The majority of garage doors in American households use the same operating principles.
A large door that’s separated into flexible panels moves up and down on rollers installed in a track system. The garage door opener, usually mounted in the center of the garage provides the actual pulling power to bring the garage door up or down.
However, without the weigh-reducing assistance of the springs that typically run across the length of the garage door opening, the opener motor wouldn’t be able to pull up the significantly heavy weight of a garage door.

Safety features
Since the garage door is typically the largest moving object within a home, modern garage door systems also feature several key safety features that protect home occupants, children and pets from death or injury due to accidental misuse or malfunction.
Auto reverse
The first safety feature is an automatic reversal system within the opener itself. If the door is closing and an obstruction or solid object is detected – usually anything that slows or stops the door’s normal operation – the door should automatically stop and return to the open position. The U.S Consumer Product Safety Commission has required a reversing safety feature on all new garage door openers manufactured since 1991.
Because garage door springs and openers can degrade over time, it’s important to occasionally test this safety feature. With the garage door open, place a solid object such as a 2-by-4 board or a cinder block where the door will close – never test any safety feature using your or another person’s body. With the board or block in place, press the close button. If working properly, the garage door should close on the obstruction and immediately reverse the closing operation when it comes in contact with it.
Motion detection
Another key safety feature to prevent entrapment from garage doors is the “electric eye” sensor system found on many more modern garage door systems. Sensors placed on either side of the garage door’s track system about 4 to 6 inches off the ground transmit an infrared beam of light during a door’s closing operation. Should anything break the beam during the closing operation – including adults, pets or other objects – the opener should automatically stop and reverse the closing operation.
Manual release
One of the last safety features on a garage door system is the manual release mechanism. Designed to disengage the garage door from the opening system should entrapment, a power outage or other malfunction occur, the manual release mechanism is most commonly found on the track that runs from opener to the garage door. It’s usually a bright red handle that should hang no higher than 6 feet off the ground.
Should an object or individual become trapped, or if a malfunction occurs, pulling on the handle will allow the user to manually lift the door up or down. If a garage door is good working order, the spring system that runs across the top of the door opening should provide enough assistance so an average adult can lift the door with relatively little effort.
All three of these safety features should be occasionally tested to ensure they’re in working order. If any of the features fail to work as designed, call a garage door professional to repair or replace them.




Doors that open or close partially might have a blocked or misaligned sensor and can be easily fixed.
Angie's List can help connect you with a highly rated and recommended garage door expert in your area.
This steel door is durable, well insulated and eco-friendly. | Photo courtesy of Richard Lines
Comments
remote missing
remote missing, If I buy a door remote door opener can you set it just by looking at the door opener unit ? It’s a old sears model.
door opener
remote missing, If I buy a door remote door opener can you set it just by looking at the door opener unit ? It’s a old sears model.