Heat Exchanger, Fre SVCE (511, 550)
  511     Use Prior to Serial #964470.
          Use From Serial #964770 to #1004774.
          From #964470 to #964769 Use 7016591.
          From #1004775 to #1204689 Use 7016591.
          Starting With #1204690 Use 7016527.
  550     Use From M681166/P612941 to M/P964069.
          Use From #964470 to #984749.
          Use From #985150 to #1004774.
          See 7016107 For Additional Serial Breaks