Paul,

Yes, you will need to remove the unit from the counter.

You may raise and support the unit with coverred boards high enough to access the cooktop frame perimeter screws, if you prefer,and lift the cooktop off the burner box to access the fan switch. I presume you know you will need to remove everything off the cooktop(vent cover,grates,etc.)before you start to remove the unit .

Use extreme caution with the glass cooktop when removing or off, it is temperred glass and could shatter.

Thanks for contacting appliancepartspro/ repair forum