the buzing noise
reset the travel of distance of the motors
All
Too short of transmitter distance.
The transmitter battery is near power off.
The wall button works well, but the transmitter doesn’t work.
No transmitter learning. Transmitter battery is power off.
The door can open, but fails to close.
Photo beam function is enable, but the photo beam has not been installed or photo beam is obstructed.
After setting open and close positions, the motor does not work
The screws of fixing the hall components are loose. Program mistakes.
The motor does not work.
The socket is not well connected, or fuse is blown.
The chain is noisy.
The chain is too loose.