How to Replace a Doorbell

Remove the doorbell button from the wall by unscrewing the mounting screws and pulling it away. You'll see two low-voltage wires connected to the back. Touch the two bare wire ends together (this is safe — doorbell wires are only 16-24V). If the chime rings, the button is the problem. If not, locate the transformer (usually in the basement, attic, or utility closet near the electrical panel) and test it with a multimeter set to AC voltage. It should read 16-24V.

If the button was the problem, disconnect the two wires from the old button terminals. Strip 1/2 inch of insulation from each wire if the ends are corroded. Connect the wires to the new button's terminals (polarity doesn't matter on a standard doorbell). Mount the new button to the wall with the provided screws. Test by pressing the button — the chime should ring immediately.

Turn off the breaker that powers the transformer. The transformer's primary (high-voltage) side is wired to a junction box or the electrical panel. Disconnect the wire nuts connecting the transformer to the house wiring. Remove the old transformer. Mount the new transformer in the same location, connecting black to black, white to white, and green to ground on the primary side. Reconnect the low-voltage doorbell wires to the secondary terminals. Restore power.

If upgrading to a smart doorbell (Ring, Nest, etc.), remove the old button and connect the existing doorbell wires to the terminals on the back of the smart doorbell (polarity doesn't matter). Mount the bracket to the wall using the included hardware — use a masonry drill bit if mounting on brick or stucco. Snap the doorbell onto the bracket. Download the manufacturer's app and follow the on-screen setup for Wi-Fi pairing and video configuration.

If your chime is dead or you want to add one, turn off the breaker. Remove the old chime cover. Disconnect the three wires (labeled "Front," "Trans," and possibly "Rear"). Connect the same wires to the matching terminals on the new chime. Mount the new chime on the wall (use the old mounting holes if they align). Replace the cover. Smart doorbells can also send chime notifications to your phone and to smart speakers like Alexa or Google Home.

Restore power at the breaker. Press the doorbell button and verify the chime sounds. For smart doorbells, check that you receive a notification on your phone, that the live video feed works, and that two-way audio functions. Walk past the doorbell to test the motion detection range. Adjust motion sensitivity in the app to avoid false alerts from passing cars or pets.