I wired up a nest hello doorbell to my existing chime. It rings fine but lacks enough power to operate properly. That’s ok, it was a little expected.

Unfortunately, changing the old transformer is not an option due to its placement and some external factors.

Per hello instructions, I have bought a plug in transformer. This allows the hello to work without the chime.

What I would like to be able to do is power the hello with the plug in transformer and have the chime ring at the same time. Is this possible to achieve safely?

I have attached an image of my chime currently wired.enter image description here

1 Answer 1


Make sure your new transformer has enough power for both your chime and the hello. I would not continue to use the old transformer. I would disconnect the power to the old transformer and rely on the power of the new transformer to operate both the old chime and the hello.

It looks like your old transformer is connected at the "0" and "3" terminals. Remove those and cap them off. Connect your new plug in transformer there.

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