In private houses, where all communications are carried out by hand, pipes often freeze over. During severe frosts, ice plugs up to several meters long-form in them, completely blocking the pipeline lumen. The cause of freezing is the insufficient depth of the trenches and poor thermal insulation of the track. A self-regulating heating cable for heating pipes will help to solve the problem. They stretch it both during the laying of communications and through the existing pipeline.
How self-regulating cable works
The heating wire consists of the following elements:
- two copper conductors of increased cross-section;
- conductive matrix (main heating and regulating element);
- internal polymer insulation;
- copper braid;
- external insulation.
The operation of a self-regulating heating cable for heating pipes is based on the conversion of electrical energy into heat. A characteristic feature of the wire is that it only receives electricity, but does not transmit it. The cord can be cut into sections of the desired length, from 20 cm to tens of meters. It is important to avoid sharp bending and physical abrasion of the copper core.
The self-regulation mechanism of the cable is simple. As the external temperature rises, the resistance of the conductive matrix increases and the heat generation decreases. And vice versa. Thus, a properly laid wire cannot overheat or burn out.
Helpful advice! Buy a cable with a small margin. If it is not enough for winding, then part of the pipe will freeze anyway, and all the work will go to waste. A wire that is too long is distributed chaotically throughout the system, which threatens a fire.
There are three types of heating wires in total – self-regulating, resistive, and mineral insulated resistive.
Self-regulating cable is most widely used among electrical heating systems. Its main advantages:
- the ability to regulate heat transfer without personnel control;
- significant energy savings.
The specified cable is classified by power. Products are produced with a maximum allowable temperature of 70, 105, and 135 degrees. The degree of heating depends on the thickness of the copper cores – the larger the core diameter, the higher the temperature. The energy consumption per meter of wire is about 30 W. It is recommended to connect the cable through a separate transformer. Heating can be carried out on pipelines made of metal, metal-plastic, polypropylene.
The resistive cable is heated by a constant resistance that does not change over its entire length. Such wires are produced in sections of a certain length, which cannot be changed. Each coil is equipped with a clutch. Self-regulation in a resistive system is excluded, therefore, large overspending of electricity is possible. In addition, the cable requires constant cleaning from debris to avoid overheating.
Mineral insulated resistive wires are used for heating objects in corrosive environments – alkaline, acidic, saline. The products can also be used in hazardous areas, at high temperatures and loads.
A self-regulating heating cable for heating pipes is used to supply heat to the following objects:
- Pipelines for various purposes, water pipes, sewerage networks.
- Process tanks, cisterns, tanks with liquid.
- Platforms in front of the cottages.
- Roofs and downpipes to prevent icing.
- Underfloor heating systems.
- Greenhouses and winter gardens.
- Terrariums, aquariums, closed biospheres.
Self-regulating heating cable for heating pipes: installation
The heating element is laid inside or outside the pipeline.
The cable is inserted into the pipe if the communication channel is already underground and there is no access to it. Then, at the point of entry of the cable into the underground network, a saddle is installed with a branch of 1 cm. A pipe insert is screwed into it and a wire is brought in. First, you need to measure the length of the section that needs heating and adjust the size of the cable along with it.
Helpful advice! To heat potable water systems, food grade approved products are required. Typically, the plumbing cable is insulated with a safe photopolymer.
Do not run the heating cord through shut-off valves. If the cable insulation is damaged, a person may be electrocuted while using the water supply.
On overhead or newly laid communications, the cable is laid on top of the pipe. There are two main accommodation options:
- linear. The wire is rolled out, straightened, and laid directly on the pipe. The length of the heating element, in this case, should be equal to the length of the intended section. The method is used for channels of small diameter (up to 50 mm). It is possible to pull several parallel cables along the pipe;
- in a spiral. On pipelines of medium and large diameter, the cable is laid in the form of a spiral.
When winding or pulling a wire along the pipe, it is necessary to ensure that there are no kinks, stretching, compression, chafing, and the passage of the cord through sharp parts. Having applied a self-regulating heating cable for heating pipes, the area is completely wrapped on top with adhesive aluminum tape. The ordinary plastic tape will not work. Further, the pipeline is wrapped with any thermal insulator in the form of half-cylinders. Insulation joints are sealed with mineral wool and sealed with waterproof tape.
Helpful advice! Wrap foil around the pipe before installing the cable. Then the heat will be distributed more evenly.
The cable is AC powered. For a more economical use of electricity, you need to install a relay and a thermostat. Then smart automation, if necessary, will turn the heating on and off by itself.