Frequently Asked Questions


What are Radiant Passive Chilled Beams?

Radiant Passive Chilled Beams are a 'hybrid' between a traditional Passive Chilled Beam and a Radiant Cooling Chilled Ceiling. Chilled water is circulated through the Radiant Passive Chilled Beam such as Frenger's 'X-Wing®' unit which consists of a single serpentine sinusoid coil (X-Wing® has no joints in the copper coil to eliminate any risk of leaks) with 4 gilled aluminium fins mechanically joined to each waterway. The fins are equally spaced and run longitudinally to each waterway, thus forming an 'X' cross-sectional profile with a waterway in the centre, hence the name 'X-Wing®'.

As chilled water is circulated through the copper water pipes, the aluminium become colder than the room space, thus cooling any air that comes into contact with the cold surfaces, this is the convective quotient and this represents 60% of the total cooling from the X-Wing® unit. The other 40% of total cooling comes from 'radiant absorption' which cools the occupants and room space without the air movement that is associated with convective cooling, hence higher total cooling allowed with radiant convective cooling (325 W/m) as opposed to traditional convective only cooling which is limited to 225 W/m to avoid excessive air velocities - see 'What is radiant absorption cooling'.

Frequently Asked Questions Chilled Beams Radiant Passive Chilled Beams