Garage door auto-reverse explained

Auto-reverse is the feature that makes a closing garage door go back up when it meets something in its path. It exists to protect children, pets and property. This guide explains how it works, how often to test it, and what a failed test means.

A garage door is heavy, and a closing door can trap a person. In 1991 CPSC announced a joint program with industry to address child entrapment, and reported that since 1982 it had received reports of 48 children, aged two to 14, who died after being trapped under automatic garage doors. A later CPSC publication gave a count of about 73 children between the ages of 2 and 14 since March 1982.

Congress required openers made for sale in the United States on or after January 1, 1991 to have entrapment protection. Openers made on or after January 1, 1993 must also have one of two further protections, described below. CPSC advised owners at the time that openers without automatic reversal should be replaced immediately.

This is consumer guidance and history. Your own opener's manual gives the exact procedure and settings for your model.

Auto-reverse is not one device. Two systems work together.

CPSC's 1992 rule announcement says openers manufactured on or after January 1, 1993 must include either an external entrapment protection device, such as an electric eye or door edge sensor, or a constant contact control button. A constant contact button must be held until the door fully closes, and releasing it early reverses the door. The remote cannot close the door under that option.

The reversal test is a standard homeowner check, and both CPSC and Chamberlain describe it. Only do it if the door moves normally, is on its track and shows no sign of a broken spring or cable. If anything looks wrong, skip to the next section.

1. Clear people and pets from the garage and the doorway.
2. Fully open the door.
3. Lay a 2x4 flat on the floor, centered in the door's path. Chamberlain describes a one-inch board or a 2x4 laid flat, and says the door must reverse on contact with an object 1-1/2 inches high.
4. Close the door with the remote or wall control and stand clear, with the door in view.
5. The door should reverse when it touches the board. Chamberlain says the door must reverse when striking the obstruction.
6. Remove the board and run the door through a few full cycles. Chamberlain suggests three or four.
7. Repeat the test each month and after any adjustment to the opener. Chamberlain says it should be done monthly and after any adjustment.

The photo eyes need their own check. How to test them differs by make and model, so check your model's manual.

If the door does not reverse, treat that as a safety fault, not a minor setting. CPSC advises that if the door fails to reverse on the 2x4, owners should disengage the opener until it is adjusted, repaired or replaced. Chamberlain says that if the door stops on the board without reversing, it may not be traveling far enough in the down direction. It then points owners to the opener's travel and force adjustment guides, and says to call a trained door systems technician if the opener still fails after repeated attempts.

• The door fails the board test, or stops on it instead of reversing.
• The door reverses on its own with nothing in the way.
• You have to adjust force or travel settings more than once to pass the test.
• The photo eyes do not stop the door when you break the beam.
• The door is crooked, off its track, very heavy or noisy. Do not run it. See when a garage door is unsafe to use.

Our technicians inspect the door, the opener and the sensors, and confirm the cause before making changes. See garage door opener repair and safety sensor repair.

Sources point to a few causes, and a technician checks each in turn.

• Travel limits. Chamberlain ties a door that stops on the board to down travel that is not set far enough.
• Sensors. A misaligned, blocked or disconnected photo eye can keep a door from closing, or from reacting as designed.
• An unbalanced door. If springs are worn or broken, the door can be heavy for the opener. Clopay describes a balance check done by disconnecting the opener and lifting the door about halfway. A balanced door stays put, and an imbalance is a job for a professional. See how a garage door stays balanced.
• An old opener. CPSC advised in 1991 that openers without automatic reversal be replaced. See repair or replace an opener.

Auto-reverse is a backup, not a babysitter. CPSC and DASMA both advise teaching children about garage door danger, keeping remotes out of their reach and mounting the wall button out of reach. DASMA says at least 5 feet from the floor. Read more in garage door safety with children and pets. Regular testing is also part of the annual maintenance checklist.

• Garage Door Opener Repair
• Garage Door Safety Sensor Repair

• CPSC: Garage door opener safety
• Chamberlain: How do I test the safety reversal system
• CPSC: Safety Commission publishes final rules for automatic garage door openers
• CPSC: Government and industry move to reduce garage door opener child entrapment deaths
• DASMA: Garage door safety