Some good info that I recently found abt pepper fruit set...
http://aces.nmsu.edu/pubs/_h/h-230.pdf
Fruits do not set when mean temperatures are below
60oF or above 90oF. However, flowers drop when night
temperatures are above 75oF. Fruit set may be stalled if
temperatures rise above 90oF after several flowers have set
and fruits are developing. This causes a split in the fruit
setting continuum and is called a split-set.
http://aces.nmsu.edu/pubs/_h/h-230.pdf