Should I replace my doorbell chime transformer?

I bought and installed a Ring Doorbell Wired (the black one). I bypassed the existing chime, that uses an UK RDL M412 transformer (8-24V). When configuring the camera, it fails by saying something like “Your transformer does not have enough power, please replace with a 16-24”, however the specs said it should work with 8-24.

Am I doing something wrong? Do I have to buy a new transformer? Which one? Can I replace it myself or do I need professional services?


Hi @Piccoli. It is possible that your transformer is underpowered. In addition to needing 16-24 VDC, it also needs 30 VA (Volt Amps). This Transformer here is known to work with the Doorbell Wired. It is not a difficult installation, but if your don’t feel comfortable with electrical work, it may be best to consult a qualified electrician in your area.

I believe it is an issue with the App not being updated to work correctly with the lower bound AC requirements of the Video Doorbell Wired. See here:


I happened to get a hold of an indoor 24VDC (yes, DC) power supply and was able to complete the set up of the Video Doorbell Wired using the iOS App. After it was set up and connected to my Ring account, I installed it outside, connected to my 12VAC transformer.

It has now been working for 4 days on 12VAC without any issues. The iOS app, in device health, still says my transformer is under powered and that I should by a Ring Transformer.

If your transformer is at least 8VAC, that’s the minimum listed on the UK website (the US minimum is listed as 10VAC), try to get an indoor 24VDC power supply, just to use temporarily for set up. I’d say buy one from Amazon ( and then use their lenient “Return for any reason” policy once you get it working.

And you might need a different temporary power supply for the UK, maybe this one (sorry, won’t let me post it as a direct link):

amazon .co .uk

you’ll have to check that out on your own.