thanks for your answer. is it possible that if the furnace shuts off for lack of fuel, that the controller will reset after a certain period of time and stop showing that the zones are calling? reason i ask is that we have an overhead fuel feed that occasionally gets air bound and time will solve the gap.

klem1: 1) Thermostat says' Heating', and Sensi support confirmed that heating cycles all looked normal based on their logs 2) Turning thermostat to 'off' and back to 'heat' a couple of times, or turning power off/on at the furnace 3) see above 5) I have called Sensi support but only from work. Further troubleshooting has to be done at home but I need to be there during their support hours which might have to be next week. My mindset is I can't understand why the thermostat would behave differently (i.e. send a different signal) when the set point is changed vs when it is calling for heat to maintain a steady temp, and that it seems too coincidental that the new thermostat has exactly the same fault as the replaced one. Logic would suggest that that should rule out the thermostat as the problem since the common factors are the wiring and the furnace, which have both been working for several years.

Unless you like to live dangerously, it may be time or past time to consider replacing a 30+ year old furnace. If I were you, my next move would be to find a couple of recommended HVAC contractors and have them take a look and perhaps give you quotes. Good luck.

Sounds like something is amiss.