While I agree that making sure that the heater valve
is closed is important, it doesn't address the real
problem, air flow through the heater/defroster
distribution box due to bad or leaky seals inside the
box. If you stopped the air flow through the
distribution box, it wouldn't matter whether the
heater valve was open or closed. If the airbox seals
leak and the heater valve is closed, you will still
get outside temperature air into the van.

Here is a simple test. Close all the vents using the
dashboard levers/controls and turn the fan on '4'.
Feel around all the vents to see if you have any
airflow through them. If you can't feel any airflow,
the seals in the distribution box are intact. If you
feel airflow, either pull the dash and air box and
replace the seals, or find a way to stop the airflow
at the vent itself. I use foam rubber blocks and
package wrap plastic.

Sealing the flaps/openings will help the air
conditioned air to get to the front of the van,
especially in a camper. You don't want any outside air
entering the van, after all, that's why you have the
A/C on in the first place, because it's hot outside.

Staying cool on the road in Orlando,

=====
TJ Hannink
Goldibox - 1987 Vanagon Camper, Wolfsburg Edition
Winter Park, Florida
http://home.earthlink.net/~tjhannink/
http://groups.yahoo.com/group/wolfsburg_campers
http://photos.yahoo.com/tjhannink [Vanagon] Album

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