Hello,

I recently added a switch to a light. The box also housed the doorbell transformer. When I turned the circuit breaker back on, the switch and light work fine, but now the doorbell transformer buzzes noticeably. The doorbell still works. I checked the connections and wiring for shorts, but ultimately disconnected the transformer, leaving my doorbell disabled. I should mention that the original box was so old that I was unable to get any of the ko's out. I wound up just putting everything into a new box, but things did a little roughed up while I was trying to pop out a ko.

Is the transformer bad? Should I just get a wireless doorbell to replace this one?

Thanks for the help.

 

Is it possible that you are noticing a vibration from a transformer that is not mounted securely?

 

The new box I installed caused the transformer to not quite fit well, as it was up against the floor joist. So that could be it.

I did, however, try hooking it up dangling in the air to see if it was vibrational. Same sound dangling in the air. Does that mean it's not vibration? Or do i need to get it mounted securely in a new box?

Many thanks for your response.

 

Those transformers typically mount ouside the box and have a built-in clamp that uses a knockout in the metal box.

For the small cost I might try to change the transformer.

 

Thanks for the help. Turned out my transformer was for an intercom system and had two black load wires. I had wired it as if one of the black wires was a neutral.

I bought a new transformer anyway with a white and black wire and installed it tightly in its own box. Works fine. No buzzing.

Thanks for the advice.