Fasten The Door Bracket - Chamberlain Merlin Whisper Drive MT3850 Installation And Operating Instructions Manual

INSTALLATION STEP 6

Fasten the Door Bracket

Follow the instructions which apply to your door type as
illustrated below or on the following page.
SECTIONAL DOORS (A)
1. Centre the door bracket on the previously marked
vertical centreline used for the header bracket
installation.
NOTE: Door bracket must be installed with open end
up as illustrated below. If the bracket plate is used
observe the "TOP" indicator on the plate.
2. Position the top edge of the bracket 150-250mm below
the top edge of the door, OR directly below any
structural support across the top of the door.
3. Mark, drill holes and install as follows, depending on
your doors construction:
Metal or lightweight doors using a vertical angle iron
brace between the door panel support and the door
bracket:
• Drill 4.5mm fastening holes. Secure the door bracket
using the two self-threading screws (Figure 2A).
• Alternately, use two 8mm bolts, spring washers and
nuts (not provided) (Figure 2B).
Metal, insulated or lightweight factory reinforced
doors:
• Drill 4.5mm fastening holes. Secure the door bracket
using the self-threading screws (Figure 3).
Wood Doors:
• Use top and bottom or side to side door bracket holes.
Drill 8mm holes through the door and secure bracket
with 8mm carriage bolts, spring washers and nuts (not
provided) (Figure 4).
NOTE: The self-threading screws are not intended for
use on wood doors.
HARDWARE
Self-Threading Screw
Fiberglass, aluminum or lightweight steel garage doors WILL
REQUIRE reinforcement (not provided) BEFORE installation of
door bracket. Contact your door manufacturer for reinforcement
kit.
Header
Bracket
Door
Bracket
Location
Vertical
Centreline
of Garage
Door
Figure 1
Vertical
Reinforcement
Vertical
Centreline
of Garage Door
UP
Door
Bracket
Self-Threading
Figure 2A
Screw
Figure 3
Vertical
Centreline
of Garage Door
UP
Self-Threading
Screw
13
Vertical
Figure 2B
Reinforcement
(Not Provided)
Vertical
Centreline
of Garage Door
Bolt
Door
Bracket
Bracket Plate
Spring Washer
Inside Edge
of Door or
Reinforcement Board
Bolt
(Not Provided)
Vertical
Centreline
of Garage
Door
Spring Washer
Figure 4
Nut
UP
Nut