Laying a heating cable in a sewer pipe. Heating of sewer pipes with a heating cable. Sewer insulation from the inside

The principle by which heating works lies in the operation of the core wire, which is actually the basis. The heat generated by the passage of electricity is transferred to the surface of the pipes. Heating is carried out not only on the surface, but also from the inside, not allowing condensate to accumulate.

The outer sheath of the cable and its protection against external factors is the outer insulation. Inside it are two cores. Conductive wire (cold), heating wire (hot). The elements are connected by the most precise laser soldering, and there is a plug at the end of the cold wire.

All heating cables used to maintain the temperature inside and outside, sewer pipe laid at the required depth, are divided into two types:

• self-regulating;
• resistive.

Self-regulating cables

The complex design of the cable puts it one line higher in terms of cost. Changes in temperature and heating of pipelines are regulated by sensors installed in it. The release of heat increases when the indicators decrease below the specified norm, and decreases or turns off altogether, when the indicators are normalized.

On a note. This principle of self-regulation of the cable that heats the pipes allows you to maintain optimal mode and exclude the possibility of overheating, and as a result, failure.

The main feature is the possibility of uneven heating. In one area, the temperature may be different relative to the degree of cooling of the sewer pipe from the outside and inside.

Resistive control system

Cables belonging to this category operate with a constant current resistance. This means that once the heating is turned on, the temperature will be maintained continuously.

You can reduce energy consumption and eliminate the possibility of cable burnout by installing additional sensors. They regulate the switching on and off of the system upon reaching certain temperature set in advance. The disadvantage of the thermal relay is that it significantly reduces the service life of the cable heating the sewer pipes.

For uninterrupted operation and an increase in the period after which it will be necessary to repair the sewerage in the apartment and outside, not all pipes need to be heated, but only the following sections:

• connection points of the septic tank, with filtration wells;
• cleaning filter outlets;
• connection points to treatment plants and septic tanks.

Given the characteristics of the systems presented above, self-regulating cables are more often used. Heating pipes with such a system is faster. And so that no force majeure situations happen during the heating process, some requirements must be observed:

• during installation, it is forbidden to lay the cable on sharp objects, stones or metal bars found in the ground;
• the permissible bending radius must not be exceeded;
• do not connect coiled cable to the network;
• after laying the system, the cable must be covered with heat-insulating material.

Laying is done in two ways. The first is along the pipe. One or more parallel threads are mounted, depending on the power consumption and output of energy. The second is around the pipes. The cable is wound in a spiral.

Proper connection is the key to trouble-free operation

There are several nuances of fastening regarding the material of sewer pipes. If the system is laid out plastic material, before laying the cable, the line is wrapped with foil films. Fixation directly on the pipe is carried out aluminum foil. It is not necessary to omit the process of insulating sewer pipes. This is also additional protection cable.

Loops of wires are attached at flange connections in such a way that they can be disconnected at any time. That is, no capital fixations. Keep your distance when laying. Resistive cables should not intersect in turns and must be treated with hydro before laying the line. insulating materials. Thermal sensors are installed on the pipe according to the type of fixation of the heating element itself.

By adhering to these rules, pipe heating will be on high level and they will not freeze even in the most severe frost.

There is an option to install a heating cable inside the sewer lines. Using such a scheme, tees are pre-installed through which it will be introduced. This option is effective for eliminating ice jams, but there are certain risks:

• installation of a tee affects the reliability of the pipeline;
• the cable located inside can be an obstacle in the way of garbage dumping;
• it is difficult to install the system if the highway is laid with large quantity bends.

On sale, the heating cable is offered in ready-made kits of a certain length or footage. The second option is more profitable because you can purchase as many as you need to protect all lines when installing sewer pipes.

On a note. Maximum length cable for heating pipes should not exceed 100 meters in outdoor use and 60 m in indoor.

Systems manufactured for domestic use are characterized by power from 9 to 24 watts per meter of product. For installation on outside need more powerful equipment. For the location of the heating inside, a less powerful system is suitable.

Carefully inspect the cable when purchasing it in a store. Even minimal damage will be the result of the electrification of the pipe. Be guided by the recommendations in the accompanying documents and do not hesitate to ask for advice from experts.

If you do everything right, then for 20 years you can forget that the sewer pipe can freeze. Heating in automatic mode will maintain the required parameters.

In order to install a heating cable for sewage inside a pipe, you must perform the following steps:

1. Put a heat shrink tube on the cable (insulation function).
2. Clean the cable from the presence of insulation and braids.
3. Treat the wire by separating the heating cable and stripping.
4. String heat shrink tubing on each wire.
5. Heat up the heat shrink tubing with building hair dryer until the wires are completely clamped.
6. Leave the ends of the wire and strip them.
7. Clamp the pre-placed metal tube braid.
8. Leave the ground wire, which is 80 mm long, cut the rest and clean the ends.
9. Connect the supply and heating wires by clamping the heat-shrinkable tube with a building hair dryer.
10. Use electrical tape for connecting cables.
11. Clamp with heat shrink tubing the place where the heating cable connects with a building hair dryer.
12. Remove the rest of the metal braid.
13. Put a heat shrink cap on the end of the heating cable and press it against the other cables.

Rating of the most popular heating cable manufacturers

1. Ensto (resistance to influence chemical elements, resistive, use synthetic rubber insulation).
2. Lavita (self-adjusting, synthetic insulation).
3. Devi (resistive, two-core, laid in pipelines, as well as in concrete floors, provide floor heating, high working power).
4. Raychem (self-regulating, heated water pipes small diameters).

The situation with the freezing of the sewer pipe is quite rare, because. such a pipe has a slope from the consumer device, therefore, unlike a water pipe, it is empty most of the time, and portions of liquids periodically flowing through it are usually ... warm. However, if small water leaks occur, due to a malfunction of the descent assembly in the toilet bowl or due to a leaking faucet, then the water does not have time to fast walk to a warm septic tank and it freezes along the way.

Such smudges freeze layer by layer and eventually completely block the diameter of the sewer pipe.

In order to eliminate the ice plug, you need to melt it with boiling water and salt, or dig out the pipe and try to warm it up with blowtorch or building hair dryer.
After removing the ice block, it is necessary to check the pipeline for cracks, and if necessary, replace the damaged section.

Sewer cable heating

In its turn heating a sewer pipe with a heating cable prevents such problems and increases the life of the sewer system in your home.

The power of the heating cable is selected in such a way as to compensate for the heat loss of the pipe by 120-160% at minimum temperature according to MSN 2.04-01-98 "Construction climatology":

Considering that in most cases household sewerage pipes with an internal diameter of 5 0 before 110 mm and thermal insulation with a thickness of 20-50 mm (PPS, PPU, PPE), to solve the problem of protecting sewer pipes from freezing, you can use self-regulating heating cables of low-temperature class with linear power from 16 W/m to 32 W/m.

We list the most popular:

Self-regulating cables for heating sewer pipes

• 

• Samreg is sold by the cut, a multiple of meters. Due to the design features, it saves energy and prevents overheating of the pipe.
  Resistive cable used in underfloor heating for heating pipes inside is not suitable, because. it is supplied in ready-made kits (from 20 m), the length of which cannot be changed and is not protected from local overheating (which is fraught with failure).

  Installation of cable heating sewerage

  At the first stage, it is necessary to determine the length of the heating cable, taking into account cold bridges (flanges, supports, valves, etc.) and power cable. Then install the end and coupling using a hair dryer.

  
  
  

  In case of installation on the pipe the heating cable is fixed along it along its entire length. If the pipe is metal, then fiberglass tape is used for fasteners. Transverse fastenings are carried out every 30-40 cm. If the pipe is plastic, then to ensure thermal contact, the cable is glued along the entire length with aluminum self-adhesive tape and additionally across every 30-40 cm.

  If it is not possible to install on the surface of the pipe, then it is allowed installation of the heating cable inside the pipe.
  In this case, the external insulation must be resistant to aggressive environments.

When laying the outer pipes of the sewerage system, it is recommended to deepen them below the freezing level of the soil, but this is not always possible. Here, the characteristics of the soil, and technical features the system itself. If it is impossible to go deeper below the freezing level and there is a high probability of pipe freezing, it is necessary to provide sewer insulation. To do this, you can use various thermal insulation materials or heating cable. It's about last version and there will be talk.

Types of heating cable

Electric heating cable has a certain resistance. When current passes, it heats up and heats the space around it. Heating cables differ in the place of their installation. Such devices can be placed both outside the pipe and inside it. Many experts recommend using the first method.

Note! Mounting the heating cable from the inside should only be used in extreme cases.

Electric heating cables themselves are available in several types. Namely:

• Self-regulating. Such devices are considered the most modern. A self-regulating cable is able to change its resistance (and hence the degree of heating) depending on the temperature environment. And on separate sections at the same time there can be different resistance. This feature makes it possible to significantly save on electricity;
• Resistive. The cheapest type of heating cable. It heats up along its entire length with the same degree. To prevent the device from burning out from overheating, it is necessary to install thermal sensors;
• Zonal is an analogue of a resistive heating cable. Their difference is that the zonal one heats up only in certain areas, this makes it possible to cut it into the necessary pieces and insulate certain parts of the sewer system. The zonal cable, like the previous one, needs to install a temperature sensor.

Also, cables are divided according to their power. As a rule, for sewerage systems use products with a power of 33 W per running meter.

Warming outside

To equip sewer pipes with a heating cable in an external way, it is necessary to prepare adhesive tape. It is with its help that you can attach the cable to the surface. Most of these devices have a polymer protective shell, so metal fasteners cannot be used.

Note! If the pipe is made of polymers, then before installation work it should be prepared. All outer surface should be wrapped in foil. Such an aluminum layer will allow the entire pipe to heat up evenly.

The very progress of the installation of an electric heating cable is as follows:

• The cable is laid out along the pipe, and several parallel threads can be used. Such styling is considered the most desirable. If the length of the cable allows, then (if necessary) you can wind it around the pipe in the form of a spiral.
• Fixation is carried out using adhesive aluminum or other heat-resistant tape. In this case, it is necessary to achieve a tight fit of the cable to the pipe.
• At the junctions of the pipes, the cable is laid in a loop (1.5 meters) so that later it can be disconnected without dismantling the heating.
• Thermal sensors are attached to the pipe parallel to the cable (if non-self-regulating devices are used).
• After installation, laying is carried out thermal insulation material. At the same time, it is necessary to ensure reliable protection from moisture ingress, therefore, after the insulation, a layer of waterproofing material is laid.

Note! When laying an electric heating cable, the intersection of its cores is not allowed, especially for resistive devices.

After installing the heat-insulating material, it is advisable to mark the location of the cable, so the risk of damage during repair work will decrease.

Sewer insulation from the inside

There are cases when it is possible to place an electric heating cable only inside. For example, if the system has already been created and the need for heating became clear later (with the onset of cold weather). This setup has some drawbacks. Namely:

• to some extent, the diameter of the pipe decreases;
• increased risk of blockages;
• there may be a short circuit of the cable itself;
• if the system has bends and turns, it will be very difficult to evenly place the heating element inside it.

The cable laying process itself is as follows:

• a special tee-coupling is mounted in the system;
• then the cable is inserted into the pipe itself;
• after that, the tee is sealed and the cable is connected to the power supply.

As a rule, this method is used only in the fight against already formed ice plugs. In this case, inserting the cable into the pipe will help to quickly fix the problem.

When carrying out the installation and further operation of the electric heating cable, it is worth adhering to some recommendations of experts. Namely:

• the length of one strand of cable should not exceed 80 meters;
• before installing the heat-insulating material, check the entire structure for operability;
• it is not allowed to turn on the electric heating cable if it is laid in a bay;
• the cable itself can be connected to a regular outlet or a separate shield;
• when laying, try not to place the cable at sharp corners;
• before starting installation, check the pipes for cracks and holes;
• during installation, follow the instructions from the manufacturer, this will help to significantly increase the service life of the heating cable.

It is better to purchase a self-regulating cable. Such devices last longer and help save energy.

Video

This video shows the arrangement of sewer heating, namely the installation of a heating cable on a pipe:

The climatic conditions of our country are quite severe, in winter the ground can freeze several meters. In the Arctic, permafrost does not thaw even in summer. The heating cable for sewer pipes works much more efficiently than the technology of winding the heating main with insulating materials or burying it below the freezing point. Consider what this product is, its device, varieties and installation procedure on drainage systems.

The electrical element is flexible design, which generates heat under voltage due to the resistance of the metal. The degree of heating depends on the brand of the product and the current strength that is supplied to it.

The heating cable is designed to maintain a positive temperature in sewer system, laid above the level of freezing of the soil or on its surface. Installation of this device requires additional financial costs, but they pay off by reducing the cost of excavation. In addition, drains will be reliably protected from the cold even at extremely low air temperatures.

When heating is needed

Heating of drain pipes is required when they are operated in the cold season. AT without fail it is necessary to maintain heat in them in private houses, summer cottages, baths and other buildings where the sewage system is not deep.

Freezing is fraught with freezing of the draining liquid, blockage of the line and its rupture.

Why does ice accumulate

As a rule, when laying in the ground, sewer pipes are lined with rolled insulating materials. With prolonged contact with frozen ground, the cold reaches the main, the temperature of the walls of which drops below zero. The contact of the liquid with the walls of the sewer leads to the formation of a thin layer of ice, and icicles grow on the top. Gradually, the ice thickens until it completely fills the pipe.

The problem is eliminated in one way - the earth is dug up, the ice is melted with a blowtorch or a gas burner.

Heating cable device

Depending on the type, heating elements have a design of varying complexity, thickness and flexibility.

Products consist of the following parts:

• heat-releasing conductor (wire);
• insulation of cores with high thermal conductivity;
• inner polymer shell;
• wicker screen protector copper wire or foil;
• outer insulating sheath;
• sensors and thermal relays;
• power cord and electrical plug.

Inside modern self-heating systems, a self-regulating matrix of semiconductor materials is installed.

Principle of operation

Heat is generated due to the fact that the wire, which is the basis of the cable, has a certain electrical resistance.

When current passes through a metal, heat is generated. This principle is used in the manufacture of incandescent lamps and heaters. To prevent wasted energy, the cores are insulated with dielectric materials with a maximum degree of thermal conductivity and flexibility. For the manufacture of heating cable is used flexible metal with medium resistance. The heat generated is sufficient to prevent ice formation and melt the insulation.

Advantages and disadvantages

Using electricity to heat sewer pipes has its pros and cons.

The advantages of this method are the following:

1. Security. The cable has a significant margin of safety and is protected from external factors. The relay cuts off the power supply in the event of a short circuit.
2. Ability to create and maintain optimal temperature inside the pipeline. No threat of ice formation inside the highway and its destruction.
3. Ease of installation, no need to carry out time-consuming routine maintenance.
4. Reducing the time for preparatory activities and the costs associated with this.

The disadvantage is the dependence of devices on the supply of electricity. In its absence, it is necessary to suspend the functioning of the sewerage system.

Types of cables for heating

To create a sewer anti-icing system, devices are used different design. They are installed inside the pipe or on its outer side. The choice is determined by the characteristics of the drain system, its diameter and length. Let us dwell on the design of each type of cable that is used to heat the sewer.

resistive

It is a flexible wire covered with several layers of insulation.

The power and resistance of the cable are constant and not adjustable. The price of this type of heaters is low, many consider this a plus. The downside is that the core temperature gradually drops from the entry point to the end point. In addition, there is a high risk of wire burnout during sudden warming and thawing of the soil.

self-adjusting

The cost of this type of device is higher, but the investment is worth it. The design of the self-adjusting system ensures its switching on and off when the set temperature is reached, maintaining it at a constant level throughout the pipeline. Zonal devices are able to heat certain nodes and sections of the sewer.

Shielding

The metal screen is used to protect the electrically conductive part of the cable from moisture. The screen is made of tinned copper, resistant to corrosion. Copper has enough flexibility and strength to withstand external pressure without losing its tightness.

AT budget options heating systems use aluminum.

Products with aluminum screens are laid outside in a straight line.

Power and duration

The power of the heating cable is measured in watts per linear meter per hour. This indicator differs between resistive and self-regulating models. At a voltage of 220-240 volts and maximum temperature 90 ºС average main power is 18 watts. It is easy to calculate how much electricity is required to heat a pipeline 15 m long (namely, this should be minimum distance from the house to the septic tank).

Depending on the settings, the electricity consumption will be 100-270 watts per hour.

Life time

The durability of the cable depends on the materials used in its manufacture and the intensity of operation.

The service life of the products is affected by the correct installation and mechanical impact during seasonal ground movements. Most well-known manufacturers from Asia and Europe provide a 5-year warranty for their products. At the same time, the estimated service life is 15-20 years.

Make your own or buy

If you have a special education and experience with electricity, you can make a heating cable yourself. For this, low-power spirals and wires are used. Metal insulation is carried out using a heat shrink tube. Ready product can be no worse than analogues of industrial production.

However, the time and money spent on the purchase of materials may not bring tangible benefits and savings.

Professionals recommend choosing products with such a power that will provide high-quality heating of the main line at a critical temperature drop. If it is possible to continuously monitor the condition of the cable, then it is advisable to stop at the resistive version.

When the system works offline, it is better to install a self-regulating device from inside the main.

Do-it-yourself cable manufacturing and installation

The best option for the manufacture of home-made heating systems is to use a communication cable of the P-274 brand or its analogues. These products are made up of copper wires and durable insulation, resistant to moisture and mechanical stress. The wire is fed D.C. voltage 6-27 volts. Changing the parameters is carried out using a manual or automatic controller, tuned to temperature changes.

Drawing and diagrams

The drawing is drawn to scale on a computer or a sheet of paper.

On it, it is necessary to schematically display the following design details:

• the beginning of the pipeline;
• the exit of the highway to the well;
• the line of passage of the sewage system;
• corners, tees and taps;
• pipe diameter;
• trench depth.

Based on the created schemes, the calculation is made necessary materials and equipment.

Size calculation

The calculation is given for air temperature - 30 ºС. A change in parameters by one degree entails a similar change in power by a third of a point.

Installation video

Mounting Features

When assembling a sewer heating system, it is necessary to take into account the following nuances:

1. Careful preparation of the installation process. Conducting consultations with experts.
2. The internal cable is pulled through an additional twin, which is installed in the room.
3. Laying the wire of a self-regulating product is carried out only in a straight line. Resistive devices may be wrapped around pipes and fittings.

Service

External parts of the heating system should be inspected regularly for external damage.

The resistance of the heating conductors should be measured monthly. If abnormalities are found, disconnect the device from the mains.

Repair of damaged areas should be carried out using heat shrink tubing, followed by strengthening the solder joint.

Common errors and installation problems

When installing heating systems, such errors are most often made.

1. Installation of heating devices below the freezing point. These are extra and unnecessary expenses.
2. Ignoring additional thermal insulation over pipes. The cable cannot heat them over the entire area, which leads to the formation of ice.
3. Work electrical equipment in continuous mode without sensors and relays. This leads to high and unjustified energy costs.