Aiphone GT-1C7W Operation Manual page 22

Operation during receiving a call or communication
Releasing the door
While being called or communicating, tap
Activating an external unit such as
lightning equipment
While being called or communicating, tap
Activating doctor call
.
To enable doctor call.
1
Tap .
2
Tap YES .
.
fl
To disable doctor call.
Tap .
fi
fi
YES