Cooling demand per hour only for one zone

Does anyone know why the cooling demand per hour only shows if you do a single-zone model?

I am using @chris script Visualize Peak Loads for HVAC.

See below the difference between one and more zones:
-for this model, I have six zones. The cooling demand is a single value.

-on this model, I have one zone. The cooling demand is per hour:

Regards, (741.4 KB)