Chamberlain Security+ 3900PLD - Manual (Page 24)

24
Having a Problem? (Continued)
12. The operator won't operate due to power failure:
• Use the emergency release handle to disconnect the
door. The door can be opened and closed manually.
When power is restored, pull manual release a
second time.
• If a Standby Power Unit is connected, the operator
should be able to operate up to 20 times without
power.
13. Door loses limits.
• Collar not tightened securely. Tighten collar
(see Assembly Steps 1 and 2) and reprogram limits
(see Adjustment Step 1).
14. The operator moves when the door is in operation:
• Some minor movement is normal for this product. If it
is excessive the collar will wear prematurely.
• Check to make sure the torsion bar is not moving
left/right excessively.
• Check to make sure the torsion bar is not visibly
moving up and down as it rotates.
• Check that the operator is mounted at a right angle
to the jackshaft. If not, move the position of the
mounting bracket.