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Timer-to-close and app/remote closing: when it is allowed (UL 325) and what to check before enabling it

Closing a garage door when nobody is watching is allowed under UL 325 only on sectional (and horizontal sliding) doors, with photo eyes or another monitored secondary entrapment device, and only after a warning: a sound and flashing light for at least five seconds before the door moves. One-piece and swing doors must not be set to close unattended. If the close is interrupted, the opener retries and then locks out further unattended closing.

Cross-checked ~20 min easyBrands: LiftMaster, Chamberlain, Genie, All UL 325 openers

Before you start

Do not enable timer-to-close or app closing on a one-piece (tilt-up) or swing door.
Run the reversal and photo-eye tests before turning on unattended closing; the door must reverse on both.
Only use a closing accessory or app that the opener maker lists as compatible/certified; third-party add-ons may not provide the required warning.

Diagnostic steps

Unlock all 4 steps with expected values

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