exhaust fan schedule

2 posts / 0 new
Last post

Dear eQuest users,

I am trying to model an exhaust fan in a zone and I am trying to make it
turn on only when supply air is delivered to the zone. I tried many options
under the Exhaust Air section of the "Outdoor Air" tab. None of them seems
to make this happen. In all configurations, the exhaust fan seems to have
the same schedule which does not follow the supply air flow. Would you help
me with this question?

I would appreciate it very much,
Thanks,
Best Regards,

Simge Andolsun, PhD

SAndolsun's picture
Offline
Joined: 2013-09-11
Reputation: 0

or would you let me know what would be the best way to model the exhaust
fans in the baseline and as built models as per ASHRAE 90.1 appendix G?
Since the system supply fans are supposed to cycle off at nights in these
models, letting the exhaust fans run continuously during these hours will
increase the unmet hours although there are temperature setbacks in the
system. Also, it would negatively pressurize the building all night which
would increase air infiltration and thereby unmet hours. Thus, it does not
seem realistic to me to leave the exhaust fans on and let the supply fan
cycle off at nights. Would you describe what you think is the best modeling
approach for exhaust fans as per ASHRAE 90.1 appendix G?

Thank you very much in advance for your help,
Best Regards,
Simge Andolsun, PhD

SAndolsun's picture
Offline
Joined: 2013-09-11
Reputation: 0