05-12-2022 11:22 AM
Hello everyone! I have a dual zone HVAC and seem to have a small issue. Both zones have a nest thermostat hooked up (one runs most floors while the other runs only upstairs bedrooms and living room in townhome). Both show approx the same metrics; Vin: 36, Lin: 385, PS: C-385 while the AAA read 3.2 volts new. The upstairs unit goes through the AAA batteries in about 2 months while the downstairs has yet to be changed (approx 11 months and going). Upstairs is used a little more with HVAC system. Any thoughts on why the upstairs nest is using more batteries? Thanks!
05-12-2022 09:53 PM
Do you have a C wire installed on either?
Post a picture of the zone controller's wiring.
05-13-2022 01:33 PM - edited 05-13-2022 01:33 PM
Not quite sure how to post a picture on this forum but I have a picture
05-13-2022 01:34 PM
Here is another pic
05-13-2022 11:50 PM - edited 05-14-2022 12:54 AM
Looking at this picture and on the right are two two connection points for the thermostats, the second terminal from the bottom of each terminal block is the C wire connection point. It looks like the black wire going to your thermostats is a C wire. Where does the black wire connect to on the Nest thermostats?
05-14-2022 03:49 AM
Goes here:
05-14-2022 03:50 AM
05-14-2022 09:23 PM
Do you have a multimeter or such that you can use to measure the voltage between the red and black wires?
Are both the upstairs and house thermostat the same? If there are, have you tried swapping the displays on them and see if the battery issue follows or stays?
05-15-2022 04:05 AM
Haven’t tried swapping the displays yet that is a good idea
05-18-2022 01:19 PM
Hi Nestuser1111,
Thanks for reaching out here in the community.
I'd like to jump in here and check if you've already tried swapping the Nest thermostat display. Let us know how it goes by replying to this thread.
Thanks for your help, Patrick_Caezza.
Best regards,
Ryan
05-21-2022 02:17 PM
Hey Nestuser1111,
I just wanted to follow up and see if you're still in need of help. Please let us know as we would be happy to answer any questions you may have.
Best regards,
Ryan
05-22-2022 11:56 AM
Yes I first tried re seating the C wires to see if that was the problem and am currently testing that method. I will swap if low battery happens
05-22-2022 03:23 PM
Hey Nestuser1111,
Thanks for the update. Let us know how it goes by replying to this thread.
Best regards,
Ryan
05-25-2022 03:50 PM
Hey Nestuser1111,
I just wanted to follow up and see if you're still in need of help. Please let us know as we would be happy to answer any questions you may have.
Best regards,
Ryan
06-02-2022 08:14 PM
Hi,
We haven't heard from you in a while so we'll be locking this thread if there is no update within the day. If you have any new issues, updates or just a discussion topic, feel free to start a new thread in the community.
Best,
Melba
05-14-2022 07:08 AM
Thinking about it maybe a good start would be just a reseating of the zone two black wire to make sure has a good connection if the zone one batteries are lasting a long time maybe it’s just the connection with the C wire and zone two?