0% Finance now available. Pay by instalments on orders over £500!
Send Your Plan

Domus CMX-S MEV Unit

More Views

Interest Free EMI
Domus CMX-S MEV Unit
£216.00 including VAT Excluding VAT £180.00
Domus CMX-S MEV Unit


Domus CMX-S 

Previousily known as the Polypipe or Silavent Green Line CMX

At just 125mm in depth, the CMX is one of the most versatile, easy to install and energy efficient MEV solutions available on the market.

Ideal for installation in a wide range of properties, the CMX offers a depth of just 125mm, making it ideal for small ceiling voids or for where space is restricted. Fits into ceiling voids and utility cupboard spaces – horizontally or vertically

The 220x90 duct connectors can be converted to 150 round using additional adaptors if required


  • Variable speed settings
  • Max Airflow of 430m3/h
  • Specific Fan Power (SFP) as low as 0.24 wls
  • Dimensions (mm) 710 long x 340 wide x 125 high
  • Fitted with two 220x90 duct connections allowing quick connection to ducts
  • Recognised in SAP Appendix Q
  • Complies with Building ADF (System 3)
  • Option of wall, ceiling and loft mounting
  • Improved controllability
  • Switched Live Boost connection by light/remote switches.
  • Fully variable normal and boost speeds
  • Ultra quiet - acoustically lined for low noise levels
  • Suitable for a floor area up to 275m²
  • 2 year standard parts warranty: 

How MEV Works

Also referred to as System 3 in Approved Document F of the Building Regulations, an MEV system consists of a centralised ventilation unit that continuously extracts waste, polluted and moist air from wet rooms and can be discreetly positioned in either a cupboard, utility room, ceiling or loft space. An MEV system can be ducted throughout the dwelling and operated by the homeowner through a range of control options.


Typically dual speed, MEV systems provide both low speed continuous trickle ventilation and high speed boost flow when required. Replacement fresh air is drawn into the dwelling through background ventilators i.e. air inlets, located in the living areas.

The potentiometer controlled speed selector allows accurate setting of 3 airflow speeds

The unit has 3 fully variable speeds for trickle and boost, 

A switched live (LS) can also be used to select boost speed 

An additional third speed (purge) is available using a second switched live connection.


PVC outer casing with an acoustic lining is included as standard, ensuring minimum noise levels.


The appliance has a low energy, high efficiency EC backward curved centrifugal impeller fan/motor assembly with sealed for life bearings suitable for +50ºC to -25 ºC.


ceiling, wall or floor Installation is recommended 


•ANC848A Manual LOW/BOOST switch
Manual BOOST selection switch. LOW speed is engaged upon connection of mains supply. Both speeds are manually adjustable at the wiring centre to facilitate Building Regulation commissioning speeds.
Manual BOOST and UNOCCUPIED selection switches. OCCUPIED/LOW speed is engaged upon connection of mains supply. UNOCCUPIED speed is intended to be lower than the OCCUPIED/LOW Building Regulation commissioning speed and should be selected when the property is vacant for extended periods such as holidays in order to save energy but keep the property ‘fresh’. There is no requirement or value in the Building Regulations for this speed and should be set to suit the individual client’s requirement. All three speeds are manually adjustable at the wiring centre to facilitate Building Regulation commissioning speeds.
ANC850A Manual LOW/BOOST/PURGE switch
Manual BOOST and PURGE selection switches. LOW speed is engaged upon connection of mains supply. PURGE speed is intended to be higher than the BOOST Building Regulation commissioning speed and should be selected during periods when exceptional levels of indoor pollution are encountered such overcooked food or paint fumes.

Benefits of working with BPC Ventilation

  • Authorised Domus distributors
  • In-House design service
  • In-House Technical support
  • Specialists in easy to install DIY systems
  • 1000s of products in stock in our own warehouse
  • Large showroom with working units on display
  • Installer network throughout the UK and Ireland
  • All systems comply to all the latest building control regulations 
  • 0% Finance available
Technical Specification

Technical Specification

domus mev flow rates

domus mev wiring