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How to Wire a Doorbell

How to Wire a Doorbell

Is your doorbell not doing its job properly? Just bought a new one? Looking for easy instructions to wire it? Read these simple steps and your job will be done in no time.
Fatima Rangwala
It's hard to manage a house, by chance a big one, with a dysfunctional doorbell affixed on the front or back door. It is not difficult to replace or repair a doorbell. Before we read the instructions to wire the bell, let us look at some information on basic problems and understand a typical doorbell's layout.

Basic Troubleshooting
  • A normal residential doorbell's voltage is very low, ranging from 16-24 volts, except for the transformer's line side.
  • Do not follow instructions based on wire colors, as they differ; there are distinctively 18 gauge wires.
  • Check the transformer; the voltage tester should signal 16, 18, or 24 volts at both the transformer terminals. If there is voltage out there, check the chime of the doorbell.
  • Send your partner to the doorbell to hold the button; meanwhile, check for the voltage between the front screw and the common terminal.
  • If a correct voltage is received (16, 18, or 24), the chime is buggered.
  • Follow the same procedure for the rear button and screw too.
  • If the voltage doesn't flow through rear and front buttons when they are pressed, check for condition of the buttons.
  • If the voltage arrives at the chime unit, that's when you know you have a spoiled button to replace.
Layout of a Doorbell

A doorbell, being a closed-circuit system, consists of a chime generator, a power transformer, and an actual doorbell switch. In technical terms, it's called a SPST (Single Pole Single Throw) switch, which temporarily closes the circuit in the system. Such a switching action simply provides the power generated from the transformer to the chime unit, when the doorbell is lowered down to a limit. In short, a doorbell functions as a simple switching circuit.

Method for Wiring a Doorbell

Firstly, you will need to work on two wiring tasks. Now, the chime box, which has a power source of 110/120 volts, needs to be wired to the switches in order to receive power from a transformer. Doorbell wiring, in short, is wiring the chime into your home's power supply and also wiring the switch(es) into a transformer coming out from the chime.

Required Materials
  • Doorbell System
  • Wire Strippers
  • Screwdriver
  • 18-gauge Cable
Wiring Steps

Step #1: For safety purposes, disconnect the main power supply of your home. Then, slowly dismount the doorbell screws and accessories, and carefully pull the switch button away from the wall.

Step #2: Make sure you also disconnect wires from the old switch button.

Step #3: If you fear the wires will slip back into the cavity of the wall, tape them up with wire strippers against the wall. Also, try to hook all the wires to the screw's terminals on the switch.

Step #4: Shift your work to the place where the old chime unit is. Take off the cover plate and find all the screws that fasten the unit. Unscrew them, taking out the entire unit slowly.

Step #5: Before removing the wires, mark their correct connections so as to make it easier while replacing the new kit. You will find wires at the chime unit too, tape them the same way as you did in step #3.

Step #6: Now it's time to attach the wires back to new chime's base unit you have in your hand for replacement.

Step #7: Mount the new chime unit onto the wall carefully, using accessories in the new kit.

Step #8: Also, check for the measurement of the old unit and the new. If they don't match in size, mark new holes with a pencil, and drill them to fit the new chime.

Step #9: Use the markings you made for the wires, to connect them properly to the correct terminal of the new chime.

Step #10: Once that's done, put the cover plate back in its place and check the entire doorbell connection system for its working condition. If the doorbell rings or chimes properly, your wiring job is done here!

A wiring job is the simplest and safest, because it uses very low voltage to handle components. If the new kit has a wiring diagram, your job will be easier.