Wall-mount (jackshaft) garage door opener: fit check and install outline (spring work BLOCKED)

A wall-mount (jackshaft) opener bolts to the wall beside the door and turns the door's torsion shaft directly, so it needs very little headroom (about 3 in above the door) but needs side room at the end of the shaft (about 8 in). The door must already be balanced and in good shape: the opener does not lift a heavy door, the springs do. Spring, cable and drum adjustment is BLOCKED for this library; if the door is out of balance, a trained garage door tech fixes the springs before the opener goes on.

Cross-checked ~150 min moderateBrands: LiftMaster, Genie, All

Before you start

  • BLOCKED: do not adjust, wind, unwind or replace torsion or extension springs, cables or drums; refer to a trained garage door technician
  • Test door balance by hand before installing (door should stay put about halfway up); a door that slams down or flies up is a spring problem, not an opener problem
  • Disable or remove any manual door locks before the opener is operated
  • Install and align the safety reversing sensors; the opener must not close the door without them

Diagnostic steps

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Wall-mount (jackshaft) garage door opener: fit check and install outline (spring work BLOCKED) · OnCall Tech