Woke up this morning to a cold house with the blower motor running on the Lennox G23 furnace. Turned the digital thermostat to the off position and the blower still ran. Not sure if the thermostat turned "off". I forgot to listen for the click of the contact. Then turned the thermostat backed on. Went to the basement and removed upper access panel. The blower was running and the burners were not on. I turned the 120V switched off to the unit and the unit shut down. I waited a couple of minutes and turned the switch back on. As soon as I turned the switch on the blower started.
What could the problem be? Could it be a problem with the blower control board? What fixes could be performed?