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NC-2009 EAp2: Minimum Energy Performance

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Baseline Fan Power: PFP and AHU Pressure Rises

January 31, 2011

Rodrigo Perez

ING.
IDIEM

LEEDuser Basic Member

29 thumbs up

January 31, 2011

We’re working on a 20 stories building that is seeking LEED NC v3 certification. This building considers ASHRAE’s #8 HVAC baseline system: VAV w/ PFP boxes. This model considers 1 variable speed fan (AHU) per storey, and n constant speed fan into terminal units (PFP boxes).

Baseline Fan Power is dimensioned based on G.3.1.2.9 for AHU and G.3.1.3.14 for PFP boxes.

Modelling these fans basing on pressure rise and 0.7 total reference fan efficiency, will produce 1470 Pa pressure rise in variable speed fan, and 518 Pa pressure rise in constant speed fans.
These values are extremely higher than common pressure rises projected hence, will present higher energy consumption on baseline fans than a typical fan power design.

Is our baseline fan power sizing correct?

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David Hubka

Director of Operations
Transwestern Sustainability Services

LEEDuser Basic Member

527 thumbs up

February 11, 2011 - 5:42 pm

If your assumptions are accurate and the baseline fan power calculations are correct per the equations outlined in ASHRAE you will be ok.

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FAQs about EAp2:

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