Coaxial chimney (definition)

Coaxial chimney — is a type of chimney in which two pipes are placed one inside the other. This structural element is used to remove flue gases from boiler and simultaneous supply of combustion air. The coaxial chimney ensures efficient and safe removal of combustion products, as well as optimal supply of the boiler with the necessary oxygen.

Coaxial chimney: main characteristics:

1. Structure:
   • Outer pipe: Performs the function of removing exhaust gases from the boiler into the atmosphere.
   • Inner tube: Provides fresh air for the combustion process in the boiler.
2. Function:
   • Flue gas removal: The exhaust gases generated by combustion are discharged through an external pipe.
   • Air supply: Fresh combustion air is supplied through internal piping, ensuring efficient and clean combustion.
3. Advantages:
   • Efficiency: Provides efficient removal of combustion products and air supply, which promotes more complete and cleaner combustion.
   • Safety: Reduces the risk of exhaust gases entering the room, since the exhaust and supply of air occur through separate pipes.
   • Easy to install: Reduces the need for additional ventilation ducts and simplifies installation, especially in cases where it is not possible to install separate pipes for air and gases.
4. Installation:
   • Installation: The coaxial chimney is mounted through the wall of the building or the roof, depending on the design and requirements of the heating system.
   • Integration: Typically used with modern boilers that have built-in systems to control the combustion process and remove flue gases.
5. Application:
   • Gas boilers: Most often used in systems with gas boilers, where it is important to ensure safe removal of combustion products and air supply.
   • Boilers with a closed combustion chamber: Used in boilers with a closed combustion chamber, where direct air supply and gas exhaust through one structure is important.