English 
Door chimes, sometimes called doorbells, are a convenient way of having a notification that someone is at one of your doors. Sometimes having someone knocking doesn't alert you to visitors, but having a centrally located door chime to alert you can have its benefits. With a simple push of a button at the front or back door, you'll be notified that someone is waiting to enter your home via the door. Once the button is pushed, the chime or bell rings at a centrally located box that holds the chime/bell ringer. Door chimes have distinctive chimes for each door button. The front and back door rings are different so that you can distinguish between the doors.
Before beginning any electrical project, always turn off the power at the source. This may be a fuse or circuit breaker at your service entrance point, better known as your electrical panel. All electrical work must be done in accordance with local and/or National Electrical Code standards as applicable.
Check your door chime box to see what is included and what you have to purchase in addition to the chime to make it functional. It is likely that you'll need additional parts and wiring unless the door chime comes as a complete kit.
We’ll be discussing the installation of a Broan two note door chime, Model C905. Included are the door chime and the chime cover plate. You will need to purchase a 16-volt AC transformer, two-door chime buttons to activate the chime, and some door chime two-conductor wiring. It is likely unless you have an electrical junction box close that you can tie into a circuit to feed the door chime transformer, you’ll need a junction box, cover plate, wire connector, wire nuts, NM electrical wire, and a wire connector or two.
As with any electrical project, you will certainly need a few electrical tools. To aid in installation time, a drill and drill bits will help quite nicely. You’ll also need a Phillips screwdriver, wire strippers, needle-nosed pliers and possibly a hammer. You’ll need to drill small holes to insert the two screws that hold the door chime up on the wall and also the two screws that hold the two-door chime button up on your door trim. The screw driver is used to install the screw, the wire strippers for the Nm wire and the door chime wire, and the needle-nosed pliers to bend the wire to fit under the terminals.
Turn off the power to the junction box that you’ll be feeding the transformer for this door chime. If there is a junction box with a circuit that you can tie in to, knock out the knockout and install the transformer, wire side first, into the knockout opening. If not, run a 12-2 electric wire with ground NM wire, from the circuit breaker panel to a junction box that you’ll have to add. Use wire connectors to hold the wire securely to the electrical panel and the junction box. Use the wire strippers to strip the NM wire and the transformer wire ends, if they aren’t already. Connect the two black wires together with a wire nut, the two white wires tie together with a wire nut and the ground wires together with a wire nut, but the ground wire should have a pigtail wire added to bond the ground to the box. Cover the connection with a box cover. On the other end of the wire, add a circuit breaker if needed to the panel to complete the installation.
Run the two conductor low voltage wiring from the front door to the door chime. Now, run the door chime wiring from the side or back door to the door transformer. These two wires should be marked front and back door to keep them straight. Also, run a third wire from the door chime to the transformer. This will feed the power to the door chime. Bring the wiring through the access hole in the chime mechanism. With the wire strippers, strip the outer sheathing from the three wires. On the power feed wire, tie one side of the transformer to the center terminal of the door chime. The other wire connects to the second terminal of the transformer and also to the black wires of the two-door wires. Use a wire nut to connect these together. The white wire will connect to the front and back door terminals of the door chime, as you have already marked these earlier.
At each door, you now have a two-conductor wire. From the inside of the house wall, drill out through the door trim and insert the wiring out through the hole. Strip the wire sheathing and expose the two wires. Strip the individual wires and install them on the two terminals on the button. Now, install the two screws that will hold the button on the door trim.
In order to test the newly installed door chime, you must first turn on the power at the electrical panel. Turn on the circuit breaker and go to the front door. Push the button and see if the chime rings. If so, go to the back door button, push it, and see if it rings. If so, you have correctly completed the installation of your door chime. You will notice that the front door button causes the chime to ding twice, while the back door button rings it only once. This is to allow you to know which door your company is standing. Congratulations! Now you’ll know when someone is at your door.
