Unit does not light. The led is on but not flashing. The fan is not on either.

You need to get up close to watch exactly what is going on, with the top door off check out the sequence/order of what is happening. On start up,1st. The inducer motor should start up,2nd. The igniter should light up, 3rd. The gas valve opens up and the burners fire up,4th. After a minute to 90 seconds the blower should start up. The 2nd-3rd-4th will not happen without the 1st,, the 2nd doesn`t happen without the 1st,, ETC,, check it out up close and personal,, Let us kmow so we can help