Description of Chiller EIRFPLR in I/O Reference

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The nature of EIR is power (W) / cooling capacity (W), so I'm confident that the I/O Reference is correct. You might check the definition of EIR to gain confidence about this.

I know the definition of EIR. The problem is that this curve does not represent EIR. I think the curve name should be changed to avoid confusion. In this paper, @rraustad explains Cooling Energy Input Ratio Modifier Function of Part-Load Ratio Curve. He says that "The name of this curve is somewhat misleading in that this curve is a ratio of operating power to rated power". Although this paper is for VRF performance curves, I think the same is true of the chiller performance curve.

The curve in question:

this->ChillerEIRFPLR = Curve::CurveValue(state, this->ChillerEIRFPLRIndex, PartLoadRat);

with

this->Power = (AvailChillerCap / ReferenceCOP) * this->ChillerEIRFPLR * this->ChillerEIRFT * FRAC;

So EIRFPLR needs to provide the fraction of full load power at operating PLR.

Note that FRAC represents the chiller cycling on and off, not the fraction of full load power.