LiftMaster 8550 8550 Manual - Page 8

Installation 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). HARDWARE H3 (2) Lag Screw 5/16"-9x1-5/8" OPTION A WALL INSTALLATION 2.1A 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). 2.2A Mark the vertical set of bracket holes (do not use the holes designated for ceiling mount). Drill 3/16" pilot holes and fasten the bracket securely to a structural support with the hardware provided (H3). OPTION B CEILING INSTALLATION 2.1B Extend the vertical centerline onto the ceiling as shown. 2.2B 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. 2.3B Mark the side holes. Drill 3/16" pilot holes and fasten bracket securely to a structural support with the hardware provided (H3). Wall Mount The nail hole is for positioning only. You must use lag screws to mount the header bracket. 2x4 Structural Support CEILING MOUNT ONLY (Header Wall) Header Bracket UP Optional Mounting Holes Horizontal Line Highest Point of Garage Door Travel Ceiling Mounting Holes Header Bracket 6" (15 cm) Maximum CEILING MOUNT ONLY UP Door Spring The nail hole is for positioning only. You must use lag screws to mount the header bracket. (Garage Door) Vertical Centerline of Garage Door H3 Door Spring (Garage Door) (Finished Ceiling) Vertical Centerline of Garage Door H3 (Header Wall) 8