Scroll chiller curves in DOE-2 library

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I am modeling a new air-cooled scroll chiller, but eQUEST doesn't have a "scroll" chiller type. I'm guessing the "screw" chiller type is the closest option. Out of curiosity, I searched the library and found the following performance curves:
ScrollChlrAirCoolEIR-fPLR
ScrollChlrAirCoolEIR-fCHW&OAT
ScrollChlrAirCoolCap-fCHW&OAT

Using these curves greatly reduced (by 33%) the cooling energy vs. the default ScrewAir-EIR and ScrewAir-Cap curves. Did I find the eQUEST version of a video game cheat code? (Any reason I shouldn't use these ScrollChlr curves?)

Thanks,
Bill

[cid:image001.png at 01CD173D.066245C0]

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Bill,

If you have the time, why don't you get the vendor rep send you over some data which you can make into curves? See the attached docs if you have not already used/have them.

Steven Gates created the word doc and Jeremy McClanathan the excel spreadsheet.

I would not trust those curves unless someone on the eQUEST development team can validate them.

Tim.

Timothy Howe, MS, LEED? AP BD+C

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Great idea in theory, but good luck getting that much data from a vendor. Also, I don't think there is a development team anymore, they all work on E+ now.

I was just looking at this today, I had a job with scroll chillers. Just at a glance I noticed the EIR =f(PLR) curve is a lot more linear than the screw chiller curve. The limited part load data I had for my chiller seemed to suggest it was a lot more non linear. So your mileage may vary. Also make sure that you normalize any curves that you use to your design EIR. The default curve is EIR2(1) = .1305 .

Elechour = Caphour * EIR * EIR1f(t1,t2) * EIR2f(PLR) / 3413 Btu/kW

So if you don't normalize it is going to think it's using a fraction of the energy that it should be.

Brendan Hall, M.Sc., LEED AP BD+C

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