Most frequent questions and answers

Getting your garage door looked at by a professional at least once a year is a good idea. Most people do not realize when something is wrong because if the door goes up and down, they think everything is okay with it. A few things could be broken that only a professional would see and notice. This would include a hinge that is cracked, rollers that are worn out, cables that are coming apart, as well as opener parts wearing down. These are just a few of the things that our technicians look at when they inspect the garage door. Included is a link on some maintenance and safety checks that need to be done. https://www.fix.com/blog/garage-door-maintenance/

Before installing a garage door opener, you should ensure that the door operates easily manually. The rule of thumb is that if a ten year old child can lift the door with little or no effort, the door is well balanced. If the door is hard to lift, you should have a professional authorized dealer check the springs and other hardware on the door before installing an opener. Remember that the easier it is to open the door manually, the easier it will be for the garage door opener to open the door and that means the longer your garage door opener will last.

Each garage door opener has its advantages. The chain drive and belt drive are good in all applications, and the screw drive is best used on one piece doors that tilt rather than go up on a track. The screw drive runs a little slower than the other two garage door openers.
The belt drive is the quietest garage door opener and would be recommended for garages that have a room above them.
The chain drive is the garage door opener that we have been making the longest and offers dependable performance year after year. All of our garage door openers are very reliable and require virtually no maintenance.

The way the garage door opener comes out of the box it will open up to a 7 foot door. Our chain drive garage door openers can open up to 10 feet high with the proper extension kit. We have a kit for an 8 foot door and we have a rail assembly for 10 foot high doors. Both of these are optional equipment. Our screw drive and belt drive garage door openers can be extended to open an 8 foot high door.

Your garage door opener has two safety systems. The first and most apparent is the Safety Sensor System® which is located 4 to 6 inches above the garage floor on both sides of the door. To test the sensors, first open the door, then place a carton or an item that completely blocks the infrared beam of the sensors. When commanded to close, the door will not move more than an inch and the opener´s light bulb will flash for 5 seconds, equaling 10 flashes. Removal of the carton or item will allow normal operation. If the safety sensors become misaligned or obstructed, the garage door can be closed by pressing and holding the wall door control button until down travel is completed.
The second safety feature is a built-in automatic reverse system that will reverse upon striking an obstruction, provided the opener and door are installed and adjusted properly.
After adjusting the opener, always test the safety reverse system. We recommend repeating this test monthly.
Place a one inch board (or 2 x 4 laid flat) on the floor, centered under the garage door. Operate the door in the down direction. The door must reverse upon striking the board. If it does not, refer to your owner´s manual, call your local Liftmaster Authorized Dealer or speak to one of our technical service representatives by calling our S.O.S. HotLine® at 1-800-528-5880. Failure to pass the above test could result in serious injury or death.


All garage door openers manufactured after January 1, 1993 include the federally mandated Safety Sensor Reversing System®. These sensors are found 4 to 6 inches above the garage floor and protect the door opening with an invisible beam. If there is any problem with the safety sensors, the light bulb on the opener will flash 10 times and the garage door will not close unless constant pressure is applied to the wall button.
Both the sending and receiving sensors have a small LED light to help us align and troubleshoot them. The LED on the sending eye will glow regardless of alignment or obstruction. The LED on the receiving eye will go out when the beam is obstructed, and it will flicker if out of alignment.
The first step is to make sure that each sensor has a steady glowing LED light. If both lights are on, but one appears to be flickering very slightly, chances are the sensors are misaligned. To check for misalignment, first obstruct the beam of the sensors so that they cannot see each other. When the beam is blocked, the indicator light on one of the two sensors will temporarily go out. This is the receiving eye. Remove the obstruction so the light on the receiving eye comes back on. Then loosen the wingnut on the back of this sensor. Move the sensor around and make sure the green indicator light is bright and steady before you retighten the wingnut. This can take a few attempts before it is back in alignment.
If an indicator light is out on only one of the sensors, check for a possible loose wire. The sensor wires are attached to the white and black terminals on the back or side-panel of the overhead motor unit. Make sure the wires are securely connected to the terminals. If everything looks okay here, check the wires at the sensors. Move the wire around where it is connected in the back of the sensor. If the indicator light comes on, you have a short in the wires and/or sensor, and will have to replace the sensors.
If the problem seems to occur only during the daytime, check to make sure the receiving eye is not in direct sunlight. If this is the case, remount or adjust sensor back toward the side of the garage.
After any adjustment to the sensors, the opener itself or the door, test both reversing systems.
To test the safety sensors with the door open, press the remote control or pushbutton to close the door. Break the beam using your hand or a carton. The door should immediately reverse to a fully open position and the opener bulb will flash 10 times.
Next, place a one inch board (or 2 x 4 laid flat) on the floor, centered under the garage door. Operate the door in the down direction. The door must reverse on striking the board. If it does not, refer to your owner´s manual, call your local LiftMaster Authorized Dealer or speak to one of our technical service representatives by calling our S.O.S. HotLine® at 1-800-528-5880. Failure to pass the above tests could result in serious injury or death.


Have you ever wondered how leaves and water keeps getting in your garage? You may need a new bottom seal. The bottom seal is a great thing to have replaced every now and again. It stops things like water, leaves, bugs, and critters from getting into the garage. No one wants to go into their garage and see a snake just lying on the floor. The other purpose of the bottom seal is that it cushions the door as it goes down. It helps protect the bottom panel from being damaged by slamming hard on the ground.

Have you recently had your garage door painted? Is it making some popping noises now? One thing you want to check on is if the paint went in between the sections. This is a quite common thing. If the paint gets between the sections, it does not dry right. It stays a little sticky cause the sections to stick together. The only way to fix this is to clean between the sections and get that excess paint off. Just be careful to not scratch your newly painted door.

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