I have the following "strange" situation: If I am running a normal 1zone simulation in EnergyPlus, the Zone AirTemperature is between 6,5 and 7°C for a day in January. If I am adding "OutputDiagnostics:ReportDuringWarmup" ( otherwise all the same), the Zone Air Temperature is between 21 and 22°C. Does anyone have an idea?
At the beginning of each new environment (RunPeriod or SizingPeriod), all surface and zone temperatures are initialized to 23.0C, and then the first day of the environment is repeated to establish the temperature history in the surfaces. When two successive days result in loads and temperatures within the specified convergence tolerances, then warmup is complete, and the simulation proceeds through the rest of the days in the environment. (See Input Output Reference, Building object for more information).
When ReportDuringWarmup is active, the time series output will repeat for each warmup day. If you go to the last repeat of the first day it will match the same day as reported without ReportDuringWarmup.
For example, if the RunPeriod starts on January 1, then the output for January 1 will repeat several times before January 2 is reported. The last set of January 1 results will match the results for January 1 when ReportDuringWarmup is off.
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