Nest suddenly showing N260 code after working fine for over a year

[ksvenice]

We've had a Nest thermostat for over a year in our house without a common C wire.  About a month ago I got a low power warning so I changed the batteries.  Everything has been working great until today. First our AC decided to blow warm air out for about 30 mins.  Everything on the Nest was reading fine, except the indoor temp was going up.  Then just as suddenly, cool air started coming out.  Problem fixed (so I thought).  Now the AC seems to be working, but it's not cooling the house down as quickly as it should.  Indoor temp is set at 77 but it's been 82 for the past couple of hours.  And I just walked by the Nest and the screen didn't light up.  I touched the side and got a note of N260.  I know this is about a common wire, but it's never had that.  The AC is still blowing cool air but not it's just not as powerful as normal.   I will say that we are in the middle of a massive heat wave (it was about 106 today) so that may have something to do with it, but why the sudden N260 error when it's never happened before?

[Ryan_G]

Hi ksvenice,

Thanks for reaching out here in the Google Nest Community.

There are HVAC unit that works with the Nest Thermostat even without the C wire. There are also times that this behavior will show up and the only way to get it resolved is by connecting a C wire to your thermostat.

You could take a look at the HVAC unit and check if there's an unused wire that we can connect as C wire. If your unit doesn't have a C wire, check out this Nest Power Connector.

Regards,

Ryan

[Jake]

Hey ksvenice,

I wanted to check in and see if you managed to see Ryan's post. Please let me know if you have any questions from here. I would be happy to assist, and make sure you are good to go.

Best regards,
Jake

[ksvenice]

thanks for the reply.  I guess I'm trying to figure out why it suddenly doesn't work without the c wire even though the nest has worked for over a year without having one.  There is no c wire hooked up and I would prefer not to pay to install one or pay for a power connector.  And the nest still seems to work - I can control it no problem with the app.  I would just like to figure out how to clear this code.  If there is any way

[Jake]

Hey ksvenice,

I am sorry to hear the code is still showing, and being a bother. If your device is still working, even with the code. I would recommend trying to do a reset on your thermostat. This may remove the error code you are seeing. 

Best regards,

Jake

[Jake]

Hey ksvenice,

I wanted to check in with you, and see if the reset had helped. Are you still running into the error code? Please let me know, as I want to ensure you are good to go.

Best regards,

Jake

[Jake]

Hey ksvenice,

I wanted to check in with you, and let you know that I will be locking the thread in 24 hours.

Best regards,

Jake