[Equest-users] Asking for help on Fan power and mode of operation input for LEED EAc1 compliance

[Yogendra Shah]

Hello everyone, I'm a new eQuest user and working on my first LEED project.
Fortunately and unfortunately, I am in charge of the energy modeling for the
project. We are a two-man company and don't have many resources or other
coworkers to turn to and figure things out collectively. Any help anyone can
provide would be of much help. I've structured the questions to be specific
and included background info and how I've implemented or believe I should
implement input into eQuest. Other difficulties will be addressed in
subsequent emails with similar structured questions. For your help I thank
you in advance.

The baseline model should have total fan power fixed based on total supply
air volume. There's a section in Ashrae 90.1 G3.1.2.9 that says "Supply Fan
Power. System fan electrical power for supply, return, exhaust, and relief
shall be calculated using the following formulas:
Pfan= 746 / ((1 - e^[-0.2437839 * ln(bhp) - 1.685541]) * bhp)
where,
Pfan = electric power to fan motor (watts)
bhp = brake hoursepower of baseline fan motor from Table G3.1.2.9, where cfm
represents design supply flow rate."
Table G3.1.2.9 has another formula for calculating baseline fan brake
horsepower for buildings with less than 20000 cfm or more than 20000. Our
building is under 20000 cfm so I would select the corresponding formula and
obtain the bhp. I would then plug it in the formula above to obtain watts.
What would I do with this? Would I take the fan power in watts and divide by
our actual cfm for the building to obtain watts per cfm? Where should this
be plugged into eQuest? So far I've found under Air-Side HVAC System
Parameters and under Fans tab there's a text box next to Supply under Design
kw/cfm with "n/a" as the value. If I restore the default of Static in WG, it
allows the input of kw/cfm. Is this where I enter the calculated kw/cfm?
Also fan mode must be set to continuous in the baseline and cycling in the
proposed building. The wizard under HVAC equipment has options between
continuous and intermittant but not sure about the detailed mode. Under
Air-Side HVAC System Parameters and under Fans tab there's a pull down
scroll labeled fan control. Then there's also night cycling. Are these two
related? Not sure where to specify for continuous or cycling.

Thanks again,
Vince
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