You blew a fuse.  When it gets colder it will make that blower motor just a
little harder to turn over, which can give you a higher current for just a
few seconds and blow the fuse.  I had this happen on my old Blue '85 and it
only happened once.  The fan needed to be replaced, but the van went to
Vanagon heaven before that even came to pass.

Thanks,
Ken Wilford
John 3:16
www.vanagain.com
Phone: (856)-765-1583
Fax: (856)-327-2242