Putting them in the fridge is a bad thing if you are setting the eggs before they are 14 days old. If you are keeping them over 14 days it helps. You would want to let them warm up a hour or three before putting them in the incubator.
To get the most out of one hen an one incubation....
For the first two weeks you want to take each egg as you collect it an put it in the incubator for 6 hours. After that 6 hours take it out put it in the fridge. After that 2 weeks collect another 2 weeks worth of eggs the same way but dont...