I have a lennox elite series furnace model number g26Q 3/4-100-2 . Was having problems with it not lighting. So I took the flame sensor out cleaned it put it back together. Fired right up thought all was good. Hour laterI checked it and it was blowing cold air. Only thing running was the furnace blower. So I turned it off tried to restart it, Now when I try to restart it the furnace blower instantly comes on. The combustion blower never runs, I checked for power to the combustion blower and I am not getting anything. Any ideas of where to start with this?