Re: Ventilation when using top feeder
Build a vent box and install it above the feeder.
A vent box is simply a "mini super" built from 2X4 and drill two one inch holes in each side, slope the holes downward for rain. 4 inch side is vetical. Cover the holes with 1/8 screen.
Can use 3/4 inch material but I like the 2x4 as with glue and screws, I make a simple butt joint. Very easy and strong corner to build.
With a wind and air flowing through the vent box, should get a venturi effect and actually "suck" air upwards through the hive.
Check D E Hives where they promote good ventilation to increase honey production.
If you always do what you always did, you'll always get what you always got!