We bought a new construction house about 5 years ago. A Chamberlain LiftMaster 1/2hp Professional was installed. Never had any issues until yesterday.

It will start to open, and then stop abruptly after about a foot. When I hit the button, it will return to the closed position. I can manually open it, and I don't feel any binding. I checked the track and chain, and everything appears to be in place. When I run it without the door attached, it runs fine, and goes to the start and stop position. The sensors are working perfectly, when I run it without the door attached, and you cross the beam, it does it's typical "stop immediately, and flash the light routine. It does not do this when I have the door attached, but it stops immediately.

I don't know anything about garage door openers, but I'm guessing Chamberlain is a "builder quality" unit.

Any ideas?

This message has been edited. Last edited by: ASKSmith,

I had a similar issue last year. It was a sensor issue. In the morning the sun would hit one of the sensors just right where it throw it off. I figured this out by creating shade at that entry point into the garage.

I had the company come out and replace the sensors and re-position them slightly. Problem solved.

Maybe swap the two sensors and see if that helps?

Check and see if it will open while giving it and "assist" by hand lifting the bottom of the door.

If it does, check the "up lifting" adjustment and see if that fixes it.

Over time, with wear in the rollers and track, loss of lubrication and grime, can lead to this symptom.

It does the exact same thing either during the daylight or dark.

I also tried to assist it, and it just stops. When the door is completely up, and I "relock" the door back onto the chain drive, it will lower. But when I hit the UP button, it goes about a foot and just stops. Hit the button again, and it will lower back to the adjusted height.

When mine does that it is usually because someone, has bumped one of the sensors and they are no longer lined up with each other. Try feeling of them to see if one is looser than the other and if so, move the loose one around until it looks lines up and try again. It usually takes a few trys to get it right.

Chamberlin is a good company and makes a ton of openers under a lot of brand names. I believe they are a quality company.

Is there too much slack in the chain, i.e. is it drooping?

Sensor(s) out of alignment and/or sun on sensor(s). Once I figured it out and corrected it, it worked as normal. You might also check the wiring to ensure the wire(s) are not broken.

quote:

Originally posted by ASKSmith:
I'm guessing Chamberlain is a "builder quality" unit.

They may make a cheaper line but they are pretty much one of if not the best go to brands out there.

quote:

Originally posted by GaryBF:
Is there too much slack in the chain, i.e. is it drooping?

Yes, it is drooping. I thought about that as well. My wife parked in the garage, so I was unable to get a ladder and check out how to adjust it. This was after I found out my 13y/o son manually lifted the door. LOL.

Mine was doing the same a few months ago so I gave the sensors a little adjustment and haven't had a problem since.

If the chain is slacking or drooping, then you have a worn bearing in the drive shaft. As the bearing wears, it disintegrates and the dust from it falls and lands in the grease on the gear, making it worse. I will find the Youtube video and post soon. I had this exact problem. New parts kit cost $20 and took me less than an hour to install. Works perfectly now and I had never touched a garage door repair before this.

Link to parts kit here too.

https://www.youtube.com/watch?v=K-7zCoZPy_s

The wisdom of SigForum never fails to impress.

Thanks Rick Lee, I will give that a shot, as that is exactly what my door is doing.

Does your opener have a cable tension sensor? That's what caused issues with mine. I switched it to the other side to solve the issue.

FIXED!!!

Rick Lee, I didn't have to order the parts, yet. I just ended up tightening the chain tension. It's been working fine now. It's much more quiet as well.

I hope it really is fixed, but....

I've had the same issues come and go on my home units. It has ALWAYS ended up being either a sensor that was brushed/kicked/moved inadvertently, or the sun reflecting off something and making the sensor lose it's mind.

Sometimes I would tighten the chain, etc, and it would act like it was fixed, then do it again later. In my case, we have a 3 car garage, and each car has its own door. This allows me to compare the sensor light colors and position, and I usually find that the color is red (vs green if it's making a proper circuit). The other thing I have seen is that someone will place an item (paint can, car with different shape fender, etc) in a position that the sun catches the reflected light on the item and shines it into the sensor.

Like I said, hope it's fixed.