If you have bats in your chimney, and not in any other part of the house or attic, the situation is a little easier, because the bats are confined to one small area. Before discussing bat removal tactics, there are two very important things to keep in mind!
MAKE SURE THE DAMPER IS SHUT – So that bats don’t get into the house and start flying around once you do your bat exclusion.
DO NOT START A FIRE – You will have to open the damper to start a fire, and when you do, bats will get inside the house. If you start a fire, for some reason many bats crawl down and fly out the bottom rather than the top. Plus, many bats would die, and to kill bats is illegal and inhumane. Plus, bats can fit through very small areas, and you may find bats in the attic and walls if you start a fire.