I am learning a lot by slowly taking apart my Boler
. Today's lesson: how to install a fan vent to ensure the maximum amount of water leakage.
1. Remove original fan
2. Glob silicone in the 40 or so screw holes
3. Drill 40 or so new screw holes
4. Attach the fan with 15 screws
5. Glob silicone around underneath the base
6. Glob white caulk around the outer rim
Now sit back and imagine the delighted surprise of the owner who several years later discovers the 80 (seriously! 80!) leaking screw holes in the ceiling.