YEP.....if you had operated it on propane then flue could have still been warm from gas flame
On lower control board is a 5A glass fuse.that is for the electric element
Electric element is a 325W (#0173742180). Unplug leads from lower board and test resistance across the leads.......should be 44 ohms
Unplugging electric element from board and plugging it into a 120V AC source is usually a test for whether or not cooling unit is functioning. It will show if element works but doesn't mean lower board is bad.
You know your cooling unit works cause it cools on propane.
Check the 5A fuse and test the element resistance....either one bad---replace element.