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[EnergyPlus_Support] Re: Boiler efficiency according to ASHRAE (e.g. according to CFR)

I asked about this issue also in a forum dedicated to LEED certification and I had the following answer (non official!):
"No boiler efficiency curve is required for the baseline."
http://www.leeduser.com/credit/NC-2009/EAc1?page=0#comment-28740
Regards



--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, Jim Dirkes <jim@...> wrote:
>
> Dear forum,
> I have not followed this thread closely, but I doubt that it's a simple matter to model a specific boiler's part-load efficiency without a lot of data.  I think some of the condensing boiler catalogs have enough data to make a decent curve, but I don't know if it's common.
> For a Baseline boiler, I agree with Francesco - it's not worth spending a lot of time refining the efficiency of a "fictitious" piece of equipment.  My approach so far is to use the ASHRAE 90.1 required efficiency and also to use a curve that reflects some degradation at low loads.  After I read the AHRI test procedure (and after I wake up the next morning :)) I'll see if that makes sense.
> Thanks for the link Francesco!
> 
> From: EnergyPlus_Support@xxxxxxxxxxxxxxx [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx] On Behalf Of FrancescoP
> Sent: Friday, August 10, 2012 10:02 AM
> To: EnergyPlus_Support@xxxxxxxxxxxxxxx
> Subject: [EnergyPlus_Support] Re: Boiler efficiency according to ASHRAE (e.g. according to CFR)
> 
> 
> 
> Thank you Javed,
> it seems that the test conditions are indicated here:
> http://www.ahrinet.org/App_Content/ahri/files/standards%20pdfs/BTS-2000.pdf
> During the test the "outlet water temperature" has to be maintained at "180°F" (i.e. 82°C). Unsurprising, 82°C is also the hot-water supply temperature for the baseline model according to G3.1.3.3 (ASHRAE 90.1-2007).
> 
> Modeling the thermal efficiency of the baseline model has constant would be a good idea? It doesn't correspond to a real boiler, but to a reference boiler.
> Regards
> Francesco
> 
> --- In EnergyPlus_Support@xxxxxxxxxxxxxxx<mailto:EnergyPlus_Support%40yahoogroups.com>, Javed Iqbal <eee.javed@<mailto:eee.javed@>> wrote:
> >
> > Hi,
> >
> > You can find 10 CFR Part 431 boiler test procedure here. look at page no.
> > 461 .
> > http://www.gpo.gov/fdsys/pkg/CFR-2011-title10-vol3/pdf/CFR-2011-title10-vol3-part431.pdf
> >
> >
> > Check this for Boiler efficiency. ..
> > http://www.designbuilder.co.uk/helpv3/Content/Boilers.htm
> >
> >
> > On Fri, Aug 10, 2012 at 5:00 PM, FrancescoP <direzionecontraria@<mailto:direzionecontraria@>>wrote:
> >
> > > **
> > >
> > >
> > > I'm developing a baseline model for LEED certification. The boiler
> > > efficiency has to respect Table 6.8.1F of ASHRAE 90.1:2007. The thermal
> > > efficiency Et shall be equal to 80% according to the test procedure 10 CGR
> > > Part 431. I'm modeling the boiler using the object Boiler:HotWater. I
> > > imposed the "nominal thermal efficiency" equal to 0,8 but what about the
> > > "normalized boiler efficiency curve"? Any suggestion, please?
> > > Do you have any information regarding the conditions of the test procedure
> > > 10 CFR Part 431?
> > > With Regards
> > > Francesco Passerini
> > >
> > >
> > >
> >
> >
> >
> > --
> >
> >
> > Javed Iqbal, LEED AP, CEA
> > Energy Analyst
> >
>



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