Floor vents are needed for keeping homes warm or cool, if you have a forced-air system in your home. But they create openings in the floor that small items can easily be dropped into. Access is not always simple when you need to retrieve the dropped item, but there are a few ways you can attempt to rescue it before giving up.
Remove the vent cover. Most vent covers installed in floors will simply lift off. If it's screwed in place, remove the screws and lift the cover off the floor.
Reach down into the vent as far as you can, and feel for the item. How far you can reach will depend on the sizes of the ductwork, the vent hole and your arm. Carefully grab the item, if you can feel it, and pull it out.
Untwist the top of a wire hanger and partially straighten it, leaving the top hook as is, if you were unable to reach the item. Gently push the hanger down the floor vent, hook-first. Allow the hook to settle against the bottom of the vent, and pull it back toward you until you hear or feel it hook onto the lost item. Keep pulling the hanger back, and grab the item with your free hand as soon as it becomes visible. If the hanger does not catch the lost item, reinsert it and let the hook settle in a different area of the vent before pulling it back up.
Turn on the vacuum, and slowly push the hose down the vent hole until it can't reach any further. Pull the hose back out of the vent, and turn off the vacuum. Remove the vacuum's canister or bag, and look inside to see if the lost item was suctioned up.
Disassemble the duct work below the vent, if you can access it. Remove the duct and tip it downward until the item falls out.
Hire a duct cleaning company, if you have been unable to remove the item yourself. Their large suction systems, used to remove dust and debris, are likely to be strong enough to dislodge and suction out whatever you lost.