Sears 139.53971SRT, 139.53960SRT HOW and When to Adjust the Forces, Test the Down close force

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 one-inch obstruction. See Adjustment Step 3, page 30.

If the door is hard to hold or doesn't reverse,

DECREASE the DOWN (close) force by turning the control counterclockwise. Make smag

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'tflashing, 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'topen at least 5 feet, INCREASE UP (Open) force by turning the controlclockwise. Make small adjustments until door opens completely.Readjust the UP limit if necessary.After each adjustment, runthe opener througha complete travel cycle.

Without a properly installedsafetyreversalsystem, persons(particularly smallchildren) could be SERIOUSLYINJUREDor KILLEDby a closinggarage door.

•Too muchforceon garagedoor will interferewith properoperation of safetyreversalsystem.

•NEVERincreaseforce beyondminimum amount requiredto closegaragedoor.

•NEVERuse forceadjustmentsto compensatefor a bindingor sticking garagedoor.

•If one control (forceor travellimits) is adjusted,the othercontrol mayalso needadjustment.

•After anyadjustmentsare made,the safetyreversal systemMUSTbetested. Door MUSTreverseon

contactwith one-inch highobject (or 2x4 laid fiat) on floor.

Force Adjustment Control

Back panel

Adjustment Label

29