HKEK wrote:
I am installing electric openers on two new (sectional) garage doors.
The doors are top-of-the-line models from Overhead Door, dealer
installed. I have always understood that the weight of the garage
doors must be counter balanced by the springs. Makes sense.


That's why you need a 1/2hp motor.

If the springs exactly and perfectly balanced the load, you could lift the
door with the motor from your bedside clock.