The afternoon sun beat down like a hammer on the tin roof of the old farmhouse. Inside, Lena wiped a bead of sweat from her brow and aimed the remote at the Midea AC unit mounted high on the wall. She pressed the power button. Nothing. She pressed it again, harder. The display remained as dark as a dead star.

Nothing happened.

The air conditioner, which she affectionately called "The Sentinel" for its reliable hum during three sweltering summers, was now a mute, white block of frustration.

"Tom," she said, "forget the plug. Your unit needs a factory reset via the remote."