Chamberlain LiftMaster LM70EVFF Assembly And Operating Instructions Manual page 13

9. Motor hums and runs very briefly, but does not function:
• Garage door springs are defective� Close the door and disconnect
from the opener by pulling on the handle of the carriage (manual
release)� Open and close door manually� If the door is properly balan-
ced, it is held at each point of the doorway by the door springs alone�
If this is not the case, contact your service centre�
• If this problem appears during the first use, the door may be locked.
Deactivate door lock�
• Release opener from the door and try without door. If the door is fine,
reprogramme operating force and stretch of way�
10. Opener works only in one direction:
• Door springs may be defective or the door is stiff in one direction.
• If the door is fine, re-programme operating power and stretch of way
of the opener�
11. The belt rattles on the rail:
• Adjust the belt tension� The cause is usually a very tight chain/belt�
The spring on the clamping device of the rail must not be compres-
sed completely�
• The door runs unevenly and makes the drive vibrate� Improve door
run�
12. Opener will not start due to power failure:
• Disconnect from the opener by pulling on the handle on the carriage
(manual release)� The door can now be manually opened and closed�
If the opener is re-activated, the carriage also gets re-connected�
• If installed, the carriage is detached from the drive in case of power
failure by an external emergency release from outside the garage�
13. Door reverses after the force was programmed:
• See if the rail bends� The opener requires a lot of power to move the
door� Repair or install door correctly�
• Door is very heavy or in poor condition� Call a specialist�
14. Rail bends on the opener:
• Door is heavy, very heavy, stiff or in poor condition. Call a specialist.
• A swing of the rail while moving is a sign of an unevenly functioning
door with constantly changing power requirements� Call specialist,
possibly lubricate door� An additional suspension on the rail can be a
remedy�
14. Rail bends on the opener:
• Door is heavy, very heavy, stiff or in poor condition. Call a specialist.
• A swing of the rail while moving is a sign of an unevenly functioning
door with constantly changing power requirements� Call specialist,
possibly lubricate door� An additional suspension on the rail can be a
remedy�
15. The opener „runs" (audible turning of motor) but the carriage
does not move:
• The carriage is released from the opener�
• In a new installation: During the assembly of motor and rail, the
pre-assembled adapter sleeve between the motor shaft and the rail
was not installed� This sleeve is pre-assembled at factory, but can be
removed� Standing behind the opener it can be observed whether the
gearwheel turns in the rail or just the motor�
• In a new installation: The belt has come off from the gearwheel in the
rail� Standing behind the opener, you can see the gearwheel�
• After years of use: Is the release defective or continuously disenga-
ged?
• After years of use: The sleeve between rail and motor or the motor
control gear is defective�
16. The door releases by itself from the carriage and stops:
• An external release that has been installed during a power failure
should be checked whether it stretches and releases during the ope-
ning of the door� Watch the mechanism and reset if necessary�
• The handle of the release mechanism should not get caught in other
items�
17. Setting the Force
• The force setting button is located behind the cover at the operators
backside� The force setting regulates the amount of power required
to open and close the door�
1� Open cover on the backside of the opener� Locate the yellow
round button (2)�
2� Push the yellow round button (2) twice to enter unit into Force
Adjustment Mode� The LED (3) (indicator light) and the UP button
will flash. Push UP button. The operator will travel to the UP position
learning the required amount of force� Once the UP limit is reached
the LED and the DOWN button a start to flash. Push DOWN button.
The operator will travel to the DOWN position learning the required
amount of force�
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