Chimney for gas boiler

Does a gas boiler need a chimney? Of course! Is it possible to build a chimney for a gas boiler with your own hands? Of course! You only need to study the features of the device of the most common varieties of smoke extraction structures, familiarize yourself with the key requirements for such systems and perform everything in full accordance with the provisions of the manual.

Features chimney device

Regardless of the chosen flue, it will include the following components:

• smoke exhaust pipe;
• feedthrough;
• adapter for connection of a flue pipe with a branch pipe of a boiler;
• clamps and mounting brackets;
• telescopic tube;
• tee with condensate drain;
• taps;
• tip in the form of a cone.
  

  Chimney diagram of the gas boiler

Different materials can be used for the production of the chimney. Familiarize yourself with the features of the most common solutions and make your choice.

Brick chimney

If to judge objectively, then the chimney made of bricks is not even past, but the century before last. Such a smoke extraction system has a complex design and requires serious temporary, labor and financial costs for the arrangement.

In addition, the chimney of brick will be inferior to modern "colleagues" for a number of significant indicators.

Chimney made of galvanized pipe

The construction of the "sandwich" type from pipes is rightfully considered to be one of the most effective and successful variants of chimneys.

To date, manufacturers offer a huge range of such chimneys. Among their advantages, it is necessary, first of all, to note the resistance to aggressive external influences and various mechanical loads.

Directly "sandwich" has an extremely simple structure. It consists of two pipes of differing diameter, one of which is inserted into the other. To fill the gap between such pipes, non-combustible basalt wool is most often used.

Coaxial chimney for gas boiler

Modern version with excellent performance and presentable design. It is made according to the "pipe in the pipe" scheme. It is intended for use with gas boilers the combustion chamber of which is made in a closed type. In this kind of equipment, the air intake for burning gas is taken from the street, and not from the heated room.

Air supply is by means of an external pipe laid through the outer wall of the building. Smoke with impurities is discharged through the inner tube. Such a device is advantageous in that it eliminates the need to install an additional ventilation system.

In addition, the specific shape of the coaxial chimney eliminates the possibility of condensation on its walls, which is particularly important in heating systems operating on gas fuel.

Ceramic chimney

This is a reliable, simple, fire-safe, easy-to-install and affordable construction. Its device is extremely simple. Such a chimney is a ceramic pipe, wrapped with insulating material( usually a mineral wool) and placed in a shell of expanded clay concrete.

Regardless of the chosen type of chimney, the construction of this structure must be carried out in compliance with a number of important requirements.

Requirements for smoke extraction structure

1. The maximum allowable slope of the smoke-generating construction is 30 degrees.
2. The length of the branches to the sides can not exceed 100 cm.
3. The smoke exhaust system must be made without benches.
4. Cross sections are excluded.
5. The maximum number of knees is 3.
6. The allowable radius of curvature is not less than the diameter of the pipe used to divert smoke.
7. At the turns, you need to install a inspection hatch to reset the condensation liquid and clean the system.
8. If a rectangular chimney is to be constructed, the width of one side of it must not exceed the width of the second one by a factor of 2;It is impossible that the product had an extended appearance.
9. At the bottom of the pipe you need to equip the drip and revision.
10. Even non-essential deflections of structural elements are not allowed.
11. When building a chimney, one link of the structure should be worn for a second minimum of 0.5 pipe diameters.
12. The presence of gaps between the elements of the construction is prohibited.
13. There can not be any joints in the sections of the passage of the chimney of partitions and ceilings.
14. The connection of all elements of the system should be as dense as possible.
15. The minimum allowable inclination of the smoke extraction pipe in the direction of the heating unit is 0.01 degree.
16. The inner walls of the pipe should be as smooth as possible, the presence of roughness is extremely undesirable.
17. The total length of the horizontal chimney pieces can not be more than 300 cm for houses under construction and 600 cm for buildings erected.
18. The minimum allowable distance between the pipe and surfaces of easily flammable materials is 250 mm, of non-flammable materials - 50 mm.
19. In places where the chimney intersects partitions and ceilings, it is necessary to make a high-quality thermal insulation.
    

    Chimney height for gas boiler

Special attention should be paid to the requirements for smoke stack height in relation to the roof construction skate. So, the chimney must be taken out of the windpipe and mounted at such a height:

• if the horizontal distance from the ridge exceeds 300 cm - above the imaginary line laid down from the roofing skate to the horizon under a ten-gradient slope;
• if the chimney is removed from the ridge by 150-300 cm - on a level with the ridge;
• if the horizontal distance does not exceed 150 cm - not less than half a meter from the roof ridge.

The chimney must be at least 50 cm above the adjacent roof area. If the roof is flat( combined), this figure should be increased to 200 cm.

Distance from ridge to chimney, m	Height of chimney for gas boiler relative to ridge, m
Up to 1,5	0,5
1,5-3	level
> 3	hold imaginary line at an angle of 10 degrees to the horizon downwards, flush with this line

Step-by-step instructions for constructing the smoke extraction system

The chimney arrangement will be considered using the example of building a sandwich system of pipes. This is the most optimal and universal solution. There are 2 methods of assembling a similar construction: inside and outside the house. Explore both options and select the appropriate one.

Outside the building

The first step. We connect to the nozzle of the heating unit a passing element, designed for laying through the wall.

The second step. Apply the marking to the wall surface in accordance with the dimensions of the passing element and cut out the opening.

Third step. Bring the smoke pipe out of the room.

opening Fourth step. We carefully seal the hole and the pipe passing through it.

The fifth step. Attach a tee with a revision to the pipe, then put a plug

Sixth step. We increase the chimney by adding new links until the required length is reached. Having typed the planned height, we establish on a pipe a tip of the cone form. It will protect the system from precipitation and wind. To fix the pipe to the wall of the building we use brackets. The placement of the fixing elements must not be less than 200 cm.

Seventh step. We strengthen all joints of the structure with clamps. We tighten them with wire or bolts.

The eighth step. We paint the chimney with a special heat-resistant paint and varnish compound. It will ensure proper protection of the material against rust.

Video - Chimney sandwich

Inside the house

Getting started with the preparation:

• we designate in the ceilings and roof the holes for the pipe;
• checking the labels with the dimensions of the branch pipe, we make an opening for the chimney.

Next we are directly installing the chimney.

The first step is .We connect the adapter adapter to the branch pipe of the unit.

The second step. Install the tee and revision.

The third step. We begin to build a chimney.

.knees. In places where the pipe crosses the ceiling we use a special protective sleeve.

Fourth step. We put on the chimney a sheet of stainless steel. In advance, cut out a hole in the sheet that is somewhat larger than the diameter of the pipe. Such a sheet should be on both sides of each overlap.

Fifth step. We strengthen the joints of the structure with clamps.

The sixth step. If necessary, attach the pipe to the girder beams. To do this, we use brackets( every 400 cm) and wall clamps( every 200 cm).

Seventh step. We mount on the exit of the chimney tip( deflector) in the form of a cone.

Insulation of the smoke extraction structure

At the points of contact of the elements of the chimney with easily flammable materials, it is necessary to equip a reliable thermal insulation. To ensure this, cover the branch pipe with basalt wool with a foil layer. Mount insulation with fireproof mastic. Additionally, lay mineral wool along the perimeter of each opening in partitions and ceilings.

At the end of the installation, be sure to seal each seam of the system. To do this, just apply a simple soap solution on the seams. The appearance of soap bubbles indicates a breach of the tightness of the system. Correct any detected problems in the shortest time.

Good work!

Video - Chimney for gas boiler