Step 2 adjust the force, Adjustment step 2, Adjust the force – Chamberlain 1215EM FS2 User Manual
Page 30

ADJUSTMENT STEP 2
Adjust the Force
Force adjustment controls are located on the back panel 
of the motor unit. Force adjustment settings regulate the 
amount of power required to open and close the door.
If the forces are set too light, door travel may be 
interrupted by nuisance reversals in the down direction 
and stops in the up direction. Weather conditions can 
affect the door movement, so occasional adjustment may 
be needed.
The maximum force adjustment range is about 3/4 of a 
complete turn. Do not force controls beyond that 
point. Turn force adjustment controls with a screwdriver.
NOTE: If anything interferes with the door’s upward travel, 
it will stop. If anything interferes with the door’s downward 
travel (including binding or unbalanced doors), it will 
reverse.
HOW AND WHEN TO ADJUST THE FORCES
1. Test the DOWN (close) force
•
Grasp the door bottom when the door is about halfway 
through DOWN (close) travel. The door should reverse. 
Reversal halfway through down travel does not 
guarantee reversal on a 38 mm obstruction. See 
Adjustment Step 3.
If the door is hard to hold or doesn't reverse,
DECREASE the DOWN (close) force by turning 
the control counterclockwise. Make small adjustments 
until the door reverses normally. After each adjustment, 
run the opener through a complete cycle.
•
If the door reverses during the down (close) cycle 
and the opener lights aren't flashing, INCREASE 
DOWN (close) force by turning the control clockwise. 
Make small adjustments until the door completes a close 
cycle. After each adjustment, run the opener through a 
complete travel cycle. Do not increase the force beyond 
the minimum amount required to close the door.
2. Test the UP (open) force
•
Grasp the door bottom when the door is about halfway 
through UP (open) travel. The door should stop. If the 
door is hard to hold or doesn't stop, DECREASE UP 
(open) force by turning the control counterclockwise. 
Make small adjustments until the door stops easily and 
opens fully. After each adjustment, run the opener 
through a complete travel cycle.
•
If the door doesn’t open at least 1.5 m,
 INCREASE UP (open) force by turning the control 
clockwise. Make small adjustments until door opens 
completely. Readjust the UP limit if necessary. After 
each adjustment, run the opener through a complete 
travel cycle.
30
Force
Adjustment
Controls
Back Panel
FORCE ADJUSTMENT LABEL
KG
KG
1
3
9
7
5
1
3
9
7
5
KG
KG
Antenna
Open Force
Close Force
Without a properly installed safety reversal system, persons 
(particularly small children) could be SERIOUSLY INJURED or 
KILLED by a closing door or gate.
• Too much force on garage door will interfere with proper 
operation of safety reversal system.
• NEVER increase force beyond minimum amount required to
close garage door.
• NEVER use force adjustments to compensate for a binding or
sticking garage door.
• If one control (force or travel limits) is adjusted, the other
control may also need adjustment.
• After ANY adjustments are made, the safety reversal system
MUST be tested. Door MUST reverse on contact with 38 mm 
obstacle on the floor.
