29-01-15, 07:29 PM
Got to be an external noise source.
What time does your heating programmer shut down for the night?
A few years ago I had a similar problem and narrowed it down to when the heating was switching on and again when switching off. Changing the controller did the trick so must of had a dirty contact inside.
What time does your heating programmer shut down for the night?
A few years ago I had a similar problem and narrowed it down to when the heating was switching on and again when switching off. Changing the controller did the trick so must of had a dirty contact inside.