Outdoor Unit Clicks: Fan Blade Warped by Afternoon Heat

Clicking that is faint in the morning, clearly audible by mid-afternoon, and gone again by evening as the ledge cools. Cooling never falters through any of it. The ledge faces west and takes direct sun for several hours.

A motor fault clicks at whatever hour it is asked to run, because nothing about a worn bearing knows the time. Plastic does. A blade that has taken years of direct sun holds a warp, and heat expands that warp further until it reaches something. So the question stops being what is worn and becomes what moves when it gets hot.

Direct afternoon sun on a west-facing ledge heats a plastic blade well past ambient, day after day, and repeated heat cycling leaves a permanent set in one edge. Cool, that warp clears the housing with room to spare. Warm, the plastic expands a little further and the edge catches on every rotation until the ledge cools again. The clicking follows the sun rather than the runtime, and that is a signature nothing mechanical produces, because nothing mechanical gets better as the day ends.

Replace the blade and confirm clearance across the temperature range rather than at whatever temperature the visit happens to fall on. No motor work follows, since it tested clean throughout. Worth raising separately is shade for the ledge, because the sun that warped one blade is still there and will work on the next one at exactly the same rate.