I set the thermostat to heat as usual and the furnace does come on and ignites then
Quickly turns off. Only the blower continues to run.
The furnace is only 10 years old.

Most common problem for this is the flame sensor is not sensing the flame , the flame sensor is a small rod with a wire attached to it and sticking into the flame of the burner, remove this rod and sand it litely to remove any corrosion and reinstall. Good luck, Mike