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If you set the reporting frequency of your output variables to 'Detailed' you will see that there is actually not simultaneous heating and cooling, that heating occurs at the end of the night temperature setback to raise the temperature to the daytime heating set point, and cooling occurs when the zone temperature is right at the daytime cooling set point. This is how I would expect this system to operate.

Reporting the variables hourly will obscure how the system is actually performing, since HVAC systems are simulated at sub-hourly time steps.

If you set the reporting frequency of your output variables to 'Detailed' you will see that there is actually not simultaneous heating and cooling, cooling; that heating occurs at the end of the night temperature setback to raise the temperature to the daytime heating set point, and cooling occurs when the zone temperature is right at the daytime cooling set point. point to maintain that temperature. This is how I would expect this system to operate.

Reporting the variables hourly will obscure how the system is actually performing, since HVAC systems are simulated at sub-hourly time steps.

If you set the reporting frequency of your output variables to 'Detailed' you will see that there is actually not simultaneous heating and cooling; that heating occurs at the end of the night temperature setback to raise the temperature to the daytime heating set point, and cooling occurs when the zone temperature is right at the daytime cooling set point to maintain that temperature. This is how I would expect this system to operate.

Reporting the variables hourly will obscure how the system is actually performing, since HVAC systems are simulated at sub-hourly time steps.

If you set the reporting frequency of your output variables to 'Detailed' you will see that there is actually not simultaneous heating and cooling; that heating occurs at the end of the night temperature setback to raise the temperature to the daytime heating set point, and cooling occurs when the zone temperature is right at the daytime cooling set point to maintain that temperature. This is how I would expect this system to operate.

Reporting the variables hourly will obscure how the system is actually performing, since HVAC systems are simulated at sub-hourly time steps.

Here is a plot from your model with variables reported hourly:

Here's the same plot with variables reported at Detailed frequency:

And here it is at detailed frequency with 6 time steps per hour:

If you require the system to be off at night no matter what, you should apply an availability schedule. In OpenStudio this can be done in the Air Loop control view (see here).

If you set the reporting frequency of your output variables to 'Detailed' you will see that there is actually not simultaneous heating and cooling; that heating occurs at the end of the night temperature setback to raise the temperature to the daytime heating set point, and cooling occurs when the zone temperature is right at the daytime cooling set point to maintain that temperature. This is how I would expect this system to operate.

Reporting the variables hourly will obscure how the system is actually performing, since HVAC systems are simulated at sub-hourly time steps.

Here is a plot from your model with variables reported hourly:

Here's the same plot with variables reported at Detailed frequency:

And here it is at detailed frequency with 6 time steps per hour:

If you require the system to be off at night no matter what, you should apply an availability schedule. In OpenStudio this can be done in the Air Loop control view (see here).

For how air system control is simulated in EnergyPlus, see here