Varieties of chimneys for solid fuel boilers

The efficiency of the chimney for a solid fuel boiler determines its performance, draft and safety for people living in the building. The combustion of fuel produces smoke and soot. These substances can clog the pipe and cause fires when they accumulate in large quantities. The chimney for a solid fuel boiler must be strong, fireproof and durable. The condition for achieving these criteria is the correct choice of material and adherence to the installation technology.

Types of chimneys for a solid fuel boiler

Chimneys for the boiler TT can be made independently or you can purchase products ready for installation. The choice is determined by the design features of the furnace and the building, your own abilities and financial capabilities.

Pipe material options for solid fuel heating boilers:

• Metal. Dark iron structures are durable and affordable. The circular channel provides good traction. The downside is that the metal quickly rusts under the influence of acid formed by the interaction of soot and condensate.
• Brick. It is a time-tested material that is resistant to the highest temperatures. Can be used to build a chimney for a coal boiler. However, the brick quickly collapses from changes in moisture levels.
  
• Refractory glass. These pipes are considered to be the best. They withstand high temperatures, do not react to acids, and soot does not form on the inner walls. The only downside is the high cost of production.
• Ceramic pipes. Chimneys are resistant to strong heat and corrosion. Smooth walls do not collect soot, which contributes to efficient boiler operation and increased safety.
• Asbestos-cement pipes. The products are inexpensive and easy to install. However, they do not withstand strong heating, they can be installed in long-burning furnaces and in sections of the chimney where the temperature drops to 350 degrees.
• Stainless steel. Such pipes tolerate intense heat well, even from coal. The products are strong, reliable and durable. However, over time, they can also become a victim of corrosion.

At the place of installation, chimneys are divided into internal and external types. The choice is determined by the construction of the building and the capacity of the heating equipment.

Indicators when choosing a chimney

Manufacturers indicate recommendations on the diameter of the chimney pipe for the boiler in the documentation with which the products are completed.

The following criteria are used to determine the suitability of the flue gas discharge device and the heating equipment:

• Pipe height. The larger it is, the better the traction will be. But this will lead to an increased wind load and an increase in the length of the plane of contact with the combustion products. The minimum value is a cut height of 100 cm above a flat roof or 50 cm above the ridge of a gable roof.
• Section. The best option is a circle. Broken lines reduce traction, and carbon deposits build up in corners, which promotes the formation of corrosive acids.
• Temperature threshold.It should be 20-30% higher than the temperature produced by the selected fuel. Wood burns at 300 degrees, and coal can create heat up to 900 degrees.
• Durability. This quality is due to the material's resistance to corrosion and its hygroscopicity.
• Internal area. Ideally, it should match the boiler nozzle. An increase in the diameter leads to a decrease in thrust, and a decrease in the diameter makes it difficult to remove the combustion products.

All these requirements are met by ceramic, glass and stainless steel pipes.

When carrying out design and calculations, you need to take into account the cost of materials and soberly assess your capabilities for their installation.

Basic installation rules

When building a chimney for a solid fuel boiler, it is recommended to adhere to a number of rules that will ensure the efficient operation of the heater.

The rules are as follows:

• Locate the pipe at a safe distance from combustible surfaces and objects. If this is not possible, protect them with shields made of materials with low thermal conductivity.
• Avoid the formation of straight and sharp corners in the route of the highway. These areas reduce traction and collect dirt and grime.
• If the height of the pipe is more than 150 cm, stretch marks should be made to prevent it from overturning or breaking by strong winds.
• A condensate collector must be installed below the first section of the pipe. This will prevent it from clogging up with solid deposits.
• If the shape of the pipe does not match the configuration of the flue, an adapter must be used. Seal the remaining cracks with heat-resistant sealant.

The main requirement for the structure is its fire safety and the absence of the risk of smoke pollution in the premises.

Chimney installation recommendations

The installation of the chimney must be carried out in a certain sequence so that the structure is strong and stable.

This activity consists of the following stages:

1. Preparation of the base and installation of a solid fuel boiler.
2. Marking for making holes, fixing clamps and spacers.
3. Drilling a hole in the wall or openings in ceilings, depending on the chosen installation method.
4. Sealing of passages with heat-insulating plates with pre-made holes for the pipe.
5. Chimney assembly. The technology is selected in accordance with the selected material.
6. Sealing the remaining slots. Installation of a condensate collector. Installation of the cap on the upper cut of the pipe.

Checking the correctness of the installation is carried out by kindling the hearth with newspapers or grass, checking all joints for the appearance of smoke.

DIY brick chimney

A brick chimney for a solid fuel boiler is quite large, but this is not a drawback. The vertical structure has a good heat capacity and can be used for additional heating of the room, the water circuit and heating the attic.

Construction is carried out in the following sequence:

1. A solution is made from a mixture of sand and clay in a 3: 1 ratio.
2. A corpulent fired red brick is being prepared, the quality of the stones is being checked.
   
3. A tower is laid out with a side of 2-2.5 bricks and a thickness of 1 brick. The thickness of the mortar is taken 1.5-2 cm. For 4 heights of the stone before the overlap, the laying is suspended.
4. The fluff is laid out to reduce the thrust and temperature of the exhaust gases. After the passage of the ceiling, the tower begins to narrow by the width of 1/8 of a stone in each row.
5. The masonry is removed through the roof, in this place the next expansion (otter) is made, the total height of which is 6 rows.
6. Manufacturing of a deflector that prevents air turbulence from entering the pipe.

In conclusion, heat and waterproofing works are carried out, after which a control firebox is performed.