Nest 4th Gen Humidity WAY OFF

[RussD27]

Recently installed a new gas furnace and 4th Gen Nest thermostat; we do not have a humidifier / dehumidifier.

Humidity reading on the Nest is always between 22 & 29% - actual RH in the home is usually between 70 & 80%.  Current outdoor RH today is 72% (it is winter here in Mississauga, ON).  

Why is the Nest reading so wrong???

[CoolingWizard]

@RussD27 ,

How are you measuring the indoor RH? The nest uses two separate sensors to measure RH in the area of the thermostat location.  To get a more accurate RH reading at the thermostat, turn on the blower fan for 1-hour.  This will circulate air and balance out the RH.

AC Cooling Wizard 

[RussD27]

I take back my 1st post...lol...my family heirloom barometer / hygrometer turned out to not be working!  It looks lovely, but at over 100 years old, it isn't working any longer...so I picked up a hygrometer and inside RH is 30ish, Nest says 27, so all is good.

[CoolingWizard]

@RussD27 ,

thank you for providing an update. I’m glad to know that things are much better for you and that you’re happy again. If you have any other questions or concerns about your HVAC system or your thermostat, controlling it always post here.

AC Cooling Wizard