From simple ding-dong bells and buzzers to sophisticated chimes capable of ringing out a custom tune, modern doorbells offer a wide range of choices for the DIY homeowner.
But while the styles and sounds may vary greatly, installation is essentially the same for each.
All doorbell systems—with the exception of wireless models—utilize a step-down transformer to reduce the home’s normal 120-volt circuit to the much lower voltage required by the doorbell system.
The voltage needed can be anywhere from eight volts to 24 volts, so it is very important to purchase the correct transformer if you’re not purchasing a doorbell kit that already includes one.
How to Install a Doorbell or Chime
Tools and Materials
- Insulated screwdrivers
- Power drill and bits
- Fish tape
- Voltage tester
- Wire strippers
- Torpedo level
- Needle-nose pliers
- Caulking gun
- Silicone caulk
- Ladder (if necessary)
- Wire connectors
- Doorbell buttons
- Doorbell chime
- Low-voltage bell wire (two-wire for running from switches to transformer)
- Low-voltage bell wire (three-wire for running from the transformer to the chime)
- Plastic anchors, toggle bolts or masonry anchors
Step 1: Turn Power OFF
In every job in which you work with electricity, start by turning off the circuit breaker that delivers power to the circuit.
Use the voltage tester to make sure the voltage is off.
Step 2: Run the Bell Wire
You should have two different types of bell wire for this installation: one that has two wires and a second with three wires.
Run the two-wire bell wire from the transformer to the point where the doorbell button(s) will be installed. This will require you to use a power drill and fish tape to navigate the wires through the walls, across the ceiling, etc. Mark the wires with tape at the transformer so you know which one goes to which doorbell.
Next, run the three-wire bell wire from the transformer to the place where you are installing the chime.
Step 3: Mount the Chime
Position the chime on the wall where you want to install it. Place a torpedo level along the top to ensure it is level and use a pencil to mark its mounting holes.
If the wall is drywall, plastic anchors or toggle bolts will be suitable for mounting the chime, but if the wall is constructed of masonry material, screws with expansion sleeves or masonry anchors will be required.
Secure the chime using the anchors while keeping the bell wire accessible.
Step 4: Connect the Wires at the Chime
If you are installing a two-button doorbell system, the chime should also be supportive of two buttons. It should have three terminals, labeled F, T and B.
- F = Front door button
- T = Transformer
- B = Back door button
At the chime, the bell wire is three-wire, so remove about four inches of outer sheathing, and you will see a black wire, a red wire and a white wire.
Strip about three-quarters of an inch of insulation from the ends of each wire using the wire strippers.
Loosen the three terminals and secure the red wire under the terminal marked F; secure the black wire under the terminal marked T; and secure the white wire to the terminal marked B.
Once the terminal connections are tightened down, install the chime cover.
Step 5: Wiring the Doorbells
Each doorbell should have a two-wire feed already in place. Remove about two inches of outer sheathing, and you should see one red wire and one white wire.
At the front doorbell, strip three-quarters of an inch of insulation from the end of each wire, and then connect the red wire to the bottom screw on the doorbell and the white wire to the top screw.
At the back doorbell, strip three-quarters of an inch of insulation from the end of each wire, and then connect the white wire to the bottom screw on the doorbell and the red wire to the top screw.
Apply a bead of silicone caulk in the holes from which the wires extend and secure the doorbells to the jams using the included screws.
Step 6: Wiring the Transformer
At the transformer, you should have one three-wire cable and two two-wire cables (labeled per doorbell). Remove about four inches of outer sheathing from all three cables and strip the ends of all of the individual wires. Make your wire connections according to the following instructions:
- Connect black wire from the chime to one of the terminals on the transformer.
- Connect the red wire from the chime to the red wire from the front doorbell button.
- Connect the white wire from the chime to the white wire from the back doorbell button.
- Take the white wire from the front doorbell button and the red wire from the back doorbell button and twist them together and connect them to the other terminal on the transformer.
Make sure all wire connections are capped with a properly-sized wire connector with no copper wire exposed.
Turn the circuit breaker back on and test your new doorbell chime system.
This article was updated from an earlier version by Dave Donovan and published on realtor.com. See the original article here.