There are different reasons why it might act like that depending on the control system.
However if not enough air flows, Even though it's enough to trip the sail switch, This can be due to obstructions IN the flues (very common, dirt collects there) or due to stuff on top of a register (I'm still trying to educate my wife) the unit will over heat, and shut off, then cool down exactly as you describe.
A defective Overheat safety stat can do it too.
There may be other causes as well. If it's running at least 5 minutes before shutting down I do not ***THINK**** it is the control board (my problem is the control board, it runs for seven seconds as I recall)
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