Andrew Southard
By Elimination. Turn off all your electrical trips or pull all your fuses. See if the noise goes. One by one replace the fuses or turn the trips on, noting if the humming noise comes back. Identify which circuit causing the noise. If it's a lighting circuit, switch on/off each light to see if the noise changes. If a power circuit, unplug devices and note any change in the noise. Common things to look out for. Heating elements, dimmer switches, fluorescent lights, certain low voltage lights and transformers, fans. If there is a loose electrical connection the noise is accompanied by a smell of hot insulation, as the resistance caused will produce heat. If in any doubt isolate the circuit an call a qualified electrician. It may also be a component in a boiler or vibrating pipe. Isolate the boiler and see if the noise stops. If in doubt call a qualified plumber. Hope this helps? Cheers Andrew
