the water heater switch in my house has started making a buzzing sound now & then, whats's the problem? It's a 20amp DP isolation switch with a neon, not the timer, I have not checked yet but perhaps a loose wire, is it safe or does it need replacing?
Probably a loose cable, it should catch fire soon then you will know for sure it was a loose cable. Seriously though if in doubt change it is a good policy
making a buzzing sound now & then, whats's the problem? These switches were designed to make a buzzing sound. If you want other sounds you must download them from the web via USB/Bluetooth. You can obtain quite merry little polyphonic tunes apparently.