:lau
my incubator has a fan and 3 tiny holes on the bottom of the door. I open it every day and spray/mist the eggs that are in lockdown. the eggs that do not hatch usually are infertile. very few dead in shell (mostly shipped eggs).
do you have any storage room or any cooler part of the house? 18 C should be ideal, 20 C ok, but I wouldn't keep the eggs on 22 C for long. 40% humidity is ok.