Garage Door Safety Sensors

Here’s a scenario. You press the garage door button and the door doesn’t come down. No matter what you use, either the wall button or remote, the door comes down a bit and then goes back up. Then you figure out that if you hold the wall button down the door will close. Sound familiar? This is because of your garage door safety sensors.

The safety sensors, also known as the garage door photo eyes, are probably the best safety feature. The reason for this is it prevents the garage door from coming down on things like people or pets. Of course, they also prevent the door from hitting other objects such as cars, but people (especially children) and pets are the main concern.

Many Garage Door Photo Eyes Look Different But They All Work The Same

There are many different manufacturers of garage door openers. Some of the most common are Liftmaster, Chamberlain, and Genie. And they all have these photo eyes. And because of this, there are several different styles of safety sensors. But no matter what they look like, or how they are wired, they all work pretty much the same. The sensors are mounted on either side of the garage door track facing one another. Sensors should be mounted about 8 inches from the floor. The garage door safety sensors will consist of a sender and a receiver.

How They Work

Garage Door Photo Eye

On many brands, the garage door sensors will either have one amber light and one green light or two green lights. Generally, in most cases, the sending sensor will be amber. If not the sender will likely be green, but it will say sender on the back of the switch. 

Receiving Garage Door Safety Sensor

The receiving sensor will always be green. On some of the commercial overhead door openers, the photo eyes act differently. for example, the Liftmaster photo eye light will blink when they are interrupted, not go out.

Because the sending garage door photo eye sends the signal, the light on that photo-eye will always be illuminated. If it is not, that means that there is no power going to that sensor or the sensor needs to be replaced. Unlike the sender, the receiving photo-eye can go from being illuminated to being off. This is because the beam from the sender is not in alignment with the receiver or because the beam is interrupted. The receiving sensor could also need to be replaced but you need to check the sender first.

Some of the most common things that can be in the way of the beam are cobwebs, dirt and even the sun.

On some of the commercial overhead door openers, the photo eyes act differently. for example, the Liftmaster photo eye light will blink when they are interrupted, not go out.

When the beam is interrupted the door will stop and go back up. This is exactly what the garage door sensors are designed to do, make the garage door safe. But when you press the wall button or remote and the door doesn’t come down, this means that the photo eyes are not aligned. You can align the garage door sensors by adjusting the wing nut on the back. If your sensor doesn’t have this feature you will have to move the sensor perhaps. There are to many styles to explain so all you need to know is it’s just a matter of alignment.

It is never a good idea to put the garage door photo eyes up on the ceiling!

Some people put the sensors up and out of the way so they can never be interrupted. This is not highly recommended. The sensors are there for a reason. I know they can be annoying but I would suggest not to do this.

Replacing The Garage Door Safety Sensors

Photo eyes can sometimes need to be replaced. Inside the sensor their are components including a logic board that can become faulty. Most garage door openers will need to have the exact photo eyes that are specific to their brand. It is possible to replace safety sensors with a generic brand such as Chamberlain or Liftmaster. Chamberlain garage door safety sensors will work with most other garage door openers on the market. Liftmaster garage door safety sensors will also work with many brands of openers as well. If you need help finding where to buy garage door safety sensors, contact your local garage door opener dealer.

Leave a Comment