Addict,
The main function of a weir door is so that the skimmer sucks in the surface water, bringing with it all the floating stuff.. Without the door, there is not really any "skimming" action..
The door should bob up and down with the water level. The door is held in place at the bottom, generally from a pin on either side.. If the door comes off the pins it can get jammed. Also if it is a generic replacement door, held in place by spring pins, they can move sideways and get jammed that way.
No way anyone here can tell for sure. I have never heard of a "bad" weir door.. Most that don't work have broken pins or have come loose or moved out of position if a replacement door.
If this were my pool I would reinstall the door and try to manually move it up and down and see if I could figure out what is making it stick up..
Thanks,
Jim R. aka.. "HoneyBunny"
