Although the call for heat has ended and the burner has turned off there is still heat in the combustion chamber that is re-heating the heat exchanger. If you have the mechanical type fan limit switch then when the temperature gets hot enough the fan switch reactivates and purges the heat out of the system.
Check to make sure your filter is clean, that your vents are open, and that no one has blocked any of them with, maybe, a Christmas tree and gifts.
If the women don't find you handsome, they should at least find you handy!
This post was edited by an admin on December 25, 2013 3:19 PM.
could this be a belt driven model ? how about a picture of the burner or a model or manufacturers name of the burner.
hard to sometimes think just where to start because not all burners are made the same.