Our building measures the outdoor airflow at the AHU. As we have a constant volume system (fan-coils) with 100% fresh air, from that point onward the airflow is not varied. The balancing of the system was checked and confirmed as part of the commissioning process, thus the volume of fresh air delivered to each zone only changes if the outdoor air volume changes at the AHU.
Do we need to have separate outdoor airflow measurement devices for every zone, or is the installed system level measurement device sufficient to meet the credit requirements?
Dylan Connelly
Mechanical EngineerIntegral Group
LEEDuser Expert
472 thumbs up
January 31, 2012 - 6:55 pm
Measuring OSA at the AHU is sufficient. The airflow to the FCUs will be proportional from that point on based on the balancing.
Lourdes Salinas
THREE Consultoría Medioambiental1 thumbs up
May 10, 2012 - 6:21 pm
Hi Dylan,
Just to confirm, if the entire building is conditioned with 100% OA, do we still require to measure it, even though we already know the volume of air entering the building with the system specs?
Dylan Connelly
Mechanical EngineerIntegral Group
LEEDuser Expert
472 thumbs up
May 11, 2012 - 2:58 pm
Yes you still need to measure the air by some means. Sonrisa Lucero pointed out that "LEED Interpretation #2099 addresses using CTs (circuit transducers providing fan status) for constant volume and 100% OA systems as an alternative to the airflow station to comply with this credit."