Passive "Radiant" / Convective Chilled Beams

Chilled beams have been around for many years however during the last decade, the technology has been further developed and more widely applied in the space conditioning industry.


The latest development in passive chilled beam technology employs both convective and radiant principles which are designed to deliver high cooling duties with minimal air movement within the occupied zone. The radiant quotient now available on the market is typically 40% of the total cooling effect (the other 60% of cooling generated by convection). Therefore, the ability to cool by radiation means that this new technology can provide 40% more cooling at the same air movement velocities when compared to traditional finned coiled batteries. This is ideal for use with offices where there is a requirement to provide the best possible occupancy comfort levels and excellent energy efficiency is required.


Radiant/convective passive chilled beams are designed to be installed free-hanging from the soffit, positioned above a perforated metal ceiling system or as Multi Service Chilled Beam (MSCB’s). Furthermore, a passive radiant/convective chilled beam also offers effective cooling when used with a ceiling system or underplate which is perforated to just 30% free area. Therefore, cooling of up to 270-300 W/m applies to the latest passive radiant/convective chilled beams (60% convective 40% Radiant elements) based upon the comfort criteria recommended with BS EN ISO 7730 CAT B (PPD <20 percent).

More information on Passive Chilled Beam products.

Passive radiant convective chilled beams produces spacial conditioning using both randiant and convective cooling.

Passive "Radiant" Convective Chilled Beam Principles

1 - Chilled water passes through the copper pipework.

2 - All the surfaces of the chilled beam are cooled down.

3 - Air local to the chilled beam is cooled down, as the air cools down it becomes more dense and permeates down through the ceiling system.

4 - The ceiling system below the chilled beam is cooled down by the air stream and via radiant exchange. The ceiling systems is typically 2°C - 3°C lower than room temperature.

5 - Warmer room air is displaced upwards to replace the cooler air which has moved downwards (convective).

6 - The building structure is cooled via radiant exchange.

Radiant Passive Chilled Beams Installed above a Ceiling System

Radiant / Convective based Passive Chilled Beam Installation Example