Thinking v2
It happened again about 9:00 last night, so I beat feet to Home Depot in the Springs and got there about 15 min before closing. Picked up two different 'stats (one identical to the one I have, one a step up but on sale for the same price). Plugged in the new twin, and success!........ Ummm.... No. 4 AM, furnace making noise, t-stat dark, no heat. Long story short, I traced it down to what I think is a cracked solder joint where the t-stat terminal strip is connected to the controller. Working now, but will pull the board and reflow those points. I guess it's good that I took PTO today.












