After the flame is shut off it take about 2 - 5 minutes for the fan to shut off. That is to remove as much heat as possible from the unit. Could this be your case?
If it is running past 5 minutes it is probably the electronic control board in the furnace.
Chuck - Sparta, TN
2012 Jay Flight 22FB, 2 x Honda EU2000i
2013 GMC Yukon XL Denali AWD
EDUCATION is what you get when you read the fine print.....
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