Air conditioning plenums, Pre-designed, Pre-insulated, Lightweight & complete with fixings


and a selection of grilles packages to suit.



"Making split & VRV ducted fan coils easier"


Air conditioning plenums for fan coils, pre-designed, pre-insulated, lightweight with optional grille packages and flexible ducting to choose from for a one stop shop. Please see next page for price lists Click here for price lists for all major manufacturers.

We welcome you to our website where we hope you will be interested in purchasing on line soon from one of our new revolutionary pre-insulated, lightweight plenums with aluminium surfaces and metal flange system made from "20mm rigid phenolic insulation panel" with zero ODP.


Most importantly they are all designed to comply with the ducting guidelines DW144 as detailed on the right. 

This means unlike some very short plenums the slope is 15 degrees from fan coil outlet to round spigots. 

This means high pressure losses which can lead to lack of air flow, possible fan burn out and higher noise levels are avoided.



 We have designed various standard options for the most popular manufacturers of split or VRV ducted fan coils although if you have an application at present please phone, fax or email us for a quotation .

Please contact:-  Tel:- 01235 200849,  Fax: 01235 424277,  Email:

Mitsubishi Plenum

Daikin plenum

Grille box






Pictured above are some of our silver lightweight phenolic foam plenums and side entry shallow grille box with LFD 4 way blow diffuser.

Pictured below a selection of the grilles we offer in our pre-selected grille packages for manufacCO circular grilleturers fan coil units as detailed in our price lists  Click here for price lists 

We at have had 25 years in the contracting side of air conditioning and have seen a requirement for a one stop shop for purchasing supply and return air plenums to save you time and headaches designing them to suit each manufacturers details.

We recognise that small details like supply plenums needing to be insulated and the return air plenums needing to have filter rails to suit the fan coil manufacturers original filters with suitable access panels for service and maintenance all take time designing and organising.

LFD diffuser

 We have taken the time to research all manufacturers data and have site measured certain details so we are confident our plenums will fit each application.  We can also provide shorter rectangular ducts and elbows to suit slimline ceiling void (hotel type) or floor mounted chassis spigots that come complete with loose flanges so the ducting can be easily cut on site to suit the grille.


Swirl diffuser  PDF perforated ceiling diffuserEggcrate grille metalEggcrate grille with filter

 Advantages of plenums "20mm rigid phenolic insulation panel"

  • 100% pre-insulated so need for a second trade to visit site to fit 40mm insulation slab (free insulation).
  • Up to 85% lighter than 20swg sheet so a one man job on site whether at high or low level.
  • Multiple spigot options for each fan coil unit.
  • Outlet spigot choice of male or female to suit ducting or balancing damper connections.
  • Outlet choice of spigots or complete with balancing dampers already fitted.
  • Metal flanges fitted for strength where they connect to fan coil units.
  • Duct gasket fitted at touching points between fan coil and flanges where required.
  • Return air plenums designed to re-use fan coil manufacturers filters (where possible).
  • Return air filters have suitable quick release access panels for future service & maintenance.
  • Fixings and fitting instructions with each plenum.
  • Rectangular ducts for shallow ceiling void and floor chassis fcu available and easily site cut to length.
  • Quick delivery times to your specified address.
  • Very competitively priced