Chamberlain 248735 3/4 HP Garage Door Opener User Manual


 
33
HAVING A PROBLEM?
1. My door will not close and the light bulbs blink on
my motor unit: The safety reversing sensor must be
connected and aligned correctly before the garage door
opener will move in the down direction.
Verify the safety sensors are properly installed, aligned
and free of any obstructions. Refer to Installation Step
10: Install The Protector System
®
.
Check diagnostic LED for flashes on the motor unit
then refer to the Diagnostic Chart on the following
page.
2. My remotes will not activate the door:
Verify your Motion Detecting Door Control is not
blinking. If it is blinking, deactivate the Lock Mode
following the instructions for Using the Motion
Detecting Door Control.
Reprogram remotes following the programming
instructions. Refer to Programming.
If remote will still not activate your door, check
diagnostic LED for flashes on motor unit then refer to
Diagnostic Chart on the following page.
3. My door reverses for no apparent reason: Repeat
safety reverse test after adjustments to force or travel
limits. The need for occasional adjustment for the force
and limit settings is normal. Weather conditions in
particular can affect door travel.
Manually check door for balance or any binding
problems.
Refer to Adjustment Step 2, Adjust the Force.
4. My door reverses for no apparent reason after fully
closing and touching the floor: Repeat safety reverse
test after adjustments to force or travel limits. The need
for occasional adjustment for the force and limit settings
is normal. Weather conditions in particular can affect
door travel.
Refer to Adjustment Step 1, Adjust the UP and DOWN
Travel Limits. Decrease down travel by turning down
limit adjustment screw clockwise.
5. My lights will not turn off when door is open:
The garage door opener is equipped with a security
light feature. This feature activates the light on when
the safety sensor beam has been obstructed. Refer to
Operation section; Using the Wall Mounted Door
Control, Light Feature.
Receiving Eye Safety Reversing
Sensor (Green Indicator Light)
Sending Eye Safety Reversing
Sensor (Amber Indicator Light)
6. My motor unit hums briefly:
First verify that the trolley is against the stop bolt.
Release the door from the opener by pulling the
Emergency Release Rope.
Manually bring the door to a closed position.
Loosen the chain by adjusting the outer nut 4 to 5
turns. This relieves the tension.
Run the motor unit from the remote control or door
control. The trolley should travel towards the door
and stop. If the trolley re-engages with the door, pull
the Emergency Release Rope to disengage.
Decrease the UP travel by turning the UP Travel
adjustment screw 2 full turns away from the arrow.
Re-tighten the outer nut so the chain is a 1/4" (6 mm)
above the base of the rail. (When the door is
reconnected and closed, the chain will sag. This is
normal.)
If the trolley does not move away from the bolt,
repeat the steps above.
Safety Reversing Sensor
Bell Wire
"Learn"
Button
LED or
Diagnostic
LED
KG
1
3
9
7
5
KG
1
3
9
7
5