prevents the pipe from freezing during frost. When choosing a wire, it is a good idea to pay attention to its thermal conductivity coefficient (W/m), which indicates the power of the electrical cable and the unit of its length.

You can install this heating element yourself. If you decide to purchase a ready-made cable, you should take into account that a single-core wire does not have protection against electromagnetic radiation, while its two- and three-core counterparts have it, as well as protection for the current-carrying core.

The heating cable consists of:

1. inner core (made of high resistance material);
2. shielding braid (aluminum or copper);
3. insulating material;
4. general protective shell.

Internal structure of single-core and two-core electrical cables

Installing this heating element has many advantages:

• With proper calculations, the water in the pipes will not freeze even at significant sub-zero temperatures.
• Internal and external installation of the cable on the pipe is allowed in any location of the system: underground, outdoors, indoors.
• Protection against burnout and the possibility of installation for drinking water systems (there are special heating electric cables made from environmentally friendly materials).
• Easy installation and comfortable operation.
• Possibility of adjusting power depending on changes in air temperature.

There are two types of heating cables - self-regulating and resistive.

Resistive heating cable

It can be placed inside the pipe or outside along the entire length of the water pipe. Thermal sensors installed on the pipes monitor the temperature: when the set limit is reached, they start heating the system, and after a decrease they automatically turn off.

For more efficient operation of the heating cable, it is recommended to use additional insulation. This can be mineral wool or foam rubber (Merylon).

The principle of laying this cable depends on the desired power: spiral, waves, in one or several rows. It must be laid without active tension, and to enhance the heating effect, you can subsequently wrap the pipe with aluminum foil.

Self-regulating heating cable for water supply

A self-regulating cable has a semiconducting matrix that changes its resistance depending on temperature changes in the environment. The colder the pipes, the greater the heat generation.

Initially, the self-regulating heating cable is fixed “in place”, and after installation it is connected. You can cut the cable in any required place without fear of the appearance of cold zones. The wire can be of any length.

Heating cable for water supply outside or inside the pipe - installation features

A heating or heating cable inside the pipe is installed if the water supply system is already in use and freezes when severe cold occurs. This cable is installed inside the pipe through a gland.

An important nuance is that if the heating cable is installed outside the pipe from above, then additional fixation is not required. If the heating element is installed from below, it must be securely fixed to prevent it from slipping.

If you plan to heat a pipe through which drinking water passes, then the sheath of such a wire must be made of a polymer that meets all food safety parameters.

Installation of a self-regulating cable inside the pipe from above

To install the cable inside, accurate measurements of the length of the section of water supply that needs heating are required. The heating cable must be inserted into the pipe very carefully to avoid damage to the protective sheath. Cables are not routed through shut-off valves.

The cable is secured over the pipe using aluminum adhesive tape (regular tape cannot be used). During the installation of the heating cable, it is necessary to ensure that the wire is not pinched, stretched, or chafed by sharp elements. First, the electrical cable is attached to the pipe with separate pieces of aluminum tape, and then more radically, along the entire length.

Installing a heating cable over a pipe

If the pipe is plastic, then before installing the cable it would be useful to cover it with aluminum tape or foil. The thermostat sensor, coupling, heating section and other additional elements are also attached using aluminum tape.

DIY heating cable for water supply

If you have basic technical skills, you can try making a homemade analogue of a heating cable.

An alternative to the electrical cables described above can be the power telephone wire P-274M (“vole”). This cable has high rigidity and reliable insulation; it can be used for internal and external installation on pipes. It is not suitable for drinking water pipes (no food insulation), and it does not have the ability to self-regulate.

Such a system is optimally suited for cyclical heating of pipes, for example, in a country house where the owners come periodically and do not live permanently.

To expose the “vole” veins, they are initially separated, and then the resulting single cable is folded in half and twisted again. To ensure a sealed entry of the electrical cable, a flange from a flexible hose for water supply is ideal. Special attention should be paid to sealing the input: after inserting the cable into the fitting, it is best to fill it (the input) with epoxy resin and secure the connection with a nut.

If you are installing a heating electric cable outside the pipe, then you should not unravel it, but should connect it to the back side of the heated area. All connections must be carefully insulated.

External view of a water pipe with a heating electric cable

In general, heating pipes not only protects them from icing, but also extends the service life of the water supply system. The absence of temperature changes and condensate accumulation has a positive effect on the general condition of pipes of any type. The use of heating or heating electric cables guarantees comfortable use of the pipeline even in harsh climates.

Useful video on installing a heating cable:

During periods of severe frost, water may freeze in sewerage and water supply systems, which often leads to a number of unpleasant consequences: from stopping the water supply to bursting pipes.

To avoid such troubles, it is recommended to use a heating cable for the water supply, which can be resistive or self-regulating. Installation of such a wire will help prevent the formation of ice plugs in the pipes, maintain the supply pressure at the technological level, and when laying a new water pipeline, the use of the cable will reduce the depth of its occurrence in the ground.

Resistive heating cable for water supply.

The resistive heating cable system works on the following principle: a cable is laid along the entire length of the pipe (along the surface or inside), temperature sensors installed on the pipe determine the ambient temperature, and the control thermostat is sensitive to any change in relation to the specified parameters. If the temperature drops below, the heating system automatically turns on: current flows, the conductor begins to release heat, warming the pipe and the water in it. When the required temperature level is reached, the system automatically turns off.

The cable consists of a metal core enclosed in insulation. It is heated evenly along its entire length and, if you do not monitor the temperature, it can burn out. In order for such a heating system to operate most efficiently, the pipeline should be provided with very good thermal insulation - this will significantly reduce energy costs and reduce heat loss. For thermal insulation, you can use any materials with a low thermal conductivity coefficient, for example, mineral wool.

Based on power calculations, the heating cable can be laid on the pipe in one or several parallel lines, in a spiral or in waves. Installation is easy, without tension, attached to the surface with aluminum adhesive tape. To strengthen the contact of the cable with the pipe and ensure better heat distribution over the surface, you can wrap the pipe with the cable in several layers of aluminum foil.

Self-regulating heating cable for water supply.

The self-regulating heating cable for water supply was developed as an alternative solution to the resistive system and it was a great success. The cable has excellent performance and technical characteristics; it can be successfully used in various anti-icing systems. Such systems, for example, are installed on the roofs of buildings to prevent the formation of ice icicles.

A self-regulating heating wire is a pair of insulated conductors enclosed in a polymer that is sensitive to the slightest change in temperature and changes its resistance depending on this. The lower the temperature drops, the more the resistance decreases and, accordingly, the current strength and the amount of heat generated increases.

Response to temperature changes occurs at any point along the entire length of the wire, so the amount of heat generated may vary from place to place. This feature allows the material to be used with great efficiency. In addition, it is highly economical and safe to use, since it is equipped with very reliable insulation. The scope of its use is truly limitless, and its service life, with constant use, is at least 40 years. To install the cable, you can cut it into pieces of any length - this will not reduce the efficiency of work.

How to make a heating cable with your own hands.

You can purchase heating cables in a retail chain, but you should be aware that their cost is quite high. But, with some dexterity and some technical skills, you can try to make a heating cable with your own hands, using an alternative material.

Experienced craftsmen claim that the most suitable replacement for a branded heating cable is the so-called “field” - a power telephone cable intended for military field communications, its official marking is P-274M. It is thin, quite durable, rigid, has good and reliable insulation, and can be used in a damp environment.

Naturally, a system made from a homemade heating cable will lack some qualities, for example, it will not have special food insulation and there will be no self-regulation function. If it does not work constantly, but only periodically (for example, it is turned on occasionally at a dacha where they do not live permanently in winter, but only come from time to time) and the cable is laid not inside the pipe, but outside, then it is quite possible to do without the above beneficial qualities.

When installing a “field wire” inside a water pipe, so as not to expose the wire at the end, it is better to unravel it into two wires. Then bend the single wire in half and double it again. At the two open ends, it is necessary to provide a sealed entry for the wire; it can be constructed from a flange from a flexible water connection. The input must be truly sealed and not allow a drop of moisture to pass through; for this, the fitting, with the wires threaded inside, must be filled with epoxy glue and slightly flattened; the union nut will allow the connection to be tightened well.

If the cable is supposed to be laid over a pipe, then there is no need to unravel the “field wire”, but simply connect the wires at the opposite end of the heated area. The connection must be carefully insulated.

The wire must be attached very tightly to the surface. First, the pipe with the cable should be wrapped in foil, and tape should be wound over it, which, in fact, will press the cable to the heated base. Next, wrap it all with insulation, for example, mineral wool.

In this way, heating can be arranged not only for water supply, but also for sewerage. The current flowing through the “field switch” should not exceed 9A.

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Freezing of water pipes is a fairly common problem in private homes and cottages. They can be buried deeper into the ground, or simply insulated, but at the entrance to the house, in severe frosts, they will still freeze. Experts recommend installing a heating cable for the water supply.

Advantages of a heating structure for water supply:

• If installed correctly and calculated correctly, then throughout the cold weather the water supply will be protected from severe frosts.
• The heating wire can also be installed in drinking water pipes.
• The self-regulating cable can be used both inside and outside the water supply system, outdoors and indoors.
• The self-regulating wire can independently control the heating temperature, depending on the ambient temperature.

The advantages make it possible to freely use water supply in areas of the harshest winters.

The heating cable is designed to maintain the required temperature of sewer pipes and water supply systems that are located on the street. Otherwise, the water pipes will burst.

It is recommended to turn on the heating structure when the air temperature drops to +5. If you wait until the reading on the thermometer drops to minus, the water supply will begin to freeze. It will take more time and energy consumption for heating. While the water thaws, passage will be difficult and the pressure will be weak.

Previously, heating cables were used in industrial plants. It is only now that this heating system has begun to be used at home for water supply systems.

Heating cables are divided into two types:

• resistive;
• self-regulating.

But the second version of the heating design has more advantages, and therefore is used more often.

Operating principle of the heating element

A resistive cable has a metabolic conductor that heats up when an electric current passes through it.

But, no matter what the air temperature is, +5 or -10, the heat transfer and energy consumption are the same. For control, a thermostat and temperature sensors are installed in the heating system, as in electric heated floors.

This type of heating cable can be single-core or two-core. A single-core cable is connected to the water supply on both sides. Two-core, on one side, a plug is attached, on the other - a cord with a plug for connecting to a 220 V network.

When laying resistive cable, the wires should not overlap or be too close; when crossing, they will overheat and can quickly fail. And yet, this type of heating cable cannot be cut, otherwise it will simply deteriorate. Therefore, it is settled entirely at any size.

The self-regulating cable heats up the polymer; it is located between two conductors. The more it heats up, the less heat it emits, and when it cools down, the more heat it emits. Thus, it regulates the temperature independently. Due to its properties, this type of heating cable is called self-regulating.

Has the following advantages:

• does not burn out when crossing wires;
• it can be cut anywhere, but you will need to make an end coupling;
• the element can be of any length.

The only drawback of a self-regulating cable is the high price, but if you take into account all the advantages and a service life of more than 10 years, the price is justified.

It is worth considering that pipes with heating cables need to be insulated. Otherwise, to heat the water supply you will need more power and more electricity consumption. Or, in severe frosts without insulation, a flexible heater may not cope with its task.

Methods for installing a heating cable

The heating cable can be installed externally or internally. For each installation method, a certain type of wire is used. Some are intended for indoor or outdoor use only. How the heating element is installed in the water supply is indicated in the technical specifications.

Installing a heating element inside the pipe is recommended if there are no other installation options outside. Usually when the water supply is in inaccessible places.

To install a flexible heater inside, it must meet the following requirements:

• the shell must be free of damage and release of harmful substances;
• degree of electrical protection not lower than IP68;
• Sealed installation of the end coupling.

The transition point to the electrical cord, as well as the coupling, should not be located in the pipe. The wire is not fixed, it is simply tucked inside.

The positive aspects of this method are that with direct contact with water, less electricity is spent on heating the water supply, and it is less problematic to install. It does not require any special fastenings; when repairing, you just need to pull it out of the tee without breaking the ground. There is no need to disclose special structures and insulation materials.

There are disadvantages of the internal method:

• there is less free space in the pipe;
• the element gradually becomes overgrown with plaque, and the passage in the water supply becomes clogged faster.

This installation method can only be used in straight and not very curved water pipes. It is prohibited to pass the heating element through tees or through shut-off valves.

Step by step installation:

1. first, a gland assembly is put on the cable;
2. a tee is placed in the designated place, through which a flexible heater will be introduced;
3. further, it is pushed to the desired place in the water supply, where the water often freezes;
4. After installation, the stuffing box assembly is screwed in and must be sealed.

Outdoor installation

Before installing the heating cable, it is necessary to prepare the pipes. Clean them from dust and dirt, get rid of rust and weld marks. So that there are no irregularities left on the surface. Because it should fit tightly to the walls of the pipes and not be damaged during installation. It is fixed on clean metal every 30 cm, and at least with aluminum adhesive tape or plastic clamps.

If the heater is installed outdoors in the lower part, that is, in the coldest place, then it must be fixed well. To prevent slipping or even the wire may come off. If several wires are installed, then most of them should be at the bottom. And be at a distance from each other if these are resistive models. Under no circumstances should heating wires be interrupted. Another installation method is installation in the form of a spiral. But installation must be carried out very carefully; they do not like sharp or frequent bends.

Installation with a spiral can be carried out in two ways:

1. you need to gradually unwind the coupling and loop it around the water pipe;
2. secure the flexible heater with sagging using aluminum tape;
3. then wrap them around the pipe and secure with a special metallized tape.

If you plan to heat water supply from plastic pipes, then you first need to glue the place where the thread will be attached with aluminum adhesive tape to improve thermal conductivity, and then you can start attaching the heating cable.

More heating material will be spent on tees and various similar devices, because more heat is needed to heat these parts. But it is recommended to ensure that the loops are not too sharply bent when laying.

It is not advisable to use mineral wool for insulation. This material is afraid of moisture and, when wet, loses its thermal insulation properties. After freezing when wet, and then when the temperature rises, the air will disintegrate into small parts. And if the pipeline is located outside, then getting wet is guaranteed.

Insulation materials that will shrink under heavy weights are not suitable, as they will lose their thermal insulation properties. You can use foam rubber as insulation for water pipes, provided that there is no pressure around it. Another option is to put a rigid pipe on top of the polyethylene foam; a plastic sewer model can be used. One of the best options is polystyrene foam insulation, also called shell. It is not afraid of water, can withstand not very heavy loads, and has good characteristics.

Thermostat value

To pay less for heating the water supply, it is better to install a thermostat. In the event that a self-regulating wire is installed. It turns on at +3 and stops working at a temperature of +13.

But if the water is from a well, the temperature in it will not be higher than +13, so it turns out that the cable will work all year round, that is, constantly. Although in the summer you can disconnect it from the network, but what to do in the autumn and spring, when the air temperature can suddenly drop below 0 degrees.

There is no need to heat the water that goes into the shower; it will be heated using a boiler.

Conclusion - it is better to install a thermostat; it has a shutdown function above +5 degrees. There will be significant energy savings, and the service life of the heating cable will increase several times.