Hi Paul (and others with a whistling sound from the heater),
The whistling sound coming from the heater in my van started about the
same time that a three-inch strip of black insulating material fell out
of the heater vent. The only time it doesn't whistle is when I open the
vent about half way. I'll just bet that if I replace the insulation, the
whistling will stop. Any comments about doing that from others will be
greatly appreciated.

P.S. What a great help this list has been in helping us take care of our
"Adventuremobile"

Lee & Irasema Kouns
88 Westy
Downey CA