[jnaas2]

If you have lived there for a while and this just started to act up its from low air flow across the heat exchanger. When it hits the temperature limit it shuts the burner off until it cools down then will start the burners again. This can be caused by vents being shut to rooms in the attempt to save on heating bills or from a dirty blower wheel or filter. The fan moter has different speeds and the blower speed may need to be changed but first make sure everything is clean and working right first