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[EnergyPlus_Support] Re: PSZ-AC w/district heating? AirLoopHVAC:Unitary:Furnace:HeatCool only has gas or



There was no COP discrepancy. The I-P eddition gives the efficiency in EER and the SI eddition gives the efficiency as COP. 1Wh = 3.412 Btu --> EER = 3.412 COP

Thanks again

--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "jeannieboef" <jeannieboef@...> wrote:
>
> That helps more than you know. I'm not sure what's going on with the COP indescrepency between SI and P-I edditions, but I'll look into it. Thanks for the heads up.
> 
> --- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "James V Dirkes II, PE" <jvd2pe@> wrote:
> >
> > Dear Jeannie,
> > 
> >  
> > 
> > Focusing my thoughts..
> > 
> > .         Normally a System 3 serves a single thermal zone, so the zone and
> > system capacities are identical
> > 
> > .         If your system capacity is < 19kW (per E+, not the actual
> > equipment!), you'll fall in the smallest ASHRAE 90.1 capacity range, so the
> > efficiencies will be as shown below
> > 
> > 
> > 
> > .         As you can see, I have the IP version of the Standard, however
> > your 3.18 SCOP value does not quite line up with these values
> > 
> > .         In other regards, I think that you are "bang on".  Keep in mind
> > that the baseline system is fictitious and has very little to do with the
> > real system.  You are clearly (for System 3 and this 19kW system) a "single
> > package", "all" heating.  Use the 9.7 or 13.0 EER depending on whether your
> > project is filing as built before or after 1/23/06.
> > 
> >  
> > 
> > I hope that helps!
> > 
> >  
> > 
> > The Building Performance Team
> > James V. Dirkes II, P.E., LEED AP
> > 1631 Acacia Drive NW
> > Grand Rapids, MI 49504
> > 616 450 8653
> > 
> >  
> > 
> > From: EnergyPlus_Support@xxxxxxxxxxxxxxx
> > [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx] On Behalf Of jeannieboef
> > Sent: Monday, August 30, 2010 10:12 AM
> > To: EnergyPlus_Support@xxxxxxxxxxxxxxx
> > Subject: [EnergyPlus_Support] Re: PSZ-AC w/district heating?
> > AirLoopHVAC:Unitary:Furnace:HeatCool only has gas or
> > 
> >  
> > 
> >   
> > 
> > In my case you're bang on. very small LEED project, purchased heat.
> > LEED's brought out some new guidlines which divert (on purpose) from ASHRAE
> > on some small points. I referenced the document earlier. gas is no longer an
> > option in my case, hence the whole water loop coil effort. The simulation I
> > set up seems to be running and I'll check it tomorrow for the outputs, but I
> > still don't know exactly how to match up the system no 3 with the min. eff
> > tables in chapter 6 of the standard. That's why I put down my best guess for
> > your opinion on which tables apply to PSZ-AC w/district heating equipment.
> > 
> > --- In EnergyPlus_Support@xxxxxxxxxxxxxxx
> > <mailto:EnergyPlus_Support%40yahoogroups.com> , "James V Dirkes II, PE"
> > <jvd2pe@> wrote:
> > >
> > > Dear Jeannie and Vinay,
> > > 
> > > 
> > > 
> > > . I have not followed this thread of conversation from the
> > > beginning, and cannot give you too much time to look it up. but I'll try.
> > > 
> > > . Assuming that you are involved with a LEED project, your baseline
> > > HVAC is PZ-AC only if the building 
> > > 
> > > o has 3 floors or less
> > > 
> > > o is also less than 25,000 sq.ft.
> > > 
> > > o and the proposed system is fossil-fueled or purchased heat
> > > 
> > > . That means your baseline system should be defined with a DX
> > > cooling coil and fossil-fueled heating coil. I think that I would use a
> > gas
> > > coil for the baseline; it's simpler to create (no water loop).
> > > 
> > > . I use component efficiencies appropriate for the modeled system
> > > (the entire air or water loop, not individual zones). Baseline systems
> > > require autosizing per ASHRAE 90.1, so you will have to get the model
> > > running, then check the reports to see what capacity E+ has determined,
> > then
> > > adjust your input efficiencies as needed to match the 90.1 requirements.
> > > 
> > > . The proposed system will be exactly as designed by you (or
> > > whomever is the designer), including components and efficiencies.
> > > 
> > > 
> > > 
> > > The Building Performance Team
> > > James V. Dirkes II, P.E., LEED AP
> > > 1631 Acacia Drive NW
> > > Grand Rapids, MI 49504
> > > 616 450 8653
> > > 
> > > 
> > > 
> > > From: EnergyPlus_Support@xxxxxxxxxxxxxxx
> > <mailto:EnergyPlus_Support%40yahoogroups.com> 
> > > [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx
> > <mailto:EnergyPlus_Support%40yahoogroups.com> ] On Behalf Of jeannieboef
> > > Sent: Monday, August 30, 2010 9:00 AM
> > > To: EnergyPlus_Support@xxxxxxxxxxxxxxx
> > <mailto:EnergyPlus_Support%40yahoogroups.com> 
> > > Subject: [EnergyPlus_Support] Re: PSZ-AC w/district heating?
> > > AirLoopHVAC:Unitary:Furnace:HeatCool only has gas or
> > > 
> > > 
> > > 
> > > 
> > > 
> > > Mr. Dirkes,
> > > 
> > > I'm also having trouble pinning down the required efficiencies.
> > > 
> > > I'm guessing the following at the moment:
> > > System Type: Packaged rooftop air conditioner
> > > Fan Control: Constant Volume
> > > Cooling Type: Direct Expansion (DX)
> > > Cooling Capacity: (zone dependant, ranging from 5.2 kW to 0.1 kW)
> > > 
> > > Min Efficiency Requirements as per Table 6.8.1A Air Conditioners,
> > > Equipment Type: Air Conditioners, air cooled (as DX coils are air cooled),
> > > Size Category: <19 kW (rated cooling capacity?),
> > > Heating Section Type "All"
> > > Subcategory or Rating Condition: Single Package
> > > Minimum Efficiency (cooling?): 3.18 SCOP (as of 1/23/2006)
> > > 
> > > Heating Type: Normally Fossil fuel furnace, but as per Treatment of
> > District
> > > or Campus Thermal Energy in LEED V2 and LEED 2009 - Design & Construction,
> > > August 13 2010 - Purchased District Heating
> > > 
> > > Heating Capacity: (zone dependant, ranging from 4.4 kW to 0.1 kW)
> > > 
> > > What will the heating coil efficiencies be? I see options for implementing
> > > cooling coil efficiencies (using the modifier curves as per DOE-2.1E) and
> > > part load functions, but not for a hot water coil. Is there any
> > requirement
> > > for how much heat must be transfered from the coil to the air?
> > > 
> > > --- In EnergyPlus_Support@xxxxxxxxxxxxxxx
> > <mailto:EnergyPlus_Support%40yahoogroups.com> 
> > > <mailto:EnergyPlus_Support%40yahoogroups.com> , Vinay Devanathan
> > > <vinay.devanathan@> wrote:
> > > >
> > > > Mr. Dirkes,
> > > > 
> > > > Do we have to use only coil:hot water or can we also use coil:gas?
> > > > 
> > > > Thank you.
> > > > 
> > > > On Aug 30, 2010, at 6:59 AM, "James V Dirkes II, PE" <jvd2pe@> 
> > > > wrote:
> > > > 
> > > > > Dear Jeannie,
> > > > >
> > > > >
> > > > >
> > > > > Just construct an Air Loop which has a fan, (hot water) heating coil 
> > > > > and DX cooling.
> > > > >
> > > > >
> > > > >
> > > > > There is nothing magical about the Furnace:HeatCool object; it just 
> > > > > has a cycling (on:off) fan, a heating coil and a cooling coil.
> > > > >
> > > > >
> > > > >
> > > > > The Building Performance Team
> > > > > James V. Dirkes II, P.E., LEED AP
> > > > > 1631 Acacia Drive NW
> > > > > Grand Rapids, MI 49504
> > > > > 616 450 8653
> > > > >
> > > > >
> > > > >
> > > > > From: EnergyPlus_Support@xxxxxxxxxxxxxxx
> > <mailto:EnergyPlus_Support%40yahoogroups.com> 
> > > <mailto:EnergyPlus_Support%40yahoogroups.com> 
> > > > > [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx
> > <mailto:EnergyPlus_Support%40yahoogroups.com> 
> > > <mailto:EnergyPlus_Support%40yahoogroups.com> ] On Behalf Of jeannieboef
> > > > > Sent: Monday, August 30, 2010 4:40 AM
> > > > > To: EnergyPlus_Support@xxxxxxxxxxxxxxx
> > <mailto:EnergyPlus_Support%40yahoogroups.com> 
> > > <mailto:EnergyPlus_Support%40yahoogroups.com> 
> > > > > Subject: [EnergyPlus_Support] Re: PSZ-AC w/district heating? 
> > > > > AirLoopHVAC:Unitary:Furnace:HeatCool only has gas or
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > Is everyone on holiday?
> > > > > --- In EnergyPlus_Support@xxxxxxxxxxxxxxx
> > <mailto:EnergyPlus_Support%40yahoogroups.com> 
> > > <mailto:EnergyPlus_Support%40yahoogroups.com> , "jeannieboef" 
> > > > > <jeannieboef@> wrote:
> > > > > >
> > > > > > anybody have an idea as to how to do this?
> > > > > >
> > > > >
> > > > >
> > > > >
> > > >
> > >
> >
>




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