If you have not filed, simply go back into the return and change the bank account number before you file.
If you have already filed,:
- most likely, it is too late to do anything except wait for the bank to reject it
- if it is routing to the correct bank, you can try proving to the manager what happened and you may get your refund. A small bank in a small town has more room for things like that.
Once the bank rejects it, the IRS will mail a paper check to your address.