Range.SpecialCells() method to get a reference to the cells containing formula errors and then delete them.
[pre]Sub foo()
Dim rngToCheck As Range, rngToDelete As Range
Application.ScreenUpdating = False
'change Sheet1 to the codename of the sheet you want to check
With Sheet1
Set rngToCheck = .Range(.Cells(6, "O"), .Cells(500, "U"))
'if there are no error cells then there will be an error
On Error Resume Next
Set rngToDelete = rngToCheck.SpecialCells(xlCellTypeFormulas, xlErrors)
On Error GoTo 0
'allow for overlapping ranges
If Not rngToDelete Is Nothing Then _
Intersect(.Range("A:A"), rngToDelete.EntireRow).EntireRow.Delete
End With
Application.ScreenUpdating = True
End Sub