New Opener Reverses on Close: Limit vs Force vs Eye Commissioning Tree

Why this matters

A freshly installed opener that reverses every time it tries to close is a commissioning problem, not a defective unit. The three culprits, in the order you should evaluate them, are the photo-eye safety sensors, the down travel limit, and the close force setting. New installs reverse because one of these was not set, or was set wrong, during commissioning. Working them in sequence settles the door in minutes and, just as important, leaves the entrapment-protection system correctly armed instead of dialed out to make the door close. A door that closes by defeating its safety is not commissioned, it is unsafe.

Symptom presentation

• Door starts down and reverses immediately, opener lights flashing: photo-eye not made.
• Door travels most of the way down and reverses near the floor: down limit set short, or close force too low for seal compression.
• Door reverses on a slightly different spot each cycle: a mechanical resistance the force sensor is catching, or a marginal force setting.
• Door closes only with the wall button held (constant pressure): confirms an entrapment device is intercepting in normal mode.

Quick checks

1. Verify both photo-eye LEDs read steady (aligned and clear). A blinking or dark sensor reverses the door on every close. Align brackets, wipe lenses, confirm wiring polarity at the opener terminals.
2. Run the door and note where it reverses: immediately (eyes), near the floor (limit or force), or at varying spots (mechanical or marginal force).
3. Check the down travel limit against the true floor position. A limit set short tells the opener the door hit something before it reaches the floor.
4. Verify the door is mechanically balanced and travels smoothly by hand, so you are not setting force against a binding door.

Isolation tree

Branch 1, immediate reverse, eye LED not steady. Photo-eye fault, the most common new-install reverse. Realign the sensors until both LEDs are steady, clean the lenses, and correct any wiring swap at the opener. Confirm a clean close.

Branch 2, eyes steady, door reverses near the floor. Down travel limit. The limit is set above the floor, so the opener senses the door stopping early and reads it as an obstruction. Set the down limit to the point where the door just touches the floor with the bottom seal lightly compressed. Re-run.

Branch 3, eyes steady, limit at the floor, still reverses at the bottom. Close force too low. The opener reverses on the normal resistance of seal compression. Increase close force in small steps to the minimum that closes the door fully, then immediately verify the door still reverses on a 1.5-inch obstruction placed on the floor. If you cannot get both a reliable close and a reversal on the obstruction, the door is binding and needs mechanical correction, not more force.

Branch 4, reverses at varying spots. Mechanical resistance feeding the force sensor. The door binds in the track or the balance is off, so the opener catches the inconsistent load. Correct the track, rollers, or balance, then reset force.

Branch 5, closes only in constant-pressure mode. An entrapment device is intercepting in normal mode. Do not hand the customer a door that only closes on held pressure; resolve branches 1 to 4 so it closes safely in normal mode.

A door-balance prerequisite that new installs skip at their peril: an opener is a convenience device, not a lifting machine, and it can only be commissioned correctly on a door that is already balanced by its springs. If the door is heavy or unbalanced by hand with the opener disconnected, no amount of force and limit adjustment will produce a clean, safe close. The opener will either strain and stall (too little force) or slam the door (too much force) because it is fighting a counterbalance problem. Verify the door lifts smoothly and holds at mid-travel by hand before you set a single opener parameter. Commissioning a force setting against an unbalanced door bakes in either a nuisance reverse or an unsafe close.

A wiring-polarity note for the photo eyes on a fresh install: many sensor pairs are polarity-sensitive, and a sender or receiver wired backward at the opener terminals reverses the door on every close with a sensor LED that never goes steady. If realignment and clean lenses do not produce two steady LEDs, recheck that each sensor lead lands on the correct terminal before chasing alignment further.

Confirming diagnosis

The reverse location is the diagnosis path: immediate equals eyes, near-floor equals limit then force, varying equals mechanical. The commissioning is confirmed only when the door closes reliably in normal mode and reverses on a 1.5-inch obstruction laid on the floor, with the eyes armed. That obstruction test is the acceptance criterion for a new opener, not the close itself.

Remediation

• Photo eye: align to steady LEDs, clean lenses, correct wiring at the terminals.
• Down limit: set to the true floor with light seal compression.
• Close force: set to the reliable minimum, then verify obstruction reversal; never exceed the reversal threshold.
• Mechanical: correct track, rollers, and balance so force can be set low and the door still reverses.

Finish commissioning with the floor-obstruction reversal test and a manual emergency-release check, both passing.

References

• UL 325, Standard for Door, Drape, Gate, Louver, and Window Operators and Systems, entrapment-protection and reversal commissioning requirements.
• ANSI/DASMA 102, Specifications for Sectional Doors, operational criteria.
• DASMA Technical Data Sheet 353, Photoelectric Sensor and Reversing System Guidance.