"b-n-d emerson" wrote in message
...
I would still have it looked at. on most forced air gas furnaces, the
fan will not come on until the output temp rises to a factory set temp
and runs after the flame goes out to cool down the heat exchanger.
someone may have "worked on" your furnaces in the past.


As I remember it, the fan came on first from the day they installed it,
about 10 years ago. The only person that has worked on it, in the past, was
the HVAC person servicing it.