Nest Thermostat 3rd Gen buzzing sound from plate

[vcoderv]

Hello.  I have 2  3rd gen thermostats.  Whenever one zone calls for heat, both PLATES start making electrical buzzing sound.  I measured the voltage and it was 27V.   Sounds like it is in range with what i see on googles compatibility list (20v-30v) voltage requirements from the transformer.  Any idea what would make the plates produce that buzzing?  Thanks!

[cifuentesj]

Hi @vcoderv,

Thank you for your timely response and the comprehensive information you provided. I understand that you are encountering some issues when a zone calls for heat. You hear an electrical buzzing sound on both plates of your Nest Thermostat 3rd generation. I am here to help you and work together to find a solution.

To assist you with the best solution, I would like to get a bit more information:

• What troubleshooting steps have you already tried? If so, which steps have you tried already?
• When did the issue start?
• What additional sounds do you hear or produce besides the buzzing sound of electricity?

Please keep me posted.

Warm regards,

Jeremy.

[vcoderv]

Hello.  So , to troubleshoot the issue i got a brand new 24v 40va transformer and connected the base plate directly to it using low voltage 18awg wires.  The buzzing was heard still… I tried different plates, same thing.  I ordered replacement base plates, which should arrive today but something tells me I will have the same issue.  The buzzing exacerbates when the the device has called for heat…  any ideas at all?…

[cifuentesj]

Hi @vcoderv,

Thank you for your prompt response and the detailed information you’ve provided. To assist you better, you can get a hold of our support team by filling out this form, and they can take a deeper look at your specific situation.

Please make sure you leave your community thread and community username. Once you've completed the form, please let me know. This will allow us to investigate the issue further and find a solution.

Please keep me posted.

Warm regards,

Jeremy.