CLIENT: Magnum House, MCR Property Group

Magnum House is a listed building located in Manchester City Centre, comprising nine floors of office space.

Airtech was awarded the contract to refurbish and upgrade the mechanical services, including:

  • Installation of new Mitsubishi 3-Pipe VRF air conditioning
  • Installation of a Gas Fired Air Handling Unit to provide fresh air ventilation
  • Installation of a Car Park Ventilation system
  • Installation of Extract Systems throughout the building
Air Conditioning

Fresh air supply to the various office areas in the building is via a series of ceiling mounted Mitsubishi ultra-thin concealed VRF fan coil units. The air is pre-cooled by the 4-stage DX coil situated in the air handling unit, AHU, before it is distributed by sheet metal ductwork to the various fan coil units on each floor.

A series of VRF condensers are installed in the external areas. The refrigerant pipework runs from to the various levels and connects to BC controllers before running to the various fan coil units situated in the ceiling void.  The VRF units are complete with a condensate pump allowing drainage to a local SVP.


The ventilation system installed was of the centralised type with the air supply and extract

requirements being served by a dedicated air handling unit, AHU.

The AHU was complete with appropriate bag filters and dampers and contains an indirect natural gas fired heater module and 4-stage DX cooling coil c/w eliminator. Appropriate attenuation was provided in the ductwork entering and leaving.

Air was distributed into the rooms via a series of sheet metal ductwork, which terminates at various fan coil units on each floor. Tempered air is distributed into the rooms via grilles.

A twin extract fan was installed and provides the necessary dirty air extraction for the building. A series of ducted toilet extract grilles was installed and allows for appropriate air extraction. Supply air to the toilet core is provided by the AHU and distributes in the toilet core at each level via a series of toilet supply grilles.

The mechanical supply and extract ventilation system is complete with external weather louvres, air handling plant, silencers, ductwork, fittings, supports, fire dampers, access doors, volume control dampers, flexible ductwork, pan adapters, diffusers, grilles, thermal insulation, etc.

Car Park Ventilation

The car park ventilation system comprised of the following

  • 4 No. Jet Fans
  • 2 No. Extract Fans
  • 3 No. CO Heads
  • 1 No. Control Panel Wiring System

The specialist car park ventilation installer (Flakt Woods) supplied and installed all the necessary equipment for the system. This included the equipment listed along with the associated fire rated ductwork. The car park ventilation system provides adequate air extraction from the space to control the amount of contaminates in the air.


A PC Based controls system was installed, providing energy monitoring capabilities and zoned floor by floor control.