Hi Ramzes,
To understand your question I turned on "Record Macro" and clicked on a pivot table. I got two lines of code:
    ActiveSheet.PivotTables("PivotTable1").PivotCache.Refresh
    ActiveWorkbook.RefreshAll
I don't see any RefreshSheet word in the Object Model.

My normal method to understand these kinds of questions is to record a macro and then see how I might modify it to work in general.

hope this helps.