Nest thermostat

[scubatech2]

I live in florida and we have been having sweltering heat herw since july 2023. Have had nest thermostat over a year. Worked great till update last month. Update was adjusting thermostat settings to be more economical. I didn't know the new update was over-riding my presets till i noticed temp changes going on 7 days into the change. Maximum daily change was .3 of a degree. I cleared all that out and reinstalled my original presets and it worked ok for 4 days. Yesterday in middle of day, thep settings went beserk, heat rose inside 4 degrees before ac turned on, temp setting was reading 71, humidity was reading 99%. I could not clear any of this till i unlinked with Matter on the unit. Reinstalled my presets and they are currently working ok but humidity is jumping between 74% and 98% and everywhere in between. Any one else seen this going on?

[CoolingWizard]

@scubatech2 ,

If you humidity is jumping up and down by so much, your indoor evaporator coil is likely icing up or the condensates are not draining properly.  If water in the condensate drain pain is not draining, it will evaporate back into the air.  Find the drain pipe outside the home, and use wet/dry vac and such the water out.

AC Cooling Wizard

[scubatech2]

With 90+% humidity outside constantly, there is always some water from condensation in the drain pan. It is constantly draining and the ground outside has a small pool from drained water. I placed a hygrometer next to thermostat and it constantly reads 54%. Where ever i put hygrometer, the reading stays close. It has a high and low reading also  55-53. I've used vacuum couple times a year for years to keep drain tube open to outside. Will do so again today. Had new ac and matching a coil replaced last fall.