## Tips and Tricks for Using EnergyPlus — EnergyPlus 8.8

### Tips and Tricks for Using EnergyPlus

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 %