I want to thank the various 'listees' who helped me solve the electrical
problem on my '90 Westfalia.  Especially Harald@earthlink who went to
the trouble to open up his a/c electrical panel and give me normal
current readings for a properly operating system. Almost above and
beyond the call of duty!
The problem and the solution are as follow:  The main a/c fuse, fifty
amp bar type, blew.  The a/c mechanic, not VW type, replaced it with a
50 amp circuit breaker.  The breaker would open on speeds 3 and 4 after
a few minutes of operation.  The a/c mechanic was fairly sure that the
problem was the radiator fan but I was not $500 convinced.
I noticed that the wire terminals seemed to get hot very quickly so I
installed heavy duty wire terminals on the wire ends to reduce the IR
drop.  The system would now operate on speeds 1,2, & 3 without tripping
the breaker.  Harald and I compared the current readings on our
identical a/c systems and determined that the currents were nearly the
same, mine slightly higher as determined by a meter of unknown
accuracy.  The system draws almost 50 amps on speed 4 with the
compressor running, Very questionable design IMHO!  I replaced the relay
with a fuse of the original type, a VW fuse, and the system now hold ok
on speed 4.  The fuse gets very, very hot but does not open.  I get good
cooling on speed 3 so I have decided to leave it this way but to avoid
speed 4 like the plague as I don't like to run things that close.
Life with a vanagon is made much easier by having a group like you
available to help.
Gordon Bonham
Now---'90 Westfalia
Then---'82 Diesel Westfalia
Before Then---'73 Westfalia