Do Not Turn The Furnace On Until You Have Aired the Van Out For At Least 2 Days . if you have a good sized Fan or a Leaf Blower I would Open All Doors and Blow your Van Out from Several Different Directions . Wait at least 1 More Day and check again for any Propane Odors , Make Sure To Open All Compartments when Blowing and Sniff Checking . Propane is Heavier than Air and Will Seek Out the Lowest Area's In Your Van , so Get Your Nose or Leak Tool As Low As Possible to the Floor ! You should even Lower your Head Into All Accessible Compartments and Check Them .