Electric shower buzzing?

[Burnerman]

Not mine, I hasten to add....all I did was to replace the failed 45 amp pull switch on the ceiling.
However, with the switch on, the shower unit emits a low buzz or hum (transformer like) even though its not heating or producing any water. It did this before I arrived on the scene! Sorry I don't know the make of the shower but I'll find out if its relevant.
Any comments, gentlemen?
Cheers and good evening
John

 

[seco services]

Make/model will help id fault better depending if it has a pcb or not.
Relays are prone to buzzing if it has a pcb. they get stuck in the on position.

 

[Burnerman]

Aha thats worth knowing! I'll get back if I need to (a real hovel, that place so I don't want to rush)
I appreciate your time, Seco - cheers!
John