Describe when the sound happens

Note whether the noise begins at start-up, during a particular mode, in colder weather or only at certain times. A sound that occurs alongside an error message or reduced comfort is especially useful to report.

Identify the general location safely

You may be able to say whether the sound seems to come from the outdoor unit, indoor equipment, pipework area or controller. Do not remove panels or attempt to access internal components to investigate.

Know when to request a repair visit

A repeated, abrupt or unfamiliar sound should be assessed, particularly when it is paired with a performance change. A brief video or written note may help communicate the issue when you make the booking.