www . refrigerationandaircon . co . za RACA Journal I February 2024 25
Project
All images supplied by Maninga Engineering
The new Flower Hall .
HVAC SYSTEM : FLOWER HALL BUILDING The Flower Hall has an adaptable system :
• Active chilled beams
• Air cooled chiller
• Air handling units ( with EC plug fans – for variable fan drive ) The chilled beam HVAC system consists of several key components working together to provide efficient cooling and heating . Below is a description of each component :
Chilled beams : Chilled beams are the primary components responsible for cooling and heating the space . They are typically suspended from the ceiling and resemble radiator-like units . Chilled beams utilise recirculating water from a chiller to cool or heat the surrounding air . The beams contain a coil through which the heat transfer occurs . The cooled or heated air is then distributed to the occupied space .
Air cooled chiller : The chiller is a crucial component of the chilled beam system . It is responsible for cooling the water that circulates through the chilled beams . The chiller uses a refrigeration cycle to remove heat from the water , lowering its temperature . This chilled water is then supplied to the chilled beams to cool the air passing over the coil . The chiller can be located outside the building , often on the roof , to dissipate the heat generated during the cooling process .
Air handling units ( AHUs ): Air handling units play a vital role in the chilled beam system . They are responsible for supplying fresh air to the space and controlling humidity levels . The AHUs contain filters to remove impurities from the incoming air . They also condition the air by cooling or heating it , ensuring it reaches the desired temperature before being distributed to the chilled beams . AHUs may incorporate additional components such as fans , heat exchangers , and humidifiers to optimise air quality and temperature control .
Piping : Water is moved by piping from the chiller to the chilled beams . Polypropylene ( PPR ) pipes were used due to their durability , corrosion resistance , and ease of installation . These pipes transport the chilled or heated water from the chiller to the chilled beams , allowing for efficient heat exchange and temperature regulation .
Ducting : While the primary cooling and heating in a chilled beam system occurs through the chilled beams , ducting is still required for distributing fresh air from the AHUs to the chilled beams . Ducts transport the air to the appropriate locations , ensuring proper air distribution and ventilation throughout the space . The ducting can be smaller in size compared to conventional HVAC systems since the chilled beams require less air supply .
www . refrigerationandaircon . co . za RACA Journal I February 2024 25