Nest turned off, will it change when the fan is on even though I don't have a C wire?

[hathaway65]

A few interesting points here.  I noticed that my Florida home was not cooling and the thermostat was not on-line. When someone approached the Nest it said battery low, restarting/shutting down, which it did.  Turns out that was only part of my issue.  Removed the Nest and plugged it in for 15 mins and re-attached on the wall.  Nearly fully changed?  Turns out that a humidistat next to the Nest was turned from 100 percent (on) to 50 percent that essentially turned off the power to the Nest.  Turning the Humidistat back to 100 and the Nest returned to normal.

Here is my question.  When the A/c fan runs, does that trickle charge the battery in the Nest with no C wire being attached/used? Because in the app the battery showed 3.86 when originally re-attaching it to the wall.  Now, 24 hours later,it shows 3.88. How can the battery be charging if there is no C wire in use?

What is the highest level of battery I should see or want to see here?

Should I spend the 300$ on having a C wire run from the unit to the Nest?

I want to avoid any issues as the place could be empty for a month at a time or more and don't want issues.

Any help here might help.

Thanks

[Patrick_Caezza]

Which Nest thermostat do you have?

The easiest and least expensive way to add a C wire is to use the Nest Power Connector.

[hathaway65]

Sorry.. Nest Learning Thermostat. 

Thanks

[Ryan_G]

Hey folks,

Thanks for visiting the Google Nest Community. 

Since this thread hasn't had activity in a while, we're going to close it to keep content fresh.

If you have additional questions, feel free to submit another post and provide as many details as possible so that others can lend a hand. 

Hope this helps!

Kind regards,

Ryan