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[EnergyPlus_Support] Chiller model Reformulated EIR

I am using an energy plus model with a chiller using the reformulated EIR model. Results are outputted on a minutely basis. I am trying to reproduce some of the calculations because it is not behaving as expected. The model has three functions:

EIRFPLR = EIR as a function of part load ratio
EIRFTemp = EIR as a function of the cond, chilled water temperatures leaving the chiller.
CapFTemp = Capacity as a function of part load ratio.

I am tracking these three function outputs as well as the COP minutely with outputs. I have varified the three above function outputs and get them to match. (Although energy plus does not used the adjusted capacity when calculating the PLR that is input to the EIRFPLR function. I have seen it the other way in literature as well, but the difference is fairly small).

My questions is "Given that we have EIRFPLR EIRFTemp and CapFTemp how should one calculate the chiller COP?" 
Based on my understanding of the Reformulated EIR calculation the correct calculation should be...

(Design COP)/(EIRFTemp * EIRFPLR)

I do not get this result in energy plus. I am off by more that just a multiplicative factor as I have tested a couple points and the diffence (or ratio) of the expected based on the above equation and the energy plus results changes. They differ by more than 100% A COP of 2.3 offered by energy plus and a COP of 5.8 per the calculations.

Any information about this calculation in energy plus would be appreciated.

Michael



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