I have recently purchased an old house with a wonderful door chime. But the button was broken, so I replaced it. But when you push the button, nothing happens unless you push it a second time, then the chime sounds. This is consistent every time. The button is lighted, so I know it is getting power. I have checked and replaced the wiring. Could this be a problem with the transformer?
How I tested mine first remove button leave cable connected and if you can get clear access to bell wire ends loop them across using a short length wire with ends stripped.
If the bell rings then its the button. Try gently bending the contacts closer. I did this on mine and it now works everytime.
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