Loop to Loop Heat Pump EIR - SPECIFIED-AT?

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Hello all,

When defining a Loop to Loop heat pump, there are no entries enabled for the temperatures at which the EIR applies. Can these temperatures be found anywhere in the generated files or does anyone happen to know what they are? Also, is it possible to add SPECIFIED-AT keywords in the INP for loop to loop heat pumps?

And lastly, which hourly reports would I need to generate to see what my performance looks like over the year? I'm looking at a variety of them and some things aren't what I am expecting so if someone could share, it would be much appreciated.


Riley Beise, P.Eng., BEMP, LEED Green Associate

Riley Beise2's picture
Joined: 2013-02-14
Reputation: 200


The DOE2 help topic for "Loop-to-Loop Heat-Pump" mentions (at the very bottom) that "the performance curves are normalized at the Eurovent rating conditions". I don't know what a Eurovent is - is that like the Chunnel? You can always plot out the performance curves to verify where they are normalized by determining the independent values (CHW and HWR temperatures) needed to get the dependent value to be equal to "1.0".


[Senior Energy Engineer 28Jun2012]

Bill Bishop's picture
Joined: 2012-02-25
Reputation: 7

Bill, thanks for the response. Eurovent = Chunnel. I had a bit of a chuckle at that.

In other news, now that I have had some time to get back to this project, I am happy to report that manually entering the SPECIFIED-AT code in the INP manually appears to work as expected. I suppose eQUEST just doesn't include those input fields for loop-to-loop heat pumps, but DOE will use them if you enter them. I can't speak to whether or not the default loop-to-loop heat pump curves are appropriate for my equipment, but given the limited information we routinely receive, I think that they will have to do.

To summarize, I was trying to enter the specific conditions that my heat pump was rated at to ensure that the heat pump plant's performance adjusted appropriately for loop temperature resets and part load operation. Unfortunately with a loop-to-loop heat pump, eQUEST does not allow you to specify the conditions at which it is rated. Fortunately however, it appears that you can enter the appropriate code manually in the INP file and get your heat curves normalized to the right temperatures, rather than the default "Eurovent" conditions, which I was unable to find (in 5 minutes on the Eurovent website).

Specifically, I added three lines (DESIGN-CHW-T, DESIGN-COND-T, and SPECIFIED-AT):

CAPACITY = 0.150574
CHW-LOOP = "Chilled Water Loop"
CHW-PUMP = "P-14"
CHW-DT = 5.1
HW-LOOP = "Hot Water Loop"
HW-PUMP = "P-13"
CW-LOOP = "Ground Source Water Loop"

If anyone sees a problem with this method, please let me know.

Riley Beise, P.Eng., BEMP, LEED Green Associate

Riley Beise2's picture
Joined: 2013-02-14
Reputation: 200