We have been getting the F97 error code for the last year. I could get the oven to work for a period of time by using my shop vac to clean and spin the lower fan, but eventually even that wouldn't work. My guess was that the lower fan or the board sensor was bad, so my plan was to replace both. Pulling the oven was fairly straight forward. Four screws at the front, and it slides right out. I removed both doors and all the racks to reduce weight. But be aware that the oven will not function with the doors removed, so you will need to replace them to test your work. I used a workout/weight bench to set the oven on (just happened to be the perfect height). Several overlapping sheet metal panels needed removed, but access to the lower fan was fairly easy. One big red connecting clip to disconnect and the whole fan and wire harness comes right out. I needed to borrow two nuts from the old fan to attach the new board sensor to the new fan. I would recommend taking a few pics as you go to remind you of the correct reassembly sequence. Overall the hardest part was getting the oven back in the cabinet. Ours was a replacement oven, and barely fit in the cabinet to begin with. Kept hitting the power cable and would not seat all the way back. After about 10 attempts, I was able to get it "good enough". My wife was able to bake cookies for the first time in 3 weeks.