dpb wrote:
...
Well, they're not needed if the door is balanced properly...they're
mostly for advertising.
....
By that I'm meaning the one on the solid wood door I bought for the
folks was purchased in the early 80's long before there was such an
emphasis on the size--it's a 1/2hp and has worked and continues to
function for nearly 30 years now.

I'd say that demonstrates one doesn't have to have a large opener just
because the door is heavy if the load springs are correctly matched to
the door.

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