Congratulations on using a meter to find the exact issue.
Bought it at Lowe’s and installed around the third quarter of 2019, I doubt this model was available in 2002.
It looks like perhaps two of the 3 capacitors that are sticking out of the rear may be swollen. That means they are bad. Those caps are likely in the power supply section of the thermostat. If you got it in 2019, you should be able to get it replaced.
The lowes statement says it all.
The raised X's on the capacitors makes me suspicious. Linear power supply needs the caps to filter the rectified AC and this sort of failure would explain why it was unusually warm.It was very warm when I pulled it off the wall.
There's a d&l supply in Rock Hill. If that's close enough to you. Figure which one you want. Let me know. I'll get one put on hold, and you can swing by, pay for it and pick it up.
Welcome to my world.On a side note, we built this house in 2019, and I replaced both electric motors in the “things” in the attic that blow the air (squirrel cage fans?). Didn’t last the first year. What a PITA that was.