Example files 5ZoneVAV-ChilledWaterStorage-Mixed primary chiller is always off

edit

On analysis of the simulation results of the example file with storage '5ZoneVAV-ChilledWaterStorage-Mixed', I found between June to November that the primary chiller is always at 0 for electric power, cooling demand rate. However, the outlet temperature at the outlet node is=setpoint 7.5 C. As this is the storage charging loop, This should not happen. What could be wrong with the controls in this example file?