Garage Door does not stay up in manual mode
I have a 16' aluminum garage door with tension springs.
The door is very difficult to open and it does not stay up. If I let the door go while lifting it up, it will drop and crash.
I checked out the springs and doesn't look like either of them are broken. I also looked at the pulley wheels and cables on each side and they look fine.
All track wheels look fine.
It seems as though the springs are not working properly.
Is there any way to determine if this is the case?