Chamberlain 3850 - Manual (Page 24)

Black Button
Purple Button
Push Purple button
twice to enter
unit into
Force
Adjustment Mode
Indicator Light
24
ADJUSTMENT STEP 2
Setting the Force
The force setting button is located on the left panel of
the motor unit. The force setting measures the amount
of force required to open and close the door.
1. Locate the purple button on the left panel of the motor
unit (Figure 1).
2. Push the purple button twice to enter the opener into
Force Adjustment Mode (Figure 2). The LED (Indicator
Light) will flash quickly.
3. Push the remote control or control console (Figure 3).
The door will travel to the DOWN (close) position. Push
the remote control or control console again, the door
will travel to the UP (open) position. Push the remote
control or control console a third time to send the door
to the DOWN (close) position.
The LED (Indicator Light) will stop flashing when the force
has been learned.
The opener has learned the forces required to open and
close your door.
The door must travel through a complete cycle, UP and
DOWN, in order for the force to be set properly. If the
opener cannot open and close your door fully, inspect your
door to insure that it is balanced properly and is not
sticking or binding. See page 3, “Preparing your garage
door.”
Without a properly installed safety reversal system, persons
(particularly small children) could be SERIOUSLY INJURED or
KILLED by a closing garage door.
• Too much force on garage door will interfere with proper
operation of safety reversal system.
• NEVER use force adjustments to compensate for a binding or
sticking garage door.
• After ANY adjustments are made, the safety reversal system
MUST be tested. Door MUST reverse on contact with 1-1/2"
(3.8 cm) high object (or 2x4 laid flat) on floor.
Indicator
Light
Black Button
Purple Button
Figure 2
Figure 1
or
LOC K
LIGH T
Figure 3
WARNING
CAUTION WARNING
WARNING