Chamberlain C400 Owner's Manual page 13

Installation
STEP 2 Install the Header Bracket
You can attach the header bracket either to the wall above the garage door, or to the ceiling. Follow the instructions
which will work best for your particular requirements. Do not install the header bracket over drywall. If installing
into masonry, use concrete anchors (not provided).
Lag Screw 5/16"-9x1-5/8"
OPTION A - WALL INSTALLATION
1. Center the bracket on the vertical centerline with the bottom edge of the bracket on the horizontal line as
shown (with the arrow pointing toward the ceiling).
2. Mark the vertical set of bracket holes. Drill 3/16" pilot holes and fasten the bracket securely to a structural
support with the hardware provided.
OPTION B - CEILING INSTALLATION
1. Extend the vertical centerline onto the ceiling as shown.
2. Center the bracket on the vertical mark, no more than 6" (15 cm) from the wall. Make sure the arrow is
pointing away from the wall. The bracket can be mounted flush against the ceiling when clearance is
minimal.
3. Mark the side holes. Drill 3/16" pilot holes and fasten bracket securely to a structural support with the
hardware provided.
HARDWARE
WALL INSTALLATION
Structural
Wall Mounting
Support
Holes
UP
Horizontal
Highest Point
Optional Mounting of Garage
Holes Door Travel
CEILING INSTALLATION
Header
Bracket
6" (15 cm)
Maximum
Ceiling Mounting
Holes
Door Spring
UP
13
Header Wall
2x4
Header
Bracket
Line
Garage Door
Finished Ceiling
Garage Door
Vertical
Centerline of
Garage Door
Lag
Screw
Door
Spring
Vertical
Centerline of
Garage Door
Lag Screw
Header Wall