Doorbell - crossed/cut wires

WLSM

Hi,

I had my front door and frame replaced today, the fitter put my wired doorbell button on the new door frame as requested - the bell and transformer have since been making a humming noise and the transformer got very warm. I changed the push button to see if it was just stuck, this isn't the problem.
Any ideas on what is causing the humming - could the fitter have crossed wires or nicked them when screwing in the new frame, if so, should the bell just not work or short out instead of humming and working without me pressing it?

The wiring is two core bell wire, one coming from the transformer in the MCB, the other going to the bell/chime, each split within the pushbutton and screwed together to form the circuit.

hufpc8w3adnk65

Disconnect the power and carry out a continuity test on the cables

WLSM

Thanks MrMac

Steve

Does the bell still work?

Sounds like a short to me, in that case pressing the button would do nothing.

WLSM

Yip it works, it works too well unfortunately - going off by itself. I think the problem is that the circuit is unbroken even when the button is not pushed, I don't think some of the wires should be in the pushbutton itself, I will take two out, join them separately, so that only two wires are left in the button - one from the transformer, the other going to chime - so the circuit is broken and only continuous when the button is pushed.

DublinDilbert

Did he use a staple gun for the wires? Often the metal staples can pinch both wires as the insulation on the bell wire is quite soft.

WLSM

Don't think so, although there isn't any give in the wire so I'd say it is caught somewhere.

stoneill

Wires pinched by new door frame, insulation compromised and shorted.
That's why the humming and that's why there is no slack.