Replacing Door Opener

[Viper Luna]

I'm replacing a broken opener with a new one. The installation instructions say that if the door is higher than 7 feet I need an extension. My door is not higher than 7 but already has an extension from the previous opener. I measured the rail on the old Chamberlain and it's exactly the same length as the new Chamberlain. Do I need to remove the extension to install this the way the manual says to or can I use it and just follow the extension instructions?

 

[RyanDan]

I would think the opener would work just fine with the extension. I am assuming its talking about the guide and chain, if so you'll just have the opener further away from where the door stops. On a bigger door the open needs to be further from the wall so the door doesnt open into it. Just my thoughts.

 

[Viper Luna]

I'm not the sharpest tool in the box but it seems logical that the opener would still do its job the same way with or without the extension, but I wanted to make sure before I rip it down

 

[kbs2244]

" exactly the same length"
It is called "form. fit and function"

If fits, looks the same, it will function
Go for it

 

[Innovate1]

The way I read you post you are saying the DOOR has an existing extension. The extension for a taller door goes on the rail of the OPENER. Almost sounds like two different things. Some pictures would help. In any case if the openers are the same length you should be fine. Putting in an opener with an extension when it isn't needed works fine. There is a switch that is positioned to set the up position of the door and that will compensate for any difference as long as the opener is good for at least the height of the door.

 

[Hot Rod Grampa]

When the door is closed you want the J bar to be plumb vertical. Sometimes en extension is used on the J bar to compensate for the opener being higher than the normal range. I believe “ normal “ is to have the rail about 3” higher than the torsion tube. If the old system worked, the new one should also.

 

[lml999]

If the old system worked, the new one should also.

The OP did state the the old opener is broken. Perhaps the extension contributed to a higher load on the opener and caused it to burn out prematurely.

I haven't worked out the physics, so I can't state conclusively. And of course, if I did work out the physics, it would be complete hogwash.

Just sayin'