Three of the black wires are pigtailed to one of the white wires. All the grounds are connected together. This leaves 3 white wires that were together and a single black wire.
I did not take a picture but thought old fixture had white wire connected to 3 other white wires and black wire connected to single black wire, leaving the set of 3 black and single white pigtailed as was.
When I connect my blue and black fan wire to single black and white fan wire to 3 white wires (and ground to ground) fan does not work and circuit trips in breaker box.
Any thoughts on what I am doing wrong or need to test (if I need to go and get a meter to do some testing).
Any help is much appreciated.