Chamberlain 3255M 1/2 HP, 3255-2M 1/2 HP, 3245M 1/3 HP owner manual ONE-PIECE Doors

ONE-PIECE DOORS

Please read and comply with the warnings and reinforcement instructions on the previous page. They apply to one-piece doors also.

•Center the door bracket on the top of the door, in line with the header bracket as shown. Mark either the left and right, or the top and bottom holes.

•Metal Doors: Drill 3/16" pilot holes and fasten the bracket with the 1/4"-14x5/8" self-threading screws provided.

•Wood Doors: Drill 5/16" holes and use 5/16"x2" carriage bolts, lock washers and nuts (not provided) or 5/16"x1-1/2" lag screws (not provided) depending on your installation needs.

NOTE: The door bracket may be installed on the top edge of the door if required for your installation. (Refer to the dotted line optional placement drawing.)

HARDWARE SHOWN

ACTUAL SIZE

Self-Threading Screw 1/4"-14x5/8"

Header Wall

2x4 Support

Header

Bracket

Door

Bracket

Optional

Placement

of Door

Bracket

Vertical

Centerline of

Garage Door

Finished Ceiling

HORIZONTAL AND VERTICAL REINFORCEMENT IS NEEDED FOR LIGHTWEIGHT GARAGE DOORS (FIBERGLASS, ALUMINUM, STEEL, DOORS WITH GLASS PANEL, ETC.). (NOT PROVIDED)

For a door with no exposed framing, or for the optional installation, use lag screws 5/16"x1-1/2" (Not Provided) to fasten door bracket.

	Self-Threading
	Screw
Door	1/4"-14x5/8"
	Top of Door
Bracket
	(Inside
	Garage)
	Top Edge
	of Door
	Optional
	Placement
	METAL DOOR
Nut	Lock
5/16"-18
	Washer
	5/16"
Door	Top of Door
Bracket	(Inside
	Garage)
	Top Edge
	of Door
	Optional
	Placement
	Carriage Bolt
	5/16"x2"
	(Not Provided)
	WOOD DOOR

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