Good afternoon! I'm sorry it took so long to get back to you. The morning trip took longer than I anticipated.
The reset for your Honeywell control system is in the installer set up. It's ISU number 710. You simply change that function's parameter to 1 then back to 0. I don't remember if it gives you a warning and a chance to cancel. I've only done this once on the IAQ/EIM type system and don't remember. After performing that reset you should also remove the battery in the thermostat and power down your furnace to remove ALL power to the control system for 5 minutes or so. Just to doubly ensure your system is reset from scratch!
After that, replace the battery, power up the furnace and you will have to proceed with programming the system through the ISU table. I would turn power off to the OUTDOOR unit during the reprogramming. It's not necessary for that unit to be powered up during all this. Below are links to both the ISU table and the operating manual for your thermostat. You will find the pdf with the ISU table is quite extensive. Fortunately it is also very thorough and gives an explanation for all ISU's. The important settings are in the beginning of the ISU, set the date and time, the system type, the number of stages of heating and cooling. The fact that you have a dual fuel heat pump system will affect MANY ISU's! I can help with that if you have questions.
ISU programming manual:
Thermostat operating manual:
If you'd like, I can offer an Additional Services offer where I will create a document giving you ALL settings for your ISU table. I can do that for an additional $50. To do that I would need some additional info from you, such as your zip code for average weather conditions in winter, what kind of humidifier
you have and likely others that I can't think of in the moment.
Bear in mind this is kind of a last ditch effort. Your system is confused with the fan control and I can't guarantee that it will recover properly. We may do all this and end up in the same boat. Whether it's worth it, is up to you!
Let me know how you want to proceed and I'll help in every way I can.