Symptoms
- Old mechanical chime buzzes constantly or not at all after install
- Doorbell works fine in the app but the wall chime never rings
- Chime rings once and then stops working
- Manufacturer's compatibility checker flags your transformer as unsupported
Likely causes
- CommonExisting transformer voltage too low or too high for the new doorbellVideo doorbells often need 16–24V AC, while some older systems run outside that range.
- CommonDigital chime not supported by the doorbell brandSome digital door chimes are incompatible with certain video doorbell electronics even at the right voltage.
- PossibleMissing or incorrectly wired resistor/chime kit accessoryMany video doorbells require a small included resistor or bypass kit wired at the chime to work with mechanical chimes.
- PossibleMechanical chime simply not supported by the model at allCertain doorbell models are wireless-chime only and cannot trigger any hardwired chime.
- Less commonWiring reversed or loose at the chime unitPolarity generally doesn't matter for chimes, but a loose connection will cause intermittent operation.
What to do
- Check the manufacturer's website or app for a chime compatibility checker and enter your existing chime's brand/model.
- Confirm your transformer's voltage rating on its label matches what the doorbell manufacturer requires.
- If the doorbell included a chime kit or resistor, verify it was installed exactly per the included instructions.
- For digital chimes, check whether the manufacturer explicitly lists it as unsupported.
- If the mechanical chime is not supported, disconnect it and rely on the doorbell's app and phone notifications.
- Add the manufacturer's plug-in wireless chime accessory as an alternative to a physical bell.
- Replace an outdated or underpowered transformer if the doorbell manufacturer recommends a specific voltage.
Tools and parts
- Voltage tester
- Screwdriver
Doorbell transformerSearch: “16–24V doorbell transformer”
Plug-in wireless chime accessorySearch: “video doorbell plug-in chime”
When to call a pro
If you need to replace the transformer or aren't comfortable working at the breaker and chime wiring, hire a licensed electrician.
Safety
Use caution
Turn off the breaker that powers the doorbell transformer before disconnecting or reconnecting any chime wiring.