If your opener hums but the door doesn't move, that's usually a stripped gear or a dead capacitor - common on units that are 10+ years old in this heat. If the light blinks and the door reverses before it closes, check your photo-eyes first; heat and vibration knock them out of alignment on these newer installs more than people expect. A remote that's stopped working while the wall button still opens the door points to the board's receiver circuit, not the remote battery. And if the opener runs but is noticeably louder or slower than it used to be, that's often a belt stretching out or a motor starting to go - not yet an emergency, but worth a call before it quits on you on a 100-degree afternoon with the door stuck halfway up.