pottorff BD Series User manual

Information is subject to change without notice or obligation. NOTE: Dimensions in parentheses ( ) are millimeters.
Backdraft Dampers IIBD (1/2) June 2014
model BD nd CBD
installation instructions
The following guidelines provide basic assembly and installation
instructions for models BD-150, BD-250, CBD-150 and CBD-250
backdraft dampers.
Carefully lift the dampers by their frames using multiple lifting points if
necessary. D n t apply excessive f rce t a single p int and
NEVER LIFT UNITS BY DAMPER BLADES OR BLADE LINKAGE.
Dampers larger than the maximum single section size are
manufactured and shipped for field assembly.
Assemble sections together using #10 TEK screws 2" (51) min. long as
shown.
Fig.1 St nd rd
Fr me (no fl nge)
Fig. 2 Front nd
Re r Fl nge
Gener l
Dampers
Locate all crates, boxes, cartons, etc.
Remove dampers from packaging, inspect for damage and
confirm quantities and sizes with packing list.
Notify your Pottorff representative immediately of any
shortages or shipping damage.
Inspect openings to ensure they are square and free from any
debris.
Verify that the damper will properly fit into the opening or into
the duct so that it can be installed square and will not be
racked.
1.
2.
3.
1.
2.
Openings
Prep r tion
POTTORFF ®5101 Blue Mound Road, Fort Worth, Texas 76106 www.pottorff.com
Verify that the backdraft damper is square, plumb and not
racked.
Backdraft damper is approximately 1/4" (6.4) smaller than
specified duct/opening.
Insert entire backdraft damper into duct/opening. Bottom of
damper frame must sit flat on bottom of duct/opening to
prevent twisting, sagging or uplifting.
Install units using mounting clips or angles [3/8" (9.5) high
(max.) x 1" (25) wide (min.) x 20 ga. (1.0) thick (min.)]. Arrange
clips against the perimeter of the front and back of the damper
frame, securing the clips to duct work.
Minimum of two fasteners per side to be used (top, bottom, left
and right jamb). Fasteners should be spaced 12" (305) on
center. (For alternate fastening method securing the frame
directly to the duct/opening, see Multiple Section Installation
details).
1.
2.
3.
4.
5.
Inst ll tion for D mpers with St nd rd Fr me (Fig. 1)
Verify that the backdraft damper is square, plumb and not
racked.
Inserted frame of backdraft damper is approximately 1/4" (6.4)
smaller than specified duct/opening size.
Make sure that the backdraft damper’s is flat and level when
being attached.
Secure backdraft damper’s flange using appropriate
fasteners.
1.
2.
3.
4.
D mpers with Front or Re r Fl nge (Fig.2)
Pre-drill fastener holes in the backdraft damper flange before
placing over opening to reduce twisting and binding.
It is recommended that a minimum of two fasteners per side
be used (top, bottom, left and right jamb). Fasteners should be
spaced 12" (305) on center.
Do not over tighten fasteners. ver tightening may damage or
twist the backdraft damper.
5.
6.
7.
Place first horizontal screw in between the top blade and the
second blade. See Detail 1. (Subsequent horizontal screws
should be spaced in between every other blade). See Detail 2.
Vertical screws should be placed a maximum distance of 8"
(203) from edge of frame and from center to center of each
screw. See Detail 3.
1.
2.
Inst ll tion for Multi-Sectioned D mpers (Fig. 3)
Fig. 3 Multi-Section D mpers
Detail 1
Detail 2
Detail 3

Information is subject to change without notice or obligation. NOTE: Dimensions in parentheses ( ) are millimeters.
Backdraft Dampers IIBD2 (2/2) June 2014
model BD nd CBD
installation instructions
POTTORFF ®5101 Blue Mound Road, Fort Worth, Texas 76106 www.pottorff.com
Make sure fasteners D N T interfere with linkage, axles or
blade linkage. See Fig 4 and Detail 4.
Dampers are designed to be self-supporting in the maximum
single section size. When dampers are installed in multiple
section assemblies, bracing may be required to support the
weight of the dampers and to ensure structural integrity
against system pressures.
3.
4.
Inst ll tion for Multi-Sectioned D mpers
Det il 4
(continued)
In order to maximize the counterweight effect, the counter-
weights should be adjusted away from the blade pivot point or
towards the blade pivot point. (Counterweights are to be field
adjusted.)
H riz ntal Airfl w and Vertical Airfl w Up:
Moving the counterweights away from the blade pivot point
will allow the blades to open with less air pressure. Make sure
that the blades still close when there is no pressure. If the
blades do not close then move the counterweights closer to
the blade pivot point. See Fig. 5.
Vertical Airfl w D wn:
Moving the counterweights closer to the blade pivot point will
allow the blades to open with less air pressure. Make sure that
the blades close when there is no pressure. If the blades do
not close when there is no air pressure then move the
counterweight away from the blade pivot point to allow the
blades to close. See Fig. 6.
1.
2.
3.
Counterweight Adjustment for CBD-150, CBD-250
Fig. 5 Horizont l Airflow nd Vertic l Airflow Up
Fig. 6 Vertic l Airflow Down
CUSTOMER IS TO:
D
Detail 4
CUSTOMER IS TO:
D
Fig. 4 Multi-Section D mper