How to Fix a Broken Doorbell
Doorbell circuits are not powered by 220-volt grid voltage, but by a lower voltage so that the doorbell button, which is necessarily placed outside and exposed to the elements, has a lower voltage that is not dangerous for man. The voltage is lowered by means of a small 220/12 volt transformer. This transformer is usually plugged into the electrical panel at home and is often assisted by a switch that can disconnect it from the grid. Doorbells usually malfunction in terms of the following main factors:
- Degradation or failure of the external button;
- Ring failure;
- Transformer failure;
- Accidental interruption or deterioration of the system
In the event of a malfunction, each of these elements must be checked in order to identify where the problem lies and then solve it.
Things you will need
- Screwdriver
- Vacuum
- Tester
Step 1
CLEAN THE EXTERNAL BUTTON
This may be a single button or inserted into a panel with other buttons for other housing units. In any case, screws secure it to the box containing the power cables. Moisture or even water can often enter this box or insects may enter it to make a nest. All these phenomena can lead to a malfunction. After disconnecting the mains switch of the electrical system at home, open the button panel and check the interior. Then vacuum it to remove any foreign objects. If any moisture is present, dry it completely.
Step 2
CHECK AND PERFORM MAINTENANCE ON THE BUTTON TERMINALS
Check the terminals into which the two cables are inserted. One or both of them may have been removed from the terminals. In any case, their screws must be loosened and the cables extracted. Then spray WD-40 Specialist Rapid-Drying Contact Cleaner on the terminals and cables of the doorbell, which removes condensation and quickly penetrates the hardest to reach areas, drying quickly and leaving no residue. It also restores correct electrical conductivity. Then reinsert the cables and tighten the terminals and check their operation before closing the button panel
Step 3
BUTTON OPERATION CHECK
If the doorbell still doesn’t work after carrying out the above, it may be that the button itself doesn’t work. You can check this by removing the cables from the terminals again and touching their ends together: if the bell rings the button needs to be replaced (be careful to perform this operation with some caution and respecting all safety measures). If the bell doesn’t ring, reassemble everything and check the transformer that supplies the doorbell with power.
Step 4
CHECK THE DOORBELL TRANSFORMER
After turning off the power to the system through the grid switch, access the transformer that supplies power to the doorbell, usually inserted in the electrical panel of the house, to check that the incoming cables (which bring the voltage to 220 volts) or those in output (12 volts) are securely fixed in the terminals. In any case, use some WD-40 Specialist Rapid-Drying Contact Cleaner as above. If the doorbell still doesn’t work, a tester must be used to check if the transformer produces the necessary voltage. However, this step must be carried out with the system live and should only be done by a qualified specialist. The specialist will use the tester to see if the transformer output has the required 12V. If not, the component must be replaced.
Step 5
RING CHECK
Once you’ve confirmed that the transformer is also working, if the doorbell still doesn’t ring, the bell is likely what’s broken. Also here, with the voltage disconnected, make sure that the cables connected to it are well inserted in the terminals. Again disconnect and reconnect them after applying some WD-40 Specialist Rapid-Drying Contact Cleaner. If this step doesn’t solve the problem, use the tester to check that the voltage reaches the bell itself when the doorbell button is pressed. If it does, the bell must be replaced.
Step 6
SYSTEM CHECK
If, on the other hand, the voltage is not present, then the problem is along the doorbell system. If this is the case, you’ll need a specialised technician, as it involves making disconnections and reconnections in junction boxes and carrying out tests using the tester with the system live. These are all operations which regulations prohibit a private user from carrying out.
Simply Done!
In conclusion, maintaining a functional doorbell involves a systematic approach to address common issues. From cleaning the external button to treating terminals with WD-40 Specialist Rapid-Drying Contact Cleaner, these simple steps can often restore smooth operation. However, if problems persist with the button, transformer, or bell, it's crucial to exercise caution and, when needed, seek the expertise of a qualified technician. A well-maintained doorbell not only ensures convenience but also enhances the overall safety and security of your home. With these troubleshooting tips and safety measures in mind, you can enjoy a reliable and efficient doorbell system for years to come.
Disclaimer
The uses shown and described for WD-40 Multi-Use Product were provided to WD-40 Company by the users themselves. These uses haven’t been tested by WD-40 Company and do not constitute a recommendation of suggestion for use by WD-40 Company. Common sense should be exercised whenever using WD-40 Company products. Always follow the instructions and take heed of any warnings printed on the packaging.
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