Help with LiftMaster 8500 Specifications

[TestBill]

I am planning a pole barn. I plan on two 14x14 overhead doors, and I am researching the LiftMaster 8500 opener for those doors.

On page 2 of the LiftMaster 8500 Product Guide from the LiftMaster web site, it says, “Max. Door Size: 14 ft. High by 18 ft. Wide. Max 180 Sq. Ft.” I find this very confusing! I think what they are saying is the max height can be 14 ft and the max width can be 18 ft, but the combined Height x Width can NOT be greater than 180 Sq. Ft. Am I missing something or miss-reading the spec? So if I am correct, then per the spec, the 8500 opener is not suitable for a 14x14 ft. overhead door (196 Sq. Ft.).

After a very un-helpful phone call with their Tech Support (“It should work just fine”), I’m looking for any professional or personal experiences with the 8500 LiftMaster opener and 14x14 ft. doors. Am I misinterpreting or miss-reading the spec? Any help and insight is greatly appreciated.

Bill

 

[sneasle]

I have one of these on my 16ft double door, its only about 9, maybe 10ft tall. However, it is almost entirely made of wood, so it is very heavy.

I think the area rating is intended to help prevent folks from hooking it up to a door that may be too much overall weight for it to handle (even though the springs should minimize that impact). Otherwise, the only reason I can think of for the dimension being critical is if they are worried about a longer torsion bar being problematic when rotated from only one end.

Assuming you are using lighter weight aluminum doors, you're probably fine.

 

[gnpenning]

Yes, to the combined sqft.

The manufacturer specs it out for a reason. While the springs should be doing the work for lifting and controlling closing you still can over work the opener. Liftmaster makes different levels of openers to accommodate different door sizes. Match the opener to the door, don't put on a opener you know is undersized and hope it will work....

For future reference 8500w uses a different wall controller than the 8500. If you have done your homework you will understand why this is important.

 

[xyster101]

It is the total sqft of the door. I have 8x18 which is 144 sq/ft. My door is insulated with wind braces and very heavy. It has worked fine for 5 years. Ask liftmaster what is the next larger size and go with that.

 

[TestBill]

Thank you all for the inputs. I did receive a very nice e-mail from LiftMaster that clarified their spec sheet, and answered my questions:

"Relating to the dimensions of the door, the door must be no taller than 14' in height, 18' in width, and the area must not exceed 180 square feet. The maximum height is 14'. The maximum width is 18'.

For example, a door that is both 14' high AND 18' wide would be beyond the total square feet, so that wouldn't work. A door that's 7' tall and 18' wide would be OK. A door that's 14' tall and 10' wide would be OK.

A door that is 14' x 14' would exceed the total square footage, and would not be able to work."

Bill