There could be several reasons why air conditioner keeps blowing fuse in circuit board.
Furnace control board 3a fuse blowing.
The most probable of these are 1.
Loose electrical cables there could be loose electrical cables inside the circuit box or somewhere in your ac which could be causing a short circuit.
2 reconnect all wires previously disconnect at control board.
This will blow the fuse on the control board causing the draft inducer to not start which then stops the rest of the furnace functions from working properly.
I know there is a short somewhere and i ve read on multiple posts to remove the wires from the 24 volt terminal block w r g c y and start putting them back one by one until the fuse blows again and then you ll find your problem.
The 3a fuse had blown again.
Go to outdoor unit.