[Equest-users] Supply Air Temp Reset Interpretation Please...?

[PKConsulting via Equest-users]

Yes!  Thanks Shaun- even one count of validation makes me feel not so crazy 😜,  especially from an old colleague.  Thank you- thank you.  Why is there too much room for interpretation on these things?  I accept that the User Manual is helpful in most scenarios- but this is one instance that just seems backwards.  If it is supposed to airflow reset controls,  then why is the section written with "Supply Air Temperature Reset"?

I appreciate your validation of my interpretation.

Pasha
Ph: 308-763-1593

> On Apr 20, 2017, at 8:29 AM, Shaun Martin <smartin at shaunmartinconsulting.com> wrote:
> 
> Hi,
>  
> I think the Standard is quite clear about resetting temperature, and says nothing about modulating airflow.  The user manual seems to be wrong.
>  
> Shaun Martin LEED-AP, BEMP
> Principal
> Shaun Martin Consulting
> #90 – 425 Carrall Street
> Vancouver, BC  V6B 6E3
> p. 604-789-1095
>  
>  
>  
>  
> From: Equest-users [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of PKConsulting via Equest-users
> Sent: Thursday, April 20, 2017 7:12 AM
> To: Jones, Christopher <Christopher.r.Jones at wspgroup.com>
> Cc: equest-users at lists.onebuilding.org
> Subject: Re: [Equest-users] Supply Air Temp Reset Interpretation Please...?
>  
> Thanks for the feedback-  so if the justification for the approach is solely based on the user manual explanation- I can accept that.  I'll cross reference it for the 2007 user manual to put it in my notes.
>  
> I've always used air-flow first as a standard reset for all my design energy models, What is counter-intuitive here is that the title of the Appendix G section specifically states 'reset-temp', so why should we not take the section text literally?  I've always humbly assumed that the ASHRAE standard writers know more than me.  After all these years of creating Baseline conforming models (or so I thought),  this makes me feel lost all over again.  AND is it not possible to apply code standard requirements without the use of the User Manual?   
>  
> Thankful- but-frustrated,
> 
> Pasha
> Ph: 308-763-1593
> 
> On Apr 20, 2017, at 6:48 AM, Jones, Christopher <Christopher.r.Jones at wspgroup.com> wrote:
> 
> I had always assumed temperature first but reading the PNNL 90.1-2010 Performance Rating Method Reference Manual, 3.121 (pdf page 151), it states “For systems 5 through 8, the air temperature for cooling shall be reset higher by 5°F under the minimum cooling load conditions using a reset by warmest zone, airflow first strategy.”
>  
> The manual states that the airflow first strategy minimizes zone reheat coil energy ( or overcooling) and central chiller energy consumption at the cost of possible increased fan energy.
>  
> Unfortunately, the reviewer may have a case.
>  
>  
> <image001.jpg>
>  
> Christopher R. Jones, P.Eng.
> Technical Specialist
>  
> WSP Canada Inc.
> 2300 Yonge Street, Suite 2300
> Toronto, ON M4P 1E4 Canada
> T +1 416-644-0252
>  
> www.wspgroup.ca
>  
> Please consider the environment before printing...
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>  
> From: Equest-users [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Pasha Korber-Gonzalez via Equest-users
> Sent: Thursday, April 20, 2017 3:59 AM
> To: eQUEST Users List <equest-users at lists.onebuilding.org>
> Subject: [Equest-users] Supply Air Temp Reset Interpretation Please...?
>  
> Hello--- I received this note from a fellow energy model reviewer (non-LEED review comment) regarding my Baseline energy model that is supposed to be compliant with Appendix G.  I disagree with what they are saying.  I appreciate your feedback please and verification if in fact I am wrong in how I am interpreting Section G3.1.3.12.
>  
>  
> "We believe TEMP-FIRST supply air reset control strategy is not the correct interpretation of G3.1.3.12 – rather, AIRFLOW-FIRST should be used."
>  
>  
> Thanks!
>  
> Pasha
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