This is a replacement burner head designed for 89 Series and AFL Series Furnaces. This burner has no deflector and larger port holes due to the higher BTU's of the furnaces it's installed on.

The different models and/or BTU ranges of furnaces use different burner heads. These burners differ by the size of the top gas port holes or the deflector that runs through the throat of the burner. If the wrong one is used, it may cause an ignition, sooting or flame sense problem.