Broken Doorbells, Buzzers, and Chimes - Troubleshooting Signaling Systems

Troubleshooting Signaling Systems- Fixing a broken doorbell, buzzer or chimes.

Signaling systems such as doorbells, buzzers, and chimes consist of a push-button, a signaling unit, and a transformer. It is normally safe to work on faulty signaling systems without shutting off the main power. However, the transformer may be defective, either relaying no current or failing to reduce it. Therefore, first check the transformer with a volt-ohm meter. If the transformer is producing too much power or no power at all, it should be replaced. If it is working properly, you may check out the system without turning off the main power. Be safe either way.

Next, check the whole system for breaks in the wiring; splice any you find. If the transformer is working properly and all wiring is intact, dismantle the push-button and test it by shorting it with a screwdriver. The button's contact points may have been corroded by exposure to weather, and need cleaning. Repeated use can weaken the button's internal spring mechanism. If this seems to be the case, replace the button.

If the button is working properly, check wiring connections inside the signaling unit- the chimes or bell. Poorly connected wiring at either the transformer or signaling unit can cause a system to ring continuously or not at all. If all tests lead you to conclude that the signaling unit itself is faulty, replace it.

Chimes: Loose wires will result in sporadic ringing. Fix by tightening terminal screws. Markings indicate connections: FR to front door buzzer, REAR to rear door buzzer (if any), TR to transformer.

Transformer: It cuts household current from 120 volts to about 10 volts for bells and buzzers, and to about 16 volts for chimes. It is often found on a basement beam.

Testing Transformer: Set volt-ohm meter to 25 VAC scale, attach leads. If it reads less than about 10 volts, or more than 16 volts, replace with new transformer.

Push-button: Two wires link button with chimes or bell and transformer. Depending on type, either unscrew the plate or pry button out, using a thin screwdriver. Testing the button, to avoid a shock, be sure transformer is functioning properly. Then, use a screwdriver to make contact across both terminals. If chimes sound, replace the button.

Cleaning corroded terminals: Either spray them with an electrical contact cleaner or remove wires and sand all corrosion from wires and screws with fine sandpaper. Wires will spark if they touch.