EZ-Fit Flexible Vertical Balanced Flues (Red System)

Grant EZ-Fit Red SystemThe Grant Red System is the flexible balanced flue solution to nuisance pluming and cold draughts. It is designed for Grant condensing boilers up to 26Kw (90,000Btu/h) and allows an existing masonry chimney to be utilised rather then re-site the boiler and pipework.\

Flexi Kits

The Red System is supplied in two parts: Pack 1 consists of the boiler connector, adjustable extension, bottom adaptor, terminal, plate and clamp. Pack 2 comprises two lengths of flexible vertical flue pipe (stainless steel and polypropylene) and is available in lengths for 6, 8, 10 and 12 metres.

Extensions and elbows

The flexible vertical balanced flue kits share the same EZ-Fit flue extensions and elbows as the Grant ‘White System’. This unique quick fit connection arrangement ensures easy assembly thereby reducing installation costs. The maximum vertical straight length of the flue, from the top of the boiler to the top of the terminal, is 20 metres – using no more than four 45º elbows.

One metre of straight flue length should be deducted for every elbow used. If the flexible liner has to pass around an offset inside the chimney, two metres of straight flue length should be deducted to compensate for this i.e. equivalent two 45º elbows. Flue extensions cannot be cut, adjustable extensions should be used where required.


  • Suitable for Grant Vortex boilers up to 26kW
  • Maximum total flue length = 20 metres (using no more than four 45° elbows)
  • Available in 6, 8, 10 and 12 metre packs
  • Quick and simple to install
  • Flue pipe diameter = Inner: 80mm Outer:125mm
  • Shares the same flue extensions as the White System
  • Extensions available in 225mm, 450mm or 950mm fixed lengths and a 275-450mm adjustable length
  • Optional 1 metre extended flue terminal
  • Pitched or flat roof flashings in aluminium or lead available
  • Possible to create offsets in straight flue runs by using our 45° elbows and extensions

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