Brian,
That relay under the driver's seat is the refrigerator
shutoff relay. It shuts off the refrigerator (on 12 volt setting)
when the engine is not running, so that the main driving
 battery is not drained.
If you would like to see info for installing a second battery,
 using a dual battery relay or isolator, 
you can check out my website: 
http://www.geocities.com/harald_nancy/
Click on auxiliary battery, there are lots of photos.
It is important that the aux. battery is recharged
efficiently, otherwise the battery won't last very long.
Harald 
'90 westy
----- Original Message ----- 
  From: Brian Wawzonek 
  To: vanagon@GERRY.VANAGON.COM 
  Sent: Thursday, May 10, 2001 2:18 PM
  Subject: 2nd Battery Time Again...

  Wanting to add the second battery to my Westy, I checked postings in the archive, and found that I have the 1"x1" regulator to hook up to under the drivers seat. Next, what battery to buy? Deep cycle sounds most appealing, but the local autoshop says that a deep cycle battery needs lots of ventilation. I don't have any! He also questioned the use of the deep cycle, if the system wasn't set up for it. His concern that the deep cycle will charge too fast, wearing it out prematurely. Would a regular battery be best suited, as far a size and need for our half dozen camps per year. HELP. Thanks as always
  Brian Waz

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