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# Chiller curve and AHRI test condition.

Hi

It looks like the IPLV calculated for my chiller is not at AHRI test conditions,

** Warning ** Chiller:Electric:EIR = CHILLER ELECTRIC EIR 1:  Integrated Part Load Value (IPLV) calculated is not at the AHRI test condition.
**   ~~~   **  Check limits in Cooling Capacity Function of Temperature Curve, Curve Type = BIQUADRATIC, Curve Name = CURVE BIQUADRATIC 47
**   ~~~   **  Check limits in EIR Function of Temperature Curve, Curve Type = BIQUADRATIC, Curve Name = CURVE BIQUADRATIC 48


Is there a work around for this issue or should I change my chiller ?

TABLE 3

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This is just a warning to tell you that the min/max values for X/Y variables exceeds the limits defined from AHRI 551/591,2011 Table3. These limits are defined in StandardRatings.cc#L704:L70. You'll see in the next 80 lines after that, that all it does is to compare your Curve Min/Max X/Y with these values (and depending whether your chiller is air cooled or water cooled).

So double check these limits are whether your curve as a whole is appropriate and if so, then ignore the warning.

A common cause for this warning may be that you use an Aircooled curve for a Watercooled chiller or vice versa... Not sure what your chiller is supposed to be here.

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My chiller is a water cooled chiller. I changed the Xmin, Xmax to 7, Ymin and Ymax values to 19 and 30 but still the error persists. I checked the AHRI 551/591 it gives those values. I have attached a picture of that table 3 above. Could you please help me regarding this issue ?

( 2018-09-27 07:46:04 -0500 )edit

Xmin and Xmax shouldn't be both 7. Read the description here. "The biquadratic curve should be valid for the range of water temperatures anticipated for the simulation"

( 2018-10-02 02:32:28 -0500 )edit