On Doorbell Systems
A friend promised to pay you back the $50 that you had loaned him over three weeks ago. You were supposed to be paid yesterday. Instead, you found a message on your answering machine that went something like this. “I rang your door bell for almost 15 minutes. There was no answer, so I figured you weren’t home. I will be out of town for a while. I’ll will bring you the money I owe you when I return”. That was the last time you heard from that friend. And all that was between you and payment was a broken door bell. Life does go on!
You guessed it. This weeks offering is about doorbell systems. How they work and how to repair them. Four components make up a doorbell system – 1) the push button, 2) the bell, buzzer or chime unit, 3) the transformer, and 4) the wiring.
Even though your doorbell may be working, there is a very common problem associated with doorbell buttons. Because most push button units are normally mounted with such small fasteners, the whole assembly often comes loose from the wall. Don’t be afraid to use larger fasteners (screws or lag screws) to reaffix it. This fix is easier than hanging a picture.
Because it is exposed to weather, the push button unit is a part of the system that fails most frequently. Exposure to weather can corrode wire connections in the push button unit causing a system failure. The fix is super easy – and the only cost – a little bit of your time.
There are two types of push button units and therefore two ways to access the wiring. Some push button units have pop-off covers that can be removed with the flick of a screwdriver. The pop-off cover type is recognized because of the absence of screw or nail head in the cover. The other type is screw-mounted. The screws are removed so that the push button unit can be detached from the wall exposing the wire connections in back.
CLEAN AND TEST THE WIRES
Once you access the connections simply unscrew the terminals and remove the wires from them. Use a knife, a piece of emery cloth or sandpaper to scrape or sand the wire until it shines. Touch the cleaned wires together. The chime should sound. If the chime doesn’t sound then the problem is one of the other components: the chime unit, the transformer or the wire. Replace the wires onto the push button terminals and remount the unit.
The problem of corrosion can also exist at the chime unit. Remove the wires at the chime unit terminals and clean them in the same fashion as you did at the push button unit.
If you have a voltage tester it can be placed on the chime terminals while the push button in pressed. If no voltage is read it probably means that the transformer unit needs to be replaced.
Voltage testers can be expensive. However you can make one from $2 worth of parts that can be purchased from your local junk yard. All you need is a tail light bulb, its socket and the two wires (about 10 inches in length) that protrude from the socket.
Since a door bell system is low voltage (usually about 10 to 18 volts), the 12 volt auto bulb unit can be used as a current tester. Each of the wires is connected to the chime terminals. When the door bell is pressed the light will shine brightly if the transformer is sending current to the chime unit.
Anyway, if the light lights it means that there is power in the system and that the wiring is OK. Since you have already cleaned the button this all means that you need a new set of chimes – that is if cleaning the terminals didn’t work.
Door bell systems are low voltage and therefore are not terribly dangerous. However, the transformer unit does have a high voltage (110v – 120v) side and can be very dangerous. Power should be turned off at the subpanel when modifications are being made to the system. Persons who do not understand electricity should not work on low voltage electrical systems while the power is on.
If it is discovered that a wire is broken in the wall, look into the price of a wireless door bell system. It could be less expensive to get one of these than to make a wire repair.
For more home improvement tips and information search our website or call our listener line any time at 1-800-737-2474! All you need to do is leave your name, telephone number and your question.