What are these types of burners called?

It’s a top feed, with the oil nozzle & sparkers on top, and fan feeding in through the bottom.

Any ideas?

As far as I know they are referred to as Vertical Burner (upright) as opposed to a Horizontal Burner.

From my understanding the upright Vertical Burners are the better choice.

Yup. but I was thinking there might be a sub category of sorts for this type of burner. It is a vertical, but as I said, the oil goes into the top, and then fan into the bottom. Not a typical vertical with a Beckett burner where everything goes into the bottom. This is a split unit so not every type of pump/fan combo can be used with it.