Unit Rocks on Hillside Ledge: Brackets Never Tightened

Rattling from the outdoor unit on a hillside ledge, present for as long as anybody can recall. The equipment itself is relatively young. Cooling has always been perfectly satisfactory throughout.

Asking when a noise started is a routine question with an unusual answer here, and that answer redirects the whole visit. Wear produces a change, and a change has a date attached to it. Something present from the first day is not wear at all; it is simply how the installation was left. That points at the work rather than the equipment, and support fixings are the commonest thing to be run up finger-tight and never finished off.

Bracket fixings are often run up by hand as the unit is manoeuvred into position. They are meant to be tightened properly once it is settled. On an awkward site that final pass is easy to skip, and nothing about the finished installation shows it was missed. The unit then sits on a support able to move from its very first day, so it has always made the sound it makes now.

The fixings are tightened properly and the bracket checked for movement under load. What is worth carrying forward is the question, not the repair itself. Ask whether it has ever been quiet. An answer of no moves the whole investigation from the machine to the handover, and that saves opening equipment with nothing wrong inside it.