Every six months
Every six months you ought to thoroughly inspect the entire system. Look for loose screws and bolts, worn metal, dirt on the tracks, check the springs, levers, hinges, and cables and notice any abnormalities.When there is a problem test the electric openers itself by pulling the release cord when it is in closed position to disconnect the Roll up Garage Door from the opening mechanism. Then attempt to open it manually. If it opens smoothly and correctly than it can be determined that there is a problem with the opener and it must be repaired or replaced.If the doors are difficult to raise when disconnected to the opener the springs may be the culprit. If the springs are in perfect condition it should be able to stay half open on its own.