An apartment intercom is a useful device, but it is no stranger to malfunctioning. However, they are often the least thought of appliance in an apartment. Most people only become aware of a problem when hearing a hum instead of a singsong chime, or when there is no sound whatsoever. Most of the time there is a quick fix and you will only need to follow a few simple steps to get to the root of the problem.
Step 1 - Assess the Buzzer
The first culprit of a faulty buzzer is the button itself. Inspect it for any wear and tear. This is a common problem if your buzzer is open to the elements or aggressive visitors. If your button appears to be in excellent shape, then remove the button's casing and check the state of its wires. Ensure the wires are attached properly to the button. You can handle dust accumulation at this stage by using a cloth drenched in rubbing alcohol or by just swabbing lens cleaner over the surfaces.
If the wires are well fastened, remove them and touch them together. Use the voltage meter to test for voltage before you go about this, to avoid getting shocked. If a chime emerges when you touch these wires together, then your problem lies with the switch and you have to get another one. If there is no sound or the sound of the chime echoes faintly, then the transformer is the problem.
Step 2 - Test the Transformer
The transformer in your system is an electrical component of the chime. It should be located near the chime. You can't work on it with the power turned on. You can, however, inspect the low voltage wires connected to it without disconnecting your electricity. These wires may simply be loose, in which case you only have to tighten them using a screwdriver to get your buzzer working gain.
If the wires are okay, use the digital multimeter to measure the voltage in the transformer's terminals. Set it at the 50VAC range. If you detect low voltage (below 6V) you need to replace the transformer.
Use electrical tape to mark the location of the transformer's wires. The wires on the circuit panel should match with those of the incoming transformer, that is, the black and white with the black and white and the green wire with the copper.
Step 3 - Check the Buzzer Wiring
This should be the final thing you check before you call in the experts. Inspect the wiring underneath the chime covering. Use the screwdriver to tighten any loose wiring.
These steps will help you diagnose and fix problems with an apartment intercom buzzer system.