got a code F1. I turned off the power for 5 minutes to see if that would reset. It didn't. So I think I need to replace the circuit board. Or should I buy a new dryer?

You would be correct you do need to replace the dryer control board. If you would like the part information for your model open a new question and give me the full model number of the dryer. The model number is located on a tag on the frame of the dryer behind the dryer door. Open the door and you will see a tag with the model and serial number on the frame.