Liftmaster 3800

[ViperJon]

I recently had two of these units installed in my new garage on 10 x 8' Clopay Coachman doors. Installed by a garage door guy. One works smooth as silk just as you would expect. The other, not so much. Seems to strain at first opening, starts slower and stutters on it's way up. When closing the last 6 inches, shudders and shakes but finally closes.

Checked out the obvious like the door itself. When manually operated the door seems smooth and has no descernible hangups or rough spots. It feels just like the other working door when manually opened. They are quite heavy but do operate smoothly. I have to assume it is something in the 3800 itself?

Any thoughts by anyone? Garage door guy says it's the unit and he is going to maybe get a replacement and try it. I know these units work basically by gravity on the closing operation could the torsion spring need to be adjusted? The reason I ask is that the are very heavy, my wife can barely lift them. I would think they would be easier to open since some people don't even use closers. The torsion springs are wound up to spec about 9 turns for a 10 x 8'. Would more (or less) spring tension help?

 

[kb2tha]

If not too much trouble, try swapping the units to see for yourself whether it is the unit or the door.

 

[joek]

It sounds as though the springs are not sized properly for the weight of your doors. You shouldn't have to expend significant amount of upward force to open them as the springs are designed to alleviate much of the door's weight. I would imagine the 3800 is having some difficulty with the weight. The first few seconds of opening and closing have the motor moving slower, which may explain why it only shudders during those times while it's getting the door moving (and stopping). However, it is interesting that your other 3800 is not having problems. Perhaps there are manufacturing tolerances in the motors. No idea.

One other idea: perhaps the collar on the bad 3800 is slipping?

 

[ViperJon]

I assume the springs are the correct ones for the doors, not sure how I can verify that? Doors are new but never saw any packaging etc as contractor installed.

I will check out any visible collar slipping, that is a thought.

 

[joek]

Someone else will have to chime in as to how to check the springs as I haven't dealt with installing new ones. Maybe they just need an extra turn, but you'd think the contractor would have done it properly...

 

[jstroede]

When you say that they are heavy, how do they act when you open the door a foot off the ground and let it go? How about 2 ft? How about half way? Do these doors have windows? If so what type?

John

 

[ViperJon]

When you say that they are heavy, how do they act when you open the door a foot off the ground and let it go? How about 2 ft? How about half way? Do these doors have windows? If so what type?

John

The one door that works smoothly will basically hold itself open in just about any position, even 6 inches off the ground. The door that is in question will fall from there, but hold itself open from about 24-30 inches. They both hold themselves steady at the half way point.

The torsion springs on both appear to be wound the same number of turns, between 8-9 which according to Clopay is right.

They are insulated doors with 12 lights in each upper panel.

 

[jstroede]

I'm a little confused because you stated that they were very heavy and that your wife could barely open them, yet you described a door that is pretty well balanced. Are the doors catching on the weather seal or door jamb that is making them hard to operate?

Are the windows insulated glass?

John

 

[ViperJon]

Hi John
They are heavy to get going from the fully closed position I guess is more accurate.
The doors weigh 210 lbs according to the serial number given to Clopay customer service with insulated glass. Not catching on anything noticable.

 

[StumpXJ]

Hi John
They are heavy to get going from the fully closed position I guess is more accurate.
The doors weigh 210 lbs according to the serial number given to Clopay customer service with insulated glass. Not catching on anything noticable.

If its balanced properly, it should only take a couple of fingers to open the door. The weight has nothing to do with it, since the springs make up for this. My door weighs 547 pounds, and all it takes is a stiff index finger to get it up or down from any position.

Nutshell? It sounds like you have a balance problem, or he didnt set the torque requirements for the one door. They are pre-set from the factory, but should be calibrated once it actually gets installed. Its part of the installation procedure. You can do it yourself if you have the instructions handy.

~ James

 

[rwhite692]

....Garage door guy says it's the unit and he is going to maybe get a replacement and try it....

Well, that sounds pretty non-committal / weak...Are you saying that the garage door guy has basically given up and left you hanging?

If it's not working to your satisfaction, why aren't you insisting that he make it right? Why take it upon yourself to try and solve the problem?

 

[V-10 Killer]

Remember when you're testing the opening/support force, the cables are lifting from the far left and right. If you're testing the load dead center on the door, it might be the same, as the cables will notice. Know what I mean? Check the action of the doors lifting from the far left and far right side, maybe one of your cables is a little too long/short and is binding a touch. Not overloaded just lifting at a very small side angle.
Also, is it possible the track might be adjusted too narrow somewhere, where you might be pinching the castors. Resistance from friction?

 

[ViperJon]

Thanks guys going to give it a real going over this weekend to check all gaps and fitment with the tips from here. I'm positive something is binding it but not readily apparent.

 

[dmeadow]

I think this is what V-10 is saying, but just to reiterate--

You picking up the door in the middle is a little different than the Liftmaster turning the end of the jackshaft. If either end of the jackshaft is loose the door may be racking when the Liftmaster torques it. My experience with the Liftmaster is that it is very sensitive to binding in the door. Once properly adjusted, though, it is great.

On the other hand, those doors should not be a problem for the Liftmaster and it does sound like they are not balanced properly. Good luck!

 

[ViperJon]

Thanks again I will check it out.

OT to V-10 Killer...I have a V-10 you can't kill.....

 

[V-10 Killer]

Thanks again I will check it out.

OT to V-10 Killer...I have a V-10 you can't kill.....

Probably, but you can't argue that smacktalking sure is fun

 

[jstroede]

One other thing I will tell you. Doors like you have are a PAIN. The top section with the insulated glass has a higher percentage of the door weight of the other sections. One of two things occurs in this case. Number 1, if you spring the door for the entire weight of the door with the windows, the door will balance well off the floor, but will begin to take off once the top section kicks over into the horizontal track. Number 2, if you spring the door so and ignore the additional weight of the glass in the top section, it will be very hard to get the door moving, but once the door is about a foot off the door, it starts to balance pretty well. Somewhere in the middle is usually what you shoot for, but obviously that is a compromise. For doors such as yours, I generally add on half of the additional window weight to calculate the springs.

Operating the door from either end on a torsion setup should not really make a difference, unless something is drastically wrong. Now on an extension spring door, that is a different matter. If that were the case, using jackshaft openers on 20' wide doors and larger wouldn't work very well.

If I had to guess, I would say that maybe the one door might need another quarter turn on the spring, and that it might be binding a little at some point. Check your jambs and trim for any rub marks.

John

 

[cowboyjosh]

Hey John, question.

Not to hijack this discussion, but I don't want to start a new topic for a stupid question.

On CHI garage doors, I have insulated glass tops much like the Clopay's in question on this discussion, can I tint the windows or will it crack the insulated glass or warp the rest of the pane? CHI distributor couldn't give me a yes or no, calls to CHI directly directed me to the distributor who I called initially.

 

[jstroede]

You should be able to tint it with just standard window film no problem. I see no reason why it would it crack or warp? Are you thinking of something other than window film?

John

 

[cowboyjosh]

You should be able to tint it with just standard window film no problem. I see no reason why it would it crack or warp? Are you thinking of something other than window film?

John

nope, just window tint, nothing as dark as auto tint, just something to darken up the glass. I didn't know if GD glass was like low e type double pane glass, where if you tint the glass you can get a heat fracture.

Thanks.