I'm sure you're right, but that's not what irritates me.  I was having
other A/C problems late this winter (January or so).  Sometimes the
blower would come on, sometimes it wouldn't.  I'd spin the knob hoping
to hit a sweet spot and make it turn on.  Sometimes it worked, usually
it didn't.  I replaced that control unit, thinking maybe the knob pot
was bad.  Anyway, that wasn't the issue.

So I took it in to the dealer.  He told me the system was "over
charged" so they released some coolant.  I don't recall having my
system serviced, but let it go...

So he must have taken the coolant out, and maybe that wasn't the
issue...

So... while the blower usually turns on and spins at the speed I
desire, we're just blowing warm and semi-cold now.  I'll have it
looked at for more coolant to be added.  Thank you.