It depends, but the best way would be to model it as exhaust air in the
zone (air side HVAC). If you are trying to assign a schedule to it, it
gets trickier. You probably want to assign it as a design flow then
(under the airflow tab) and assign a flow schedule to it. You'll need to
specify 100% OA at the system level in this case.
I'd be interested in seeing if there's better ways to do this out there.
Are you going to be modeling constant or variable flow hoods, and will your
zones w/fume hoods be served by dedicated single zone systems or by a single
system? More specifics about the HVAC system(s) would be helpful.
Agree on Vikram's points, except about assigning the exhaust flow under the
airflow tab; it should be added in the outdoor air tab. Let me add that,
from eQuest 3.61e & later, you have an option to specify how the exhaust
flow tracks/is coordinated with supply flow. At the zone level you can
specify an exhaust flow as well as the tracking control. Have a look in the
help files under AIRFLOW-TRACKING. I believe this function was added
specifically to address fume hood modeling.
It depends, but the best way would be to model it as exhaust air in the
zone (air side HVAC). If you are trying to assign a schedule to it, it
gets trickier. You probably want to assign it as a design flow then
(under the airflow tab) and assign a flow schedule to it. You'll need to
specify 100% OA at the system level in this case.
I'd be interested in seeing if there's better ways to do this out there.
Vikram Sami, LEED AP
Sam,
Are you going to be modeling constant or variable flow hoods, and will your
zones w/fume hoods be served by dedicated single zone systems or by a single
system? More specifics about the HVAC system(s) would be helpful.
Agree on Vikram's points, except about assigning the exhaust flow under the
airflow tab; it should be added in the outdoor air tab. Let me add that,
from eQuest 3.61e & later, you have an option to specify how the exhaust
flow tracks/is coordinated with supply flow. At the zone level you can
specify an exhaust flow as well as the tracking control. Have a look in the
help files under AIRFLOW-TRACKING. I believe this function was added
specifically to address fume hood modeling.
Steven Savich, LEED AP
Vikram,
Yes, it's on the downloads page:
http://doe2.com/download/equest/
FWIW, I've been using this version for the past year and a half and found it
to be the most stable version I've used to date.
Scott mentioned that there should be a version 3.63 that's past beta-test
available sometime soon.
Steven
Steven Savich, LEED AP
Systems West Engineers
411 High Street
Eugene, OR 97401-2427
(541) 342-7210
(541) 342-7220 (fax)