If the baseboard is tricking the thermostat into thinking the whole zone is satisfied, then the current temperature would read 69 when it's set to 69.
It's not. Here's my program for that zone. 11:30 at night, it drops to 65 degrees. Then at 4:50AM, it goes back up to 69. I checked the thermostat before I left the house this morning. At 7:15, it still showed a temp of 65. This was almost 2.5 hours after it was supposed to go back up to 69.
The radiators all get hot so again, I don't think it's a boiler problem.
Do you think the thermostat is bad? As I said earlier, it's relatively new. It's a Honeywell C3200 Magicstat 32. I'm running it on a hot water gas system with 3 zones. I have no idea if I have 2 wire or 3 wire zone valves.
How can I test the thermostat without replacing it?