I have a Frigidaire furnace model # FG6RA 096C-12B. I purchased a humidifier to install and do not have the users guide for the furnace. I need to know which wire is the blower motor common wire. Thanks for all your help.

If there is a white wire running to the blower motor, that is it. If not, connecting to the white wire where the house wiring comes into the furnace should work. All the 120 volt wiring connects to the same common.

There is also a humi connection on the board to make this easier.