21-year-old O'Connor has been looking to move away from Crewe after a few spats with Icelandic manager Gudjon Thordarson. O'Connor's attitude and professionalism had come under the spot light with the Iceman and as a result the Irish International was loaned out to Lincoln City.
Last month Irons boss Neil Adkins told the local press that he was interested in singing the Northern Ireland international.
Belfast born O'Connor has been at the club since a kid and had progressed through the academy and impressing in the centre of midfield.
No doubt the money from the deal will be used by Thordarson to strengthen the squad that has already seen 17 players leave during the summer.