Nest 3rd gen Thermostat low battery issue after several years

[ErnieC6720]

After about 4 years, my NEST is now going to low battery and disconnecting from WiFi.  I can recharge with usb but doesn't seem to be charging on the wall.  Nothing has changed in my home.  Can these rechargeable batteries be replaced?  Could it be something else?  It hasn't happen before.  Maybe once after a power outage but never again.  Any suggestions would be greatly appreciated. 

[Greygeek]

Hi !  

I had this problem two-years into my NEST Gen3.  I could use external USB to charge it, but it wouldn't hold the charge when mounted on the wall.  Turns out that my 20-year old small 24 volt transformer was in the process of failing, and only put out about 17 volts.  Strangely enough, the furnace kept operating, but the NEST battery wouldn't charge.  I replaced the 24v transformer in the basement and all has been well.  

That said, my NEST will be 5 years old soon, so your post has me wondering if I'm going to need a battery replacement.  

[ErnieC6720]

My HVAC system is about the same age as the nest so I am not sure it would be the issue or even how to check for that. 

[Greygeek]

Using a voltmeter, go to the furnace where the wiring from the NEST is connected. You should have 24 volts between the red (R) and the (C) connection points. 

[ErnieC6720]

I have 4 Wires.  They are Cool-Y1, Fan-G, Heat-W1, and Power-RH.  I don't have any wire going into the C port

[Brucembh]

I don't have one either.  No battery issues for two years.  Now it is happening.  Battery is just over 3.6 volts.  That is supposed to be ok. 

[jungliebeats]

After speaking to Google Nest advisor this evening the battery needs to be between 3.8 - 3.9 volts in order to work and stay in touch with the Wi-fi etc. As mine wouldn't hold the charge after only 15 months they have replace my thermostat free of charge. Hope this helps.

[Mayndog]

Where does the battery live? 3rd gen

[jpclark]

I have the same problem. what number did you call to speak to a live person

[MikeGuenther6]

What number did you contact to get the replacement thermostat?

[MikeJeffries]

https://support.google.com/googlenest/gethelp?hl=en

i gotmy replacement- no issues yet

[Pulella]

I tried to contact technical support via phone and the 855 469 6378 is no longer in service. Cannot find a replacement #. Any idea?

[MikeJeffries]

Why are you calling them? Go to the link and when you get to the bottom., click call. They call Y OU.

[EdB]

Same here and same issue. Pull unit and charge for 3 hours. Plug back in and only works for a few days. Then have to pull and charge again.

[TXRick]

At least now with this heat wave, having the AC on all the time is recharging my thermostat batteries..

[EdB]

Will opened a ticket with support. After sending in power readings ask me to charge unit for 24 hours to prove it was a WiFi problem???? I've charged it for 24 hrs and been using it for a day. Still no clue how that proves it's a WiFi problem.

[MikeJeffries]

I went through all of this with 3 different reps, 3 different answers. the last one understood it's a problem with the internal battery (which lasts like 5-10 years supposedly). Let them know the internal battery is dead it seems and only lasts 1-2 days on a charge and it needs an RMA. They can send you one upfront if you pay for it (they pre-auth your card) but then they release and refund it.

[NoNameLeft2Take]

Oddly have the same issue as well.  Installed my Nest Thermostat a little over  year ago (with no "C" wire connected) and it worked fine.  Now all of sudden it's reporting low battery and dropping the wi-fi connection repeatedly.  I've tried charging the unit via the micro-usb port and it seems fine initially but then quickly reverts back to low battery/wifi dropping behavior.  Struggle to understand why all of sudden now the lack of a connected "C" wire is an issue.

[rrobster]

I have learned the hard way (from personal experience) that you do want to attach the dark blue wire (if you have it available) to the "C" connector on the mounting plate. This will trickle charge the battery and keep it above the minimum voltage required for a WiFi connection.

[Jeff]

Hi ErnieC6720,

I just wanted to jump in real fast to see if you saw rrobster's reply and to see if you still needed some help on this or if you were able to get it sorted out. If you are still needing some help, just let us know and we'll be happy to continue helping.

Thanks,
Jeff

[Coachcotter]

Jeff, I’m having this issue as well. I’ve taken every step everyone has mentioned. Multiple times. No luck. 

[EdwardT]

Hi folks,

@-MBS, thanks for the update. Let us know if you're still experiencing the same issue once you received the replacement.

@Musicm9986, @JiveJimmy, @Coachcotter, I'm sorry to hear that you're also experiencing this issue. Could you check the power reading of your Nest Thermostat by going to Settings > Technical Info > Power?

Thanks,

Edward

[Coachcotter]

Edward,

my power reading is 3.527 V

[Lou999]

what is a good reading?  I just installed a new unit and within 10 minutes got a low battery situation at 3.65v.    Charged it for 2 hours, put back in and had 3.9.  it's now down to 3.72v.   Any idea what a normal reading is?

[JiveJimmy]

3.17 volts.  Thanks for looking into this. 

JM

[EdwardT]

Hi folks,

Thanks for the response. Could you also share the VOC, VIN and IIN readings? Also, how is your Nest Thermostat wired?

Thanks,

Edward

[Trex56]

Voc 35.25

Vin 23

lin 20ma

Y1  G. W1. Rh

i don't have a C wire to connect 

[Chrsprc]

I can't get my best to power up
long enough to get a reading now. It powers up long enough to reboot then die. I've left it on the charge now for several hours and it won't power up long enough to reboot on the wall. It just dies. What do I do now?

[MikeJeffries]

Can you help me... I have a Forced Air system i replaced last year when i bought this new house. The control board has 4 wires (no c-wire),  but i think there is a c-wire spliced to the R wire in the wall somewhere, as I have it working on AC and Heat thru the thermostat with the following connections below...  One rep said it could be the battery, one said could be transformer, one said you need a constant power source so i have to supply a c-wire (which this doesnt require so i dont quite understand any more)

CONNECTIONS AT CONTROLLER: W-white, R-Red, G-Yellow, C-BLACK*

At NEST i had to connect it as follows:

Y1- BLACK, G-YELLOW, W1-WHITE, Rh - RED

Its worked since october no problem at all - 2-3 weeks ago (beginning of march - 4-5 months later, it wont hold a charge and i have to charge it with a usb cable every 1-2 days now)...

As of right now, its working from a charge we did about 1.5 days ago and the power shows 3.71 volts, Voc 33.03 Volts, Vin 22.87 Volts, and lin 20mA(i)

What do i do?

[Shabellabu]

Help in having the same problem, low battery and it disconnects from wi fi 

[Mark63]

Same here no luck , Ike to ditch the nest! Over priced junk.

[abwatson]

I just discovered this thread. I am having same problem (not charging, charges w/usb). What is the correct solution? Since we have no AC, perhaps C wire not connected?

[Nicolina]

I am having this issue and need assistance please Jeff?!

[Loulou2]

Hello. I am experiencing the same problem and it is impossible to speak to come one at Google without advising me of 1000000 troubleshooting pages that do not help. Can you please help me to contact someone 

[mjd]

https://www.amazon.com/gp/product/B08TWDT4J2/ref=ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&psc=1.    I had the battery issue and installed this and it appears to have fixed the issue..good luck..

[krroller]

I am experiencing the same.  Google tech support has given me steps like take if off the network, then reset it, wait 24 hours, etc.   I'd like to try replacing the battery but Google will seemingly not comment on the life of the battery and when to tell the battery just won't take a charge any longer.  I can charge it via USB for a few hours to get a full charge and it lasts about a week before the battery gets too weak and I lose connections to wifi and remote sensors shut down.  I have 4 units that with Trane HVAC equipment that was all replacing a few years ago.   I have this issue of the battery going dead that started recently on three of the thermostats.  Taking them off the wall charging via USB seems to last 1-3 weeks before the battery gets low again and the thermostats shut down WiFi connectivity.

[Epilepticragdol]

I can’t find if this has been resolved. How do you fix this before I just throw my third gen away.

[Ccrawf]

I'm thinking that throwing the Nest thermostat away and going with a different brand or product that last longer then 2.5 years is the way to go. It's very frustrating. They have a problem that needs to be resolved.

[Pulella]

I installed my Nest learn Thermostat, 3rd gen, a little over  year ago (with no "C" wire connected) and it worked fine.  Now all of sudden (17 days ago) it's reporting low battery and dropping the wi-fi connection repeatedly.  I've tried charging the unit via the micro-usb port and it seems fine initially but then quickly reverts back to low battery/wifi dropping behavior.  The tech svc # is disconnected. What to do?

[MikeJeffries]

Thats  what happened to me - in under a year. I assume its powered by a lithium ion batter inside  the unit since we dont use a c-wire. it took me 3-4 calls until one person understood the issue and approved an RMA. Most think the c-wire is still needed!

Start here: https://support.google.com/googlenest/gethelp?hl=en