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It's crucial to perform safety obstruction tests to ensure the opener functions correctly and safely. For the close cycle test, first press the remote button to open the door. Place a piece of timber approximately 40mm high on the floor directly under the door's path. Then, close the door using the remote. The door should strike the timber and automatically reverse (re-open). For an additional close cycle test, open the door again and place the opener's carton (or a similar object) in the center of the doorway. Close the door; it should strike the carton and readily reverse. To test the open cycle, with the door in the closed position, press a remote button to start opening the door. When the door reaches approximately halfway, firmly grab the door's bottom rail with your hand (or place a suitable object that creates resistance). The door should stop its upward movement. If the door fails any of these tests (does not reverse when closing or stop when opening), the force may be excessive and needs adjusting. Immediately put the opener into manual mode via the manual release cord and operate the door by hand, then call for service.