Garage door opener installation

[Xfaxman]

Looks interesting , so does it rely on the door weight to actually close the door?

Yep, it rotates the shaft the other direction to close. The door is held up by the cables wrapped around the cable drums and as it rotates, the weight of the door pulls it down. The overhead track has to be higher at the back (not level), to get it started going down.

 

[s219]

Looks interesting , so does it rely on the door weight to actually close the door?

Yes, pretty much. All it really does is counteract whatever difference exists between the spring tension and the torque from the door weight -- basically, it sees the same resistance your arm would, but at the jackshaft axle in a rotational/torque sense rather than a linear force sense. Kind of an interesting way to think about it.

So when going down, it basically allows slack on the side cable drums and the door starts going down taking up the slack. There is a cable-tension sensor (simple switch with an arm and roller that touches the cable) that stops and reverses the motor if any excessive slack is detected, for instance if the door hits an obstacle on the way down. That will prevent the drums from unwinding and causing all he!! from breaking loose (happened to me on an older door with a different style opener once, and it was a train wreck when the door became cockeyed in the tracks).

 

[bigtiller]

With gravity closing it, when the door is down, can it be opened by hand or is there a way to lock the door?

 

[ultrarunner]

I didn't go with hormann openers only because the install was from friend and didn't recommend them, can't really remember why. The doors have been great. I really love like my liftmaster openers with battery back. Soft start/stop belt and drive makes for a really quiet operation.

The Hormann openers are very compact, super quiet and have soft start.

So far it's been 12 years with light use..

The doors are also very quiet and I like the safety features.

 

[Xfaxman]

With gravity closing it, when the door is down, can it be opened by hand or is there a way to lock the door?

The opener would prevent the shaft from rotating, so no, not by hand, fork lift, yes.

 

[countrybumpkin]

Thanks, I've never really paid attention to these opens and the way they closed. I will be giving these a close look in the near future, we are fixing to build a 3 car garage and I'll have 3 doors in my shop. I really like the clear over head.

 

[Xfaxman]

Thanks, I've never really paid attention to these opens and the way they closed. I will be giving these a close look in the near future, we are fixing to build a 3 car garage and I'll have 3 doors in my shop. I really like the clear over head.

The one that we had (different brand) would sense the motor current and stop if the door hit anything going up or down.

I tested it by standing under it. When it contacted my shoulder, it reversed and shut off. I felt just a slight amount of pressure.

 

[murphy1244]

Yep, it rotates the shaft the other direction to close. The door is held up by the cables wrapped around the cable drums and as it rotates, the weight of the door pulls it down. The overhead track has to be higher at the back (not level), to get it started going down.

I hear these jam up a lot cause there is very little weight to go down when it starts.

 

[Xfaxman]

I hear these jam up a lot cause there is very little weight to go down when it starts.

After I raised the back of the track, no problem with the 8x16 insulated door.

As you can see, there is no clearance for a conventional opener.

 

[s219]

With gravity closing it, when the door is down, can it be opened by hand or is there a way to lock the door?

As noted, the weight of the door prevents casual attempts to lift, but the 8500 opener also comes with an electric deadbolt lock that mounts to the track and slides a pin through. It is to be placed just above a wheel, so that the door can't roll up.