Background Ventilators


Background Ventilators

For use with intermittent extract ventilation and Mechanical Extraction Ventilation (MEV) systems.

Description Boxed Code Contents
Kit - Background Ventilators - Telescopic - Round - Diffuser - Env Filter - Ø100mm** 2404W
Accessories to 2404:
Environmental Filter 40AF -
Pollen Filter 40AFP -
Wall Liner Acoustic Treatment 4SLWL -
Kit - Background Ventilators - Telescopic - Round -  Damper - Ø125mm 508W 5902W


**2706 (Equivalent area 2857mm²). 7.1l/s @ 10Pa exhaust air heat pump specific.

Kits are available with different terminal colours. Where kit terminals are available in different colours, the component code is marked with an asterisk(*).

To visit the page of each Domus duct product type, please use the navigation list shown in the left hand column of this page.




Selecting the correct specification of background ventilation is explained in section 5 of Approved Document F of Building Regulations (p19).

Background Ventilators should be located to avoid draughts, typically 1.7m above floor level.

Background Ventilators should be located in all rooms with external walls.

  • At least 5000mm² total equivalent area of ventilation should be provided in each habitable room and 2500mm²  equivalent area in each wet room
  • For rooms with no external walls, detailed guidance is given in paragraphs 5.14 to 5.16 of Approved Document F

To download installation insutructions for the 2404 air supply kit, please click here.

General Technical Installation Tips:

  • To ensure appliance efficiency and reduce any system noise:
  • Choose the shortest and most direct routes
  • Minimise the use of bends and use 2 x 45° instead of 90° bends wherever possible
  • Seal joints with DDSEAL acrylic sealant
  • Use rigid round duct wherever possible
  • Use the largest appropriate size of duct
  • Avoid using flexible hose wherever possible
  • Check the extraction capability and connection