Coaxial chimney. Features of a design. Construction elements Coaxial chimney. Features of a design. Construction elements

Heat in the house is the main component of comfort. Home heating is done in many ways. In apartment buildings it is central heating. But in private homes are installed boilers, working with fire. Such units cannot be operated without a flue device. Traditional pipes do not compete with new equipment. So, An increasing number of homeowners are deciding on the installation of a coaxial chimney.

The coaxial chimney has a special design and can be vertical or horizontal

Features of a design

The concept of "coaxial" implies the presence of two objects inserted along the common axis into each other. Based on this definition, we can say, that the coaxial chimney is a double-circuit design, including pipes of different diameters, which are located inside each other. Collisions of parts are prevented by jumpers present inside the device.

Combustion products are discharged to the outside through the inner tube, and the outside is used to supply fresh air, without which combustion is impossible. Learning, what is a coaxial chimney, we can draw the following conclusion: there is no need to provide a constant supply of fresh air. But for traditional flues it is inevitable. in addition, installation of this device allows you to solve a number of problems, inherent in standard chimneys:

  • increase the efficiency of the system. This is due to the fact, the incoming air is heated by the hot smoke of the inner pipe;
  • the risk of fire in places of contact of flammable surfaces with the flue decreases. Cooling of the inner pipe to safe temperatures is carried out by giving it heat to the outer pipe;
  • due to the high efficiency of the system the fuel is burned, practically, fully. So, the number of unburned particles, emitted into the atmosphere, significantly reduced, because of what it is not polluted. We draw another conclusion: installation of a coaxial chimney makes the boiler more environmentally friendly;
  • combustion process, starting with the supply of oxygen and ending with the removal of gases, occurs in a closed chamber, as a result, hazardous combustion products do not enter the room. Therefore it is not necessary to arrange additional ventilation;
  • the compactness of the device saves usable space;
  • a wide range of chimneys. Find a suitable model for systems of any capacity.

The coaxial chimney consists of two pipes, inserted into each other; one removes smoke, the second is used to supply air to the boiler

The main elements of the coaxial chimney

Consider in more detail the design of the coaxial chimney. It can be called complex only with a big stretch.

  • inner tube, whose diameter does not exceed 80 mm, made of stainless or galvanized steel;
  • the outer tube has a cross section up to 125 millimeters. The specific value of this parameter determines the actual value of the diameter of the coaxial chimney. The outer pipe is made of the same types of steel;
  • knee. Performs the function of a transition element during installation work;
  • adapter. With its help the boiler is connected to the chimney;
  • yoke. It is used for the purpose of providing fastening of elements of a flue of the increased durability.

Useful to know! Although galvanized is cheaper, better still stainless.

This standard set of elements can be supplemented if desired:

  • corrugated pipe. Its use provides more convenient installation of a pipe to a branch pipe of the heating unit;
  • overlay, decorating the entrance of the pipe into the wall;
  • flange for wall laying of pipes.

The standard complete set of a flue includes all details, necessary for its installation

To the flue system, arranged as above, gas companies will not impose any special requirements. Moreover! Requirements for the installation of a coaxial chimney do not provide for the organization of supply and exhaust ventilation. And so that the boiler does not fail, you just need to listen to the recommendations. This applies, first of all, condensate. Remember! It must be directed from the boiler, not to the boiler. To do this, just create a small slope of the horizontal pipe towards the street. Here is another point: without a slope coaxial chimneys in winter are covered with ice crust quite intensively.

However, such a good system has one significant "but": not all boilers produced by modern industry can be connected to such smoke extraction systems. We are talking about models of heating units, whose design is not equipped with a special turbine, which is a powerful fan. It is this element that creates the pressure drop, due to which hot air flies out, and cold from the environment is drawn into the combustion chamber.

Varieties of coaxial chimney

The main criterion for the division of these devices into types is the place of their installation.

  • horizontal coaxial chimney. This type of exhaust pipe for the heater is the most common due to the ease of installation. The coaxial pipe is installed in a hole drilled in the wall and walled up there forever. Such a flue system is very convenient when creating individual heating systems in apartments of high-rise buildings, where the possibility of laying a chimney through the roof is absent. Another advantage of such a technical solution cannot be overlooked. It is, that the organization of a small slope of the coaxial chimney in an apartment building will allow condensate to flow into the street by gravity without the use of additional devices;
  • coaxial chimney of vertical construction. It is most often used when installing boilers in private homes. He is taken outside through the roof. The disadvantages of the vertical coaxial chimney are, that at the stage of installation it is necessary to provide condensate drainage.

The horizontal chimney is more convenient in installation and does not demand special devices for condensate removal

Useful Information! Knowing this problem, the manufacturer at its facilities equips coaxial chimney pipes with a specially designed condensate removal system.

Features of installation and connection to a gas boiler

We already know, that the coaxial chimney can be installed both horizontally, and vertically. The first option is much simpler, but due to poor natural traction it can be realized only for models, equipped with an exhaust fan.

Installation of gas chimneys is regulated by relevant regulations. Basic rules, which should be taken into account when installing a coaxial pipe, presented below.

Horizontal coaxial chimney.

  • buying a set of a similar exhaust system, the choice must be made from its diameter. It must not be smaller than the cross-section of the outlet of the heating unit;
  • in accordance with the regulated installation rules, the maximum length of the coaxial chimney of the horizontal type should be done as follows, so that it does not exceed 3 meters. Some manufacturers, relying on high power exhaust fans, recommend long lengths for their models;
  • install the chimney must be inclined 3? away from the boiler for every running meter of pipe. Compliance with this requirement will create conditions for involuntary drainage of condensate;
  • choose a place for the hole in the wall should be taken into account, so that the distance from it to the boiler outlet was about 0.5… 1 meter. Then the chimney will not freeze inside in the cold in winter;
  • if the boiler is installed near a window, the distance from it to the outer pipe of the horizontal coaxial chimney must be at least half a meter. It is strongly not recommended to remove this element of the flue system under the window. In the absence of another possibility, permissible location of the pipe - at least 1 meter below window level. The distance to the gas supply pipe must exceed half the diameter of the coaxial chimney;
  • the height of the outer pipe above the ground must be at least 2 meters. This will minimize the likelihood of contamination;
  • protruding part of the coaxial chimney, located under the balcony or canopy should be a certain length. It should fit in a semicircle with the center at the point of exit of the lower surface of these building elements from the wall with a radius, equal to the width.

The length of the outer part of the horizontal chimney must be at least 0,5 meters

Vertical coaxial chimney. When installing such a structure, you must pay attention to the following points:

  • performing the assembly of the chimney elbows for the gas unit, each upper one should be inserted inside the previous knee and connected with clamps. Failure to do so will result in condensate seeping through leaky joints, and will begin to flow down the outer wall of the chimney;
  • for convenience of service and cleaning, as well as to collect condensate, the lower part of the structure must be equipped with a tee.

Useful to know! Installation of a deflector (or protective cap) gas discharge to the pipe is prohibited due to the possibility of icing. To protect the system from wind and precipitation, a cone-shaped tip is mounted on the coaxial vertical chimney..

It should be noted that. In addition to use in private homes, there is a collective version of the vertical coaxial chimney in an apartment building. This flue system makes the use of individual gas heaters completely safe. A common chimney is installed at the stage of construction of a high-rise building.

Sequence and features of installation

Anyone can install a coaxial chimney with their own hands, who has basic skills in using power tools. This procedure consists of the following steps:

  • a hole is made in the required place of the outer wall;
  • an adapter is connected to the boiler;
  • the chimney itself joins it with the help of a crimping clamp. If necessary, bring the structure to the wall, the knee is used. Fixing of all elements is carried out by the same crimping clamps;
  • the output of the pipe through the hole at the required slope;
  • sealing cracks with mineral wool or foam;
  • the place of an exit of a pipe is closed by a decorative overlay.

The pipe should be well secured with clamps, and the place of its passage through the wall must be closed with special pads

It is necessary to consider, that each turn of the smoke extraction line requires a reduction in its length by 0,5 meters.

Proper installation of coaxial chimney will eliminate the penetration of carbon monoxide into the living space, dangerous to human health. To characteristic errors, most often typical during the installation of the flue system, the following disadvantages are included:

  • incorrect calculation and incorrect assembly of the exhaust system. This can lead to the penetration of smoke through the joints of individual parts of the channel.
  • insufficient rigidity of the chimney to the wall of the house. This defect is most often fixed due to the use of improper fastening;
  • the owner did not equip his house with thermal insulation between the wall and the roof. Its absence leads to a violation of the temperature regime there, where the chimney passes through the walls and roof.

Leading manufacturers of coaxial chimneys

A large number of companies operate in this segment of the global construction market. Below are just the most popular.

Baxi (Bucks). This company is based in 1866 year in England holding BAXI GROUP, which has united under one "roof" to date 16 enterprises with 7 Western European countries. The central plant is considered to be in Italy. In a year more than comes off his assembly line 500 thousands of boilers, the delivery set of which at the request of the buyer can include a coaxial chimney.

Navien (Navien). This brand is one of the largest manufacturers of boiler equipment not only in South Korea, but also the whole world. Over 80 percent of its products are sold in the Pacific, Japan, China, USA, and starting with 2008 year, it became available in the CIS.

Useful to know! Navien-produced coaxial chimneys are suitable for floor and wall-mounted gas boilers up to 75 kw.

Valiant (Vailant). This German company was founded in 1874 year. It is currently part of the Vaillant Group, headquartered in Germany. This company produces more per year 3 millions of units of heating equipment, if necessary, equipped with a coaxial chimney. The key to long and successful operation of the boiler is compliance with the size of the pipes.