Heat Pump Efficiencies

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Hi All,

I am still fairly new to equest and I am having a bit of trouble with
setting up my HVAC. I created a building model using the equest wizard and
now I have made a number of changes within the detailed DOE2 interface. The
building uses air source heat pumps for the HVAC and I would like to change
the EER/COP values without going back to the wizard, but I cannot figure
where these values are stored. Is there an easy way to make changes like
that within DOE2?

Thanks,

Michael Shields

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Michael,

Typically equest stores the efficiency of a given piece of equipment as either the Heat Input Ratio (HIR) or as the Electric Input Ratio (EIR). This is under the "Equipment Efficiency" heading on the "Basic Specifications" tab if you open the equipment properties within the detailed interface. The Electric Input Ratio should be the inverse of the COP. I hope this helps. Thanks.

Daniel I. Deese, EI|

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Hi Michael, to modify the EIR (which is in Btu/Btu) in the detailed
mode, click on the Air-Side HVAC icon at the top of your screen, then
double click on the heat pump. Under the cooling and heating tabs you
will find a Unitary Power tab where you can change your EIR.

Regards,

Bassam

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I also found some formulas when tooling around in the archives the other day
and could love to get comments, if any about their utlity:

EIR=(1/EER-0.012167)/((1/3.413)+0.012167)
and
EIR=((1/SEER*0.778+1.4)-0.012167)/((1/3.413)+0.012167)

Anyone remember these that knows the source and utility? Is there one for
HSPF?

Carol

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Carol,

I would bet it is the way eQuest determines, in some instances (don't know which ones), EIR without accounting for fan energy.

Any other thoughts?

Demba.

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Why does this look like the formulae from?the ACM Manual from the California Energy Commission??

John R. Aulbach, PE, CEM

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Carol,

I got the attachment from an eQUEST training CD. Marlin Addison is
listed as the author.

Regards,

William Bishop, EIT, BEMP, LEED(r) AP

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Thanks, Bill. I bet you are right, John, that it did come out of the ACM
manual as did much of DOE2 as I understand it. Do they update that manual I
wonder?

Carol

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