Non-existing cooling Fan power for proposed case

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Hi all,

I have an issue modelling spaces not designed with cooling equipment in
LEED. The spaces are considered conditioned (occupied) but only heated in
reality. The only cooling that is considered can come from natural
ventilation or in some spaces from ERV ventilators.

Since the spaces do not fall in the 'heated storage' category of ASHRAE
addenda 'DN', I think its proper to model a system to be the same as
baseline, in my case Packaged VAV.

So, what happens with fan power in the proposed case? What W/cfm should be
modelled since this is a hypothetical system (same as baseline - PVAVS)?

Furthermore, this can be more complex if considering spaces with ERV
ventilators (no cooling), for which I have the W/cfm. Should I include the
hypothetical system's fan power for cooling as well?

Thank you in advance.

Best regards
Nick Patsos
Mechanical Engineer

Nick Patsos's picture
Joined: 2014-01-30
Reputation: 0

It's my sense that the nitty-gritty decisions for such cases remain reliant on some subjective interpretation on the modeler's part. I've added my personal take on your queries [bracketed and in red] below.

The most solid advice I can offer on the matter is to be clear in your documentation. At the end of the day, whatever course you take may be disagreeable to your reviewer (even if inconsequential to the results) - so being clear on your interpretation and application of these rules is cheap insurance to save yourself time/effort later, should you have to make a revision and/or explain your approach to others/yourself.


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Nick-Caton's picture
Joined: 2011-09-30
Reputation: 805