Date:         Fri, 8 Sep 2000 08:19:02 +1100
Reply-To:     David Del Ben <ddelben@AIRINTER.COM.AU>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Del Ben <ddelben@AIRINTER.COM.AU>
Organization: Air International Transit
Subject:      Vanagon Air Conditioning
Comments: To: mike miller <mwmiller@cwnet.com>
Content-Type: text/plain; charset="us-ascii"

hhhmmmmmmm
I tend to use a lot of 'filtering' from on the information I read on this
list. There's a lot of really great information, then there's information
that can be at best be described as 'suspect' - then there's some comments
from people that you know are 'old wives tales'.

In my job, I have had a great deal of experience on Condenser Fan
durability on Bus A/C systems. The primary item of wear in DC motors is the
commutator brushes. The main factors affecting brush wear are:
How clean the electrical power suply is
Applied Voltage & current density of brushes
Brush material, design, construction
motor temperature
motor rpm

Motor rpm & temperature are relatively minor factors compared to the
others.
Running the motor on high speed is simply running direct power instead of
through a resistor.
Maybe the Vanagon radiator fans are not designed to be run on high speed
for some reason. I cannot really comment - because I don't know their
specific design.
Though based on my experience - I doubt it.

Also - you will probably get about 3,000 hours life from the brushes - give
or take.
Do some calcs and see how long that will last!!

David Del Ben
85 1.9-Vanagon

-----Original Message-----
From:   mike miller [SMTP:mwmiller@cwnet.com]
Sent:   Thursday, September 07, 2000 4:18 PM
To:     David Del Ben; vanagon@GERRY.VANAGON.COM
Subject:        Re:      Vanagon Air Conditioning

From what I understand from some answers I got on this list running the
radiator fan at high speed when the AC is on is not a viable solution.  My
was wired that way and the AC worked great but the consensus of the list
was
that the radiator high speed fan was not meant to be run continuously and
would burn out.  And it's quite expensive.

I'm going to try and rig an auxiliary fan on the condenser somehow.  Looks
mighty tight in there though.

Mike

----- Original Message -----
From: "David Del Ben" <ddelben@AIRINTER.COM.AU>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, September 06, 2000 6:28 PM
Subject: Vanagon Air Conditioning