Ever since the discussion regarding one the IVPT accidents there is something that I am unclear on... I'm hoping someone can help educate me.  There was mention of a solenoid valve, apparently in the vent system.  Exactly where in the system is it and what is its purposea and function?  (This regards the fuel system that Lancair sells, not the DieMech system.)  TIA for your input.

  <marv>