Hi Everyone,
We are currently working on a project including an 100% OA AHU providing ventilation to 3 different areas.
The same people (110 people on peak) will be moving between those 3 areas during the day.
Using the table in the form for 100% OA is leading to a very large amount of outside air to provide since the number of people in each area for the calculation is 110.
Actually, we want to size the AHU to provide the required minimum OA for this zone composed of 3 areas and occupied by 110 ppl max. Depending on the need, the adequate volume of air will be directed toward each areas based on CO2 sensors.
How are we supposed to document such a system in the form?
Thanks in advance,
Charline SEYTIER
CEO, Co-owner.ThemaVerde, France
15 thumbs up
October 24, 2014 - 8:04 am
Anyone with insights on this topic? Should just consider one single zone occupied by 110ppl?
Andrew Mitchell, P.E.
PrincipalMitchell Gulledge Engineering, Inc.
LEEDuser Expert
126 thumbs up
October 24, 2014 - 8:25 am
You should input your three spaces with 110 people each (330 total) with a diversity of 33%. That will lower your OA requirement.
Charline SEYTIER
CEO, Co-owner.ThemaVerde, France
15 thumbs up
October 28, 2014 - 3:05 am
Andrew, thank you but there is actually no diversity as the Ahu will be 100% OA.
Andrew Mitchell, P.E.
PrincipalMitchell Gulledge Engineering, Inc.
LEEDuser Expert
126 thumbs up
October 28, 2014 - 8:41 am
Ok. I thought that the 100%OA unit was providing preconditioned air to recirculating units. In that case, without demand contol ventilation or a recirculation mode, you will need to use the calculated flow.
If the areas will not be occupied often, and it's not an exhaust driven space, then it's a good idea to recirculate sometimes or use a time averaged ventilation rate.