Nibal,
You should be able to place the caps onto their own unique layer, freeze that layer, and run your schedule again.

That's supper..
It worked..
but am wondering then I need to freeze the layer each time I'll generate the valve schedule..

Thank you so much..

Nibal

If you want to regen a schedule and the layer is still frozen, then nothing needs to be done. Toggling the layer on or off will show or not show your caps. If you place a new cap, that layer should automatically turn back on.
I suggest doing your design, then when you are ready to run your schedules, freeze the layer, then run your schedules.