The second option if you have taken the unit out is to take
it round to a glazier who can take it apart, clean up the glass
(condensation eventually leaves marks between the panes),
and reassemble with new seals.


I have successfully repaired double glazing units. Two so far, and
they've stayed clear for nearly a year. I've put the details on
www.peter-scott.org.uk/glazing.html

Peter Scott