We just recently bought a foreclosed home and have completed a ton of work on the house. Because of the sanding, cleaning, etc, there is a ton of dust and debris down in the vents. We are having a CO2 test performed tomorrow and my question is, during this test will the air be blowing up into the vents? I tried to vacuum the vents out but I can only get so far. I am supposed to have the vents cleaned next week, so should I wait until after that to have the CO2 test done? I know nothing about this sort of thing, so much info is appreciated. Thanks!