Installing 2 Nest Doorbell cameras in a 3 wire chime box

[mattrogo]

We have had 2 nest doorbells (1st generation) for our front and back door for about 3-5 years.  We hired a Nest Pro to install them.  This past week in Wisconsin the weather was very cold and both cameras stopped working.  We have replacements (2nd generation Nest Doorbells), but are unable to install due to not remembering how to wire the chime connectors.  We have 3 wires in the chime box-front,  back, and transformer.  Have not found good instructions online for setting this up.  Any help would be greatly appreciated.  We could not use the old pucks, and we cannot figure the wiring for the new ones. 

[MplsCustomer]

@mattrogo 

See the "Two Nest doorbells, two chimes" diagram in this Help topic. It's mislabeled; it should say "Two Nest doorbells, one chime." (I've asked them several times to correct the title.)

https://support.google.com/googlenest/answer/12153643

You might also want to check your transformer. Many customers in this forum (including us) have reported having to upgrade to a 16V 30VA transformer to get both 1st gen and 2nd gen Google Nest doorbells to work.

[mattrogo]

So, from the diagram, it looks like one wire of chime connectors goes

to either front or back door terminal and then the other wire of the chime connectors goes on the transformer terminal.  It looks like the transformer terminal will have three wires on it then.  Correct?  Is that safe to do?

[MplsCustomer]

@mattrogo 

That’s similar to how the 1st gen chime connector is wired. 

[mattrogo]

I am pretty sure I only have a 24v transformer.  I am linking the transformer to this message.  Would I need to replace it before installation?  How would I go about doing that?

[MplsCustomer]

@mattrogo 

I think your transformer is sufficient.

I take back my comment about the 2-doorbell 2nd gen diagram being similar to the 2-doorbell 1st gen diagram. The 1st gen chime pucks are wired differently.

Hopefully, Google Nest knows what they're doing in the 2-doorbell 2nd gen diagram.

[Lance_L]

Hi folks,

@mattrogo, thanks for reaching out to the Google Nest Community. I wanted to check in to see if you still need help with your Nest doorbell.

Here’s a wiring diagram on how to connect two Nest Doorbells (wired, 2nd gen) to one chime.

Also, here’s a handy guide on how to install Nest Doorbell (wired, 2nd gen).

Let me know if you have any questions.

Thanks for your help and feedback, MplsCustomer.

All the best,

Lance