I recently had the same thing occur.  I was trying to get my propane tank
filled just before the New Year in preparation for Y2K problems.  It was very
cold here,
-15C, in Almonte, Ontario.  When service attendant tried to get his fill
nozzle released he could not.  Propane was escaping and the whole thing froze
up.  Finally with the help of some thick rubber gloves and a large pair of
channel locks he was able to get it free.  This had never happened before and
I didn't think much more about it until this latest posting.  I suppose there
could very well be a problem with auto shut off valve sticking or freezing up
in very cold temperatures.  I will be going back to the same place for a
refill sometime soon when the temperature gets above freezing to try and fill
the tank again.  Then we will see what happens.  I read David's posting about
releasing the relief valve on the fill nozzle but I don't recall there being
one on the fill nozzle being used in this instance. I will check into this
when I go back for the refill.  More news later.

Cheers

Frank Condelli
'87 Westy & Lionel Trains
Almonte, On
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