The fan probably operated on the heat... I would tackle the THERMOSTATS
, heat elements (at least 2) and/or fuse first.
My favorite supplier, appliancepartspros, struck out on Breville
(never-mind) I'll add a couple of credible ones at the bottom.
Sears parts is a good information source... but very pricey ($$$$) for the EXACT SAME PARTS you can get elsewhere...
If you can determine from your OWNERS papers which part you want to try first... get the operating parameters... and and check with a volt meter (ohms scale... power OFF)... for continuity on the FUSE, heaters & thermostat.
There is a possibility your control board (PCB) is at fault... it seems to be getting scarce... Turn it over and look for a burned/broken solder joint.
In any case... get three prices...
In the event that PCB is the issue I do recommend LOOKING TO SEARS because of their parts support and warranty...
Good luck (finding the FUSE).
Breville BOV800XL Smart Oven Parts
Parts and Accessories
Sears Appliance Parts