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Domus CMX-S MEV Unit

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Domus CMX-S MEV Unit
£255.36 including VAT Excluding VAT £212.80
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

Download Documentation
Domus CMX Catalogue


World Wide Delivery Service

BPC have years of experience in delivering equipment around the UK and other Worldwide destinations. Our dedicated customer service team work hard to ensure the highest standards are met so that your goods arrive on-time and in pristine condition.

Our market knowledge and experience allow us to match our service to meet your requirements swiftly and safely.

Free Delivery

We offer free delivery on any order over £200 to any mainland UK or Ireland address

Worldwide Delivery

Worldwide delivery is possible on almost all our products at very low delivery costs, Delivery to countries outside the EU are normally delivered to the nearest customs office, port or terminal for the purchaser to collect and complete custom clearance

Please contact us to confirm shipping cost and availability 

End-To-End Support

Delivery is available within 48 hrs in most cases for hundreds of stock items. Our customer service teams always contact customers to confirm when delivery is required and to check that the goods can be received. Any problem from the customer’s end is accommodated and arrangements changed.

These checks are part of a unique commitment to building relationships with customers, understanding their specific delivery needs and responding to them positively and promptly.

We deliver on Service

  • Key components such as Ductwork and fittings plus the most popular selling MVHR units are kept in stock in our UK-based warehouse, which means that you receive the best possible delivery dates.
  • All goods are expertly packed by a professional team so that your equipment is received in pristine condition ready for installation.
  • All deliveries co-ordinated to suit your specific requirements and construction programme.
  • Specialist team fully conversant with all documentation requirements for a smooth order and delivery service.

Delivery Costs

Please click here to view delivery costs

Delivery Partners

We only use the couriers with the highest standard of service that include

  • DPD
  • Parcelforce
  • Pallet Network
  • Speedy freight

Delivery Serivices