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PRM: PSZ-AC Cooling curve out of bound #80

Open jmarrec opened 8 years ago

jmarrec commented 8 years ago

I'm getting warnings for all my PSZ-AC DX cooling coils. Here it is for one of them, with DisplayExtraWarnings

** Warning ** SizeDXCoil Coil:Cooling:DX:SingleSpeed ZONE1 PSZ-AC 1SPD DX AC CLG COIL 24KBTU/HR 13.0SEER
**   ~~~   ** ...Gross Rated Total Cooling Capacity [W] will be limited by the minimum rated volume flow per rated total capacity ratio.
**   ~~~   ** ...DX coil volume flow rate (m3/s ) = 0.277777
**   ~~~   ** ...Requested capacity (W ) = 8774.387
**   ~~~   ** ...Requested flow/capacity ratio (m3/s/W ) = 3.165E-005
**   ~~~   ** ...Minimum flow/capacity ratio (m3/s/W ) = 4.027E-005
**   ~~~   ** ...Adjusted capacity ( W ) = 6897.883
** Warning ** The Standard Ratings is calculated for Coil:Cooling:DX:SingleSpeed = ZONE1 PSZ-AC 1SPD DX AC CLG COIL 24KBTU/HR 13.0SEER but not at the AHRI test condition due to curve out of bound.
**   ~~~   **  Review the Standard Ratings calculations in the Engineering Reference for this coil type. Also, use Output:Diagnostics, DisplayExtraWarnings for further guidance.
**   ~~~   ** CheckCurveLimitsForStandardRatings: The max and/or min limits specified in the corresponding curve objects
**   ~~~   **  do not include the AHRI test conditions required to calculate one or more of the Standard Rating values.
**   ~~~   ** Coil:Cooling:DX:SingleSpeed=ZONE1 PSZ-AC 1SPD DX AC CLG COIL 24KBTU/HR 13.0SEER:  Seasonal Energy Efficiency Ratio (SEER) calculated is not at the AHRI test condition.
**   ~~~   **  Check limits in Part Load Fraction Correlation Curve, Curve Type = CUBIC, Curve Name = COILCLGDXEIRRATIO_FQFRAC 4
**   ~~~   ** Coil:Cooling:DX:SingleSpeed=ZONE1 PSZ-AC 1SPD DX AC CLG COIL 24KBTU/HR 13.0SEER:  Integrated Energy Efficiency Ratio (IEER) calculated is not at the AHRI test condition.
**   ~~~   **  Check limits in Total Cooling Capacity Function of Temperature Curve, Curve Type = BIQUADRATIC, Curve Name = COILCLGDXQRATIO_FTWBTOADBSI 8
**   ~~~   **  Check limits in EIR Function of Temperature Curve, Curve Type = BIQUADRATIC, Curve Name = COILCLGDXEIRRATIO_FTWBTOADBSI 8
jmarrec commented 8 years ago

COILCLGDXEIRRATIO_FQFRAC 4:

OS:Curve:Cubic,
  {7c8d6332-fb37-45c9-8770-c8bbda9f5059}, !- Handle
  CoilClgDXEIRRatio_fQFrac 4,             !- Name
  0,                                      !- Coefficient1 Constant
  5.1091,                                 !- Coefficient2 x
  -8.5515,                                !- Coefficient3 x**2
  4.4744,                                 !- Coefficient4 x**3
  0.7,                                    !- Minimum Value of x
  1,                                      !- Maximum Value of x
  0.92,                                   !- Minimum Curve Output
  1;                                      !- Maximum Curve Output

COILCLGDXEIRRATIO_FTWBTOADBSI 8:

OS:Curve:Biquadratic,
  {da84fd1f-6c75-4b7c-8086-9f934f59708c}, !- Handle
  CoilClgDXEIRRatio_fTwbToadbSI 8,        !- Name
  0.116709,                               !- Coefficient1 Constant
  0.028458,                               !- Coefficient2 x
  -0.000411,                              !- Coefficient3 x**2
  0.021422,                               !- Coefficient4 y
  0.000162,                               !- Coefficient5 y**2
  -0.00068,                               !- Coefficient6 x*y
  13.89,                                  !- Minimum Value of x
  25,                                     !- Maximum Value of x
  23.89,                                  !- Minimum Value of y
  46.11,                                  !- Maximum Value of y
  0.77,                                   !- Minimum Curve Output
  1.33;                                   !- Maximum Curve Output
jmarrec commented 8 years ago

https://github.com/NREL/EnergyPlus/blob/8280b7e5e1d2ed7a1b0beae2a916669d15039dde/src/EnergyPlus/StandardRatings.cc#L2424

mdahlhausen commented 2 weeks ago

Note: both of these curves come from From CBECC Appendix_3.7_PerformanceCurves-S901G.xlsx CBECC has since adopted newer curves for different kinds of equipment. Consider updating curves as part of the curve refactoring.

jmarrec commented 2 weeks ago

For the record, I do appreciate getting input on an issue reported 8 years ago! Thanks for scanning old issues, I know it's tedious and annoying but helpful (to bump or close)!