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Psychrometric Errors

EnergyPlus has built-in psychrometric routines that perform various calculations for the simulation modules. They typically fall into the recurring error category but may warrant some view:

   ** Warning ** Calculated Relative Humidity out of range (PsyRhFnTdbWPb)
   **   ~~~   **  Routine = NodeReportingCalc:NODE_1, Environment = CHICAGO_IL_USA ANNUAL COOLING 1% DESIGN CONDITIONS DB/MCWB, at Simulation time = 07/21 00:00 - 00:10
   **   ~~~   **  Dry-Bulb = 13.00 Humidity Ratio = 1.000E-002 Calculated Relative Humidity [%] = 104.65
   **   ~~~   ** Relative Humidity being reset to 100.0%

This warning notes that the calculated relative humidity is out of rage (routine name: PsyRhFnTdbWPb). It happened during routine NodeReportingCalc for NODE_1 at the environment "CHICAGO_IL_USA ANNUAL COOLING 1% DESIGN CONDITIONS DB/MCWB" during the time interval 00:00 -- 00:10 on July 21. The dry bulb temperature was 13 C, the humidity ratio was .001 for a calculated relative humidity of 104.65%. It is reset to 100%.

Then, at the end of the run, you will see a summary of how many times that occur and the min/max extent:

   *************  ** Warning ** Calculated Relative Humidity out of range (PsyRhFnTdbWPb)
   *************  **   ~~~   **   This error occurred 645 total times;
   *************  **   ~~~   **   during Warmup 0 times;
   *************  **   ~~~   **   during Sizing 0 times.
   *************  **   ~~~   **   Max = 104.652877 %  Min = 104.652877 %