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September 27, 2016 23:02

Heating water pipe

topic that will be addressed in this publication are interested in more suburban housing owners or owners of private houses, especially if building is equipped with fully autonomous water supply system. extremely unpleasant situation is when the cold snap in the street marked still and that of the open valves stops flowing water.Nothing surprising - if not provided reliable thermal insulation and heating water pipe at one of its sites was freezing, ending or cork, or such significant narrowing of the lumen of the tube, the movement of water becomes extremely difficult.

Heating water pipe

heating waterpipe

This is not only very uncomfortable with the consumer point of view - the consequences could be much worse.If the freezing process does not prevent or stop, then with high probability it can lead to deformation of the pipeline and even rupture of the pipe body.It all ends with a major accident inevitable overhaul of the water supply system.

Freezing pipes lead to serious accidents

freezing pipes with serious accidents

course, always still in the design of the future house and its engineering networks taken steps to prevent a similar situation.Water pipe deepened into the ground below the frost level calculated for a particular area, it becomes imperative reliable their insulation.However, in some cases, these measures are simply not enough.

It is not always possible to place the tube below the level of soil freezing

not always possible to place the tube below the level of soil freezing

typical example - the deepening of the trench simply prevents the rocky ridge, or any concrete structures located below.Vulnerabilities are always lots of water intake - the release of their wells or wells, the point of connection to the city water network.Often ice jams occur in areas lifting pipes to the building, in unheated basements, where it passes through the concrete base and an array of etc .

Similar aqueduct areas require special attention, and it would be better if in these places will be provided for electric heating.Run it - not so difficult, because that modern technologies make it possible to use for this purpose a special heating cable.

How does the water pipe heating

Article Contents

  • 1 How does the water pipe heating
    • 1.1 heating cables resistive action
    • 1.2 self-regulating heating cables
    • 1.3 Video: one of the sets of heating cable for water
  • 2 Installation of the heating system water pipe
    • 2.1 Video: how to switch the heating self-regulating cable
    • 2.2 cable installation on top of a water pipe
    • 2.3 Installation of heatingcable inside the pipe
    • 2.4 Insulation after cabling part

heating principle is based on the conversion of electrical energy into heat by passing current through a special heating cables (similar to the usual all spiral or PETN ).The cable is mounted on the outside or inside of the pipe is located in the most vulnerable areas for freezing.Provide them with the amount of heat sufficient to maintain in the cavity of the pipeline so the lowest possible temperature level, which should eliminate the beginning of the crystallization of water and its transition in solid state.

It is clear that in this case the cable itself should have reliable electricity and waterproofed with a good margin of safety, so that completely eliminates whatever whatsoever probability of rupture, melting, punching stress on the pipeline.

Currently, the customer can choose one of several options for the heating cable:

resistive heating cables action

This kind of cables - the most simple in structure.The conductor is made of a certain alloy with high resistance, and the passage of electric current through it begins exotherm.

Varieties resistive cables

Species resistive cables

Issued they single-core or a dual-core version. Solid under these conditions are applied infrequently - for the simple reason that they necessarily require « loopback » chain, that is, both ends of the cable must come together in one place - at the source of supply. While heating pipes is not always easy to perform, and often - and general impossible.

two-wire in this respect more practical - at one end of a cable connected to the mains, and the other set pin socket, providing a closed circuit.

role of the heat source can perform one conductor - second in this case only serves to provide conduction .Some cables have a heating capacity of the two wires - the power of TV Buddy headsets receptacle achitelno above.

The typical structure of a reactive cable

typical structure of the resistive cable

conductors protected reliable , most of all - a multi-layer insulation, a ground loop - screen.The outer layer of high strength, resistant to external influences PVC jacket.

The positive qualities of these cables include:

  • high performance power and total heat transfer, which is particularly important in the water pipes of large diameter or large quantities of shaped elements, which require heating (tees, flanges, valves etc and . )
  • relative simplicity of design which determines and their accessibility in terms of cost.So, like the minimum power cable can be purchased at the price of 150 rubles per square meter.

have resistive cables and their drawbacks:

  • for economical operation of such a water pipe heating systems require the purchase and installation of additional devices - temperature sensors, control and automatic control units, which will keep the temperature at a given level , including power asnecessary.
  • cable realized certain the meter, and contact terminal sleeve must be installed in a production environment.Independently carry out the cutting of the cable is prohibited.

self-regulating heating cables

This kind of cable has been designed specifically for the operating economy, and is quite different and the device, and the principle of its operation.

The structure and action of the self-regulating scheme semiconductor cable

structure and scheme of activities of self-regulating cable semiconductor

Two metal conductors separated by a special semiconductor matrix, which acts as a heat radiator.The special properties of the semiconductor used provide its maximum Conductive at low temperatures, while increasing their power consumption is reduced significantly.Characteristically, such self-regulation occurs in the process of each particular point along the length of the cable.The temperature along the pipe may be quite different, and thus, maximum heating is carried out at the most vulnerable portions of the pipeline.

advantages of using such a cable are obvious:

  • achieved considerable savings in terms of electricity consumption.When the total air temperature system immediately reacts decrease power consumption.
  • This cable can be purchased in any length - on most of its varieties are provided place cut increments of 200 or 500 mm .

The main drawback of such a system of heating water pipe - high enough price.Thus, even the most inexpensive types can cost about 300 rubles per square meter, while the upper limit is "off scale" value, even for 1000.

water pipe heating system may mean outdoor installation cable or placing it in the cavity of the tube. Each of these technologies has its own characteristics, that is taken into account in the selection of the correct model and the performance of work.

heating cables can be manufactured with a circular cross-section, but for external placement on the tube better suited flattened (tape) form, which is to a greater extent will be in contact with the surface and effectively deliver thermal energy.The power range is also quite wide - from 10 to 60 watts per meter - this should be taken into account in the drafting of the heating system with regard pipe material and the specific conditions of the location of the aqueduct.

There is a rather complicated system calculate the required power, which is used by the specialists at the stage of drafting.However, simplified .In a domestic environment, it is possible to focus on the following parameters:

To install the cable inside the tube is usually sufficient power density of 10 W / m

To install the cable inside the pipe is usually enough power density of 10 W / m

If you plan to heating pipeline placement of the cable in, there will be sufficient power density for this 10 Watt/ m.

For external cable placement on metal or plastic water pipes, based on the following indicators:

- Ø ½ ÷ ¾ inch - 17 W / m;

- Ø ¾ ÷ 1½ inch - 27 W / m.

more powerful heating cables or tapes (for example, 31 W / m) are used in a private building for heating sewer pipes with diameter of 100 mm and above.

The package running water heating system usually includes self heating cable and the "cold" part - a wire to connect a power source."Cold cable" may already be connected with the heating part, but most of this work have to conduct yourself.In this case, can be included in the tubular terminal-adapter and the required quantity of heat-shrinkable tubes of different diameters.In the case of self-regulating cable, coma that should be a special bushing, securely insulating the cut end.

Installed plug - bushing

installed bushing stub

Video : one of the sets of heating cable for water

Temperature sensor with automatic unit (thermoregulation) per set Prospect Ave Practical never come - they have to buy separately.Thermoregulation units are available in different versions - so that they may be similar thermostats warm floor with mounting on the wall ,null, installed in the electrical panel on the DIN-rail by type of conventional machine, mounted directly on the pipe in an easy to care and controlplace.

The thermostat , mounted on DIN-rail

thermostat, mounted on DIN-rail

For self-regulating cables are manufactured compact thermostats that are placed on the "cold" part of the cable, pre-configured power-on when the temperature falls to 5 ° C and off when it reaches 15 ° C.

"Холодный" провод с установленным терморегулятором

«Cool» wire with thermostat set

Construction of water pipeline heating systems require the installation of a separate machine, with estimated capacity of about 25 amperes .Never become unnecessary and the system of emergency protective devices - RCD .

Installation of the heating system water pipe

Prior to installation, be sure to yet again the integrity of the insulation of the cable over its entire length. No any case not allowed cabling with signs of surface damage.

One of the most important operations - switching the heating portion of the cable to the "cold" if it was not provided by the manufacturer. Each model can have its own specific features compounds which must be reflected in the instructions supplied with the kit.The main task - to provide a reliable electrical contact and, yet , to create a multi-layer insulation protection completely eliminates the possibility of the closure and the breakdown voltage to the outside.

example cutting a cable and its connection to the power supply wire shown below in the attached video.

Video: how to switch the self-regulating heating cable

When watching a movie sure to pay attention to the accuracy and reliability installation end of the coupling.

Cable installation on top of a water pipe

  • Average location cable - along the pipe in a straight line.He never placed with the top of the pipe.This is done by two reasons.In the first place, it should be excluded the likelihood of damage due to possible mechanical stress on the pipeline from above (falling objects, tools and etc .) Secondly, the freezing of the liquid is always bottom, and it is this area needs to be maximumheating.
Typical accommodation on the tube cable

typical placement of the cable on the pipe

  • If a cable is not enough for reasons required heating power, allowed several "threads", positioning them as shown in the diagrams:
Different types of cable management on the tube

Different types of cablingtrumpet

  • incoming and otherwise - is placed a spiral cable around the pipe.This can also be done differently :
Methods spiral winding cable

techniques spiral winding cable

- Just obvivaya tube cable with certain step;

- It is not always convenient, and in some cases, simply not possible, the code for space is limited and there is no way to pass under the pipe all the cable bay.Then comes another: leave allowances -loop followed by their wrapping around the tube body in the opposite direction.

  • How to fix the cable to the pipe surface?If using plastic pipes for plumbing, then no options - just an aluminum tape, which will provide maximum heat transfer from the cable to the pipe.When this cable is fixed along its entire length.
Aluminium scotch tape

Aluminium scotch

Thus on particularly problematic areas can be improved heat transfer portion sizing fit aluminum duct tape or even a full pipe wrapping foil still to cabling.

Fixing the cable to the plastic tube aluminum tape

Fixing cable on the plastic tube aluminum tape

  • When installing heating a metal pipe, the cable is fixed to the ring way certain step between the mounting locations (300 mm).Use with the recommended heat-resistant adhesive tape or the plastic cable tie.
Cable Mounting ring method

mount cable ring way

There are features cable management on some nodes running water:

  • When placing the cable on the turns, it should be located as close as possible to the outer radius of the outlet.
Installing the cable on pipe bends

cable installation on pipe bends

  • A lot of heat is always assigned at fixing the pipe to metal supports.These areas require additional loops from below - as shown in the diagram.
Thermal insulation of the pipe on supports

Warming pipe on supports

  • special attention always require massive nodes running water - taps, valves, flanges.It also requires cabling under the special scheme - see picture.