Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page
Ask Your Question

In E+, How create an exhaust fan for toilet/bathroom ?

asked 2018-08-10 02:00:33 -0500

Alexis's avatar

updated 2019-03-05 06:55:36 -0500

dhollman's avatar

I would like to create an exhaust fan in Energy + for the toilet and bathroom. 45 m3/h I did something as below, Is it correct ? I am wondering because when I check the input output reference, they say that "For Natural and Exhaust ventilation, the conditions of the air entering the space are assumed to be equivalent to outside air conditions." Its the contrary of what I want. My exhaust fan takes the air inside and move it outside. More over it increases my cooling capacity

Someone can help me or give his opinion ?

image description

edit retag flag offensive close merge delete

1 Answer

Sort by ยป oldest newest most voted

answered 2018-08-14 10:43:09 -0500

It all depends on the zoning. If the toilets are part of a larger zone that includes exterior openings, then the makeup air is likely to come from outdoors due to additional infiltration. In that case, ZoneVentilation is fine to use.

If the building is zoned so that the makeup air is coming from adjacent zone(s), then use ZoneMixing to move air from one zone to another. For the receiving zone (toilet), an equal amount of air is assumed to leave the zone without any additional input. For the supplying zone, make sure there is enough infiltration (or HVAC outdoor air) specified to make up for the air going to the toilet zone.

And it gets a little more complicated when modeling the HVAC system.

edit flag offensive delete link more


Thank you. I didnt think to the additional infiltration, it could explain the increase of cooling capacity

Alexis's avatar Alexis  ( 2018-08-14 20:07:30 -0500 )edit

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Training Workshops

Question Tools

1 follower


Asked: 2018-08-10 02:00:33 -0500

Seen: 325 times

Last updated: Aug 14 '18