Chamberlain 3850PC Determine the Header Bracket Location, INSTALLATION STEP, NOTE:, approximately 1/2" (1 cm).), the wall upside down if necessary, to gain

INSTALLATION STEP 1

Determine the Header Bracket Location

To prevent possible SERIOUS INJURY or DEATH:

•Header bracket MUST be RIGIDLY fastened to structural support on header wall or ceiling, otherwise garage door might not reverse when required. DO NOT install header bracket over drywall.

•Concrete anchors MUST be used if mounting header bracket or 2x4 into masonry.

•NEVER try to loosen, move or adjust garage door, springs, cables, pulleys, brackets, or their hardware, ALL of which are under EXTREME tension.

•ALWAYS call a trained door systems technician if garage door binds, sticks or is out of balance. An unbalanced garage door might not reverse when required.

Installation procedures vary according to garage door types. Follow the instructions which apply to your door.

1. Close the door and mark the inside vertical centerline of

the garage door.

2. Extend the line onto the header wall above the door.

You can fasten the header bracket within 4 feet

(1.22 m) of the left or right of the door center only if

a torsion spring or center bearing plate is in the

way; or you can attach it to the ceiling (see page 9)

when clearance is minimal. (It may be mounted on

the wall upside down if necessary, to gain

approximately 1/2" (1 cm).)

If you need to install the header bracket on a 2x4

(on wall or ceiling), use lag screws (not provided)

to securely fasten the 2x4 to structural supports as

shown here and on page 9.

3. Open your door to the highest point of travel as shown.

Draw an intersecting horizontal line on the header wall

Unfinished

Ceiling

Header Wall

Vertical Centerline

of Garage Door

Level (optional)

Header Wall

2" (5 cm) Track

Highest Point

of Travel

Door

Door

OPTIONAL

CEILING

MOUNT

FOR

HEADER

BRACKET

2x4

2x4

Structural

Supports

Header Wall

2" (5 cm) Track

Highest Point

of Travel

above the high point:
•	2" (5 cm) above the high point for sectional door and
	one-piece door with track.
•	8" (20 cm) above the high point for one-piece door
	without track.

This height will provide travel clearance for the top edge of the door.

NOTE: If the total number of inches exceeds the height available in your garage, use the maximum height possible, or refer to page 9 for ceiling installation.

Sectional door with curved track One-piece door with horizontal track

		Header Wall
	Header Wall	8" (20 cm)
	8" (20 cm)
	Highest	Highest
Door		Point
	Point	of Travel
	of Travel	Door
Jamb
Hardware
		Pivot
One-piece door without track:		One-piece door without track:
jamb hardware		pivot hardware

8