Thanks 360!

It’s now 9 AM the next day.

All has been perfect for the past 24 hours (knock on wood). Actually had to back the propane heat down to 68 a few minute ago.

Aside from removing the panels, the only thing I did was remove this, then re-installed it. I didn’t even disconnect the two wires.

C340366P02 - American Standard OEM Furnace 3" Replacement Limit Switch https://www.amazon.com/dp/B00FEM579...K3TA6YAMKT3SBMA?_encoding=UTF8&psc=1

I doubt this part is an issue. From what I’ve read, it’s failure symptoms are cold air, and 24/7 can operation.

My fan is now cycling, as is the whole system.

But I have a new one on order anyway.

If I have another issue, and replacing it doesn’t help… then it’s service tech time.

But all perfect for now, and panels back in place.