Nest Doorbell with existing wired vintage indoor mechanical bell

[TonyMK]

I have a vintage wired indoor bell run off a Friedland transformer with an output that says 3-5-8V 1A. I believe I need to upgrade the transformer to one with more power but won’t this ‘fry’ my existing indoor bell?  Is there a way to keep the original mechanical bell so that it still rings when the Nest doorbell button is pressed?

[AndersC]

Hi @TonyMK,

Thank you for posting in the community. I understand you want to install your Nest doorbell with your existing wired indoor mechanical bell. I'm happy to assist you.

Depending on the model of your Nest doorbell, it must be connected to your home's doorbell system. In some homes, you may need to upgrade your transformer to meet the doorbell's higher power requirements. If it's not compatible, you can either contact a local pro to upgrade your system or install your doorbell with the indoor power adapter.

The table below compares the voltage and power required for Nest doorbells to work with your home's doorbell system.

	Nest Doorbell (battery)	Nest Doorbell (wired)	Nest Doorbell (wired, 2nd gen)
Voltage	8 to 24 V AC	16 to 24 V AC (North America) 12 to 24 V AC (Global)	16 to 24 V AC (North America)
Power	10 to 40 VA	10 to 40 VA (North America) 8 to 40 VA (Global)	10 to 40 VA (North America)
Frequency	50 to 60 Hz	50 to 60 Hz	50 to 60 Hz

To determine if your mechanical chime is compatible with your Nest doorbell, first check how your doorbell and chime are powered. You can find more information in the article Check Nest doorbell compatibility.

Let me know if you have any further questions.

Regards,

Anders

[TonyMK]

My existing doorbell is powered by a Friedland transformer with an output that says 3-5-8V 1A.

[AndersC]

Hi @TonyMK,

Thank you for replying. Based on what you mentioned about your transformer, I recommend that you upgrade both your chime and transformer, since the voltage between the transformer and the chime is as important and as required as the voltage between a Nest doorbell and a transformer.

Keep me posted.

Regards,

Anders