Let's say you have a proposed zone being conditioned by an RTU with only a supply fan and you also have a small exhaust fan exhausting air directly from a toilet room, and that's the extent of your building HVAC systems. What is the proper way to model the toilet exhaust fan power for the baseline? Is it already accounted for in the appendix G fan power calc for the baseline RTU? Or do you add the proposed exhaust fan energy to the baseline model? Or do you do another Appendix G fan power calc just for the exhaust system?
Also, does this exhaust fan need to be stated as a separate system in the Tables 1.4 Excel sheet or is it just considered part of the RTU system, even though it's not directly connected to the RTU like a powered exhaust fan would be?
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5906 thumbs up
November 5, 2013 - 12:18 pm
The bathroom exhaust is included in your baseline fan power calculation.
If it is an exhaust fan serving an unconditioned space then it modeled identically to the proposed.
Matt Scott
EngineerN.E. Fisher & Associates, Inc.
18 thumbs up
November 5, 2013 - 1:18 pm
Understood. Thanks!
Julio Fernandez Amodia
5 thumbs up
March 14, 2023 - 4:49 am
Hi there,
I wonder if the bathroom exhaust fan shall be included in the energy model or could be calculated on an excel sheet and later added to the totals. Could you share your approach?
Thanks