Projects
1
2
Once the duct branches off onto the floor , it is equipped with a pressure control damper , which , via the control system will ensure that the branch duct pressure remains constant as the flowrates fluctuate on building demand . Swirl type variable air volume diffusers are strategically placed throughout the open plan floors to ensure adequate air distribution and eliminate draft effects .
The diffusers have integral temperature sensors that compare the actual room conditions to that of the set-point . Should the room conditions deviate from the set-point , the diffuser will react by supplying more or less conditioned air to the space , hence varying the air volume of the system .
Upstream of the diffuser , the pressure control damper and the AHU speed will modulate to meet set criteria as the system operates . All parameters are pre-set , and no manual operation is needed . Return air is drawn from the open plan areas via louvres located in the clearstory window line in the common atrium .
The atrium is served by dedicated AHUs with air distribution achieved by linear diffusers strategically placed along the perimeter of the atrium and on bridges crossing the space . High volume radial type diffusers are also provided in the ceiling level of the atrium .
Boardrooms and large meeting rooms are served by dedicated 4-pipe fan coil units with treated fresh air supplied by fresh air tempering AHUs on the roof . Each boardroom / large meeting room is equipped with a
3
26
RACA Journal I November 2020
1 . |
Secondary chilled water pumps . |
2 . |
Ice storage vessels and ice inventory meter . |
3 . |
Chiller piping connections . |
www . hvacronline . co . za