Concentric CLV Systems


  • The concentric CLV system is a collective chimney system especially for apartment buildings. It brings combustion air to the boilers on each floor and evacuates the individual flue through one common flue duct.
  • The PP rigid inner ducts are suitable for condensing gas and oil boilers with a maximum flue temperature of 120 °C. The outer ducts are made of galvanized steel. The system has a H1 tightness class which enables operation with positive pressure. This reduces the required diameters compared to a negative pressure system.
  • T-pieces with 1 or 2 boiler connections (90° or 180°) are available. Each T-piece contains a compensator to absorb the elongation and shrinking of the PP flue pipes due to temperature variations.
  • A special ring in the T-piece ensures that condensate flows back to each individual boiler. This limits drying-out of boiler siphons which are out of operation.
  • A telescopic pipe makes it easier to adjust the length to the height of the room.
  • An optional inspection opening at the bottom guarantees an easy access.

Features and benefits

  • For multiple boiler installation (positive-pressure)
  • Room sealed (type C) operation
  • Connection up to 20 boilers
  • Maximum 2 boilers per floor
  • Reduced diameter for the flue pipes
  • Telescopic pipes for easy adjustment to room height
  • Special ring in T-piece limits drying-out of boiler siphons

Quick Facts