1

Turn OFF furnace power

2

Take a photo of the circuit board with all its wiring connections

Remove all wiring from circuit board

3

Replace circuit board

Please refer to the photo to re-connect all wiring

4

Put bottom cover back on furnace

Make sure that it is tight and in correct position

5

Turn ON furnace power

6

​Go to Thermostat, make sure system is "ON", "Heat", Fan is "Auto"

Wait a few minutes, the furnace will go through firing sequence, and warm air should come out from registers once the sequence is successful