Diagnosis
The ChainMax 1000 doesn't have a physical switch for travel direction. The direction (which side the trolley starts from) is set by software during installation and can be reversed via a programming sequence.
How to Fix It
To reverse the travel direction, you'll use the wall control panel. 1) Make sure the door is fully closed. 2) On the wall console, press and hold the square door button (not the light button) for about 10-15 seconds, until the console light blinks. 3) Release the button. 4) Immediately press and hold the same door button again. The door will now move. 5) As soon as it starts moving, release the button. The door will stop. This sets the new "fully closed" position. 6) Now press and hold the door button once more. The door will move in the opposite direction. Let it go all the way until it stops (or hits the physical stop you've set). Release the button. This sets the new open limit.
If That Didn't Work
If the opener just beeps or doesn't respond, you might have started with the door in the wrong position. The door must start fully closed for this procedure to work correctly.
Heads Up
Reversing direction like this also resets your travel limits. You will absolutely need to reset the UP and DOWN limit settings afterwards, or the door won't stop in the right places.