American Made. World Proven.
Model RT-150 Installation & Operation Instructions
Roto-Twist
®
cable actuated damper drive system.
Receipt Inspection
Check material received against packing list. Claims resulting from factory errors must
be made within 2 weeks after receipt of goods.
Installation
1. Radial dampers are furnished as one piece; however, make sure cable end is secure in
damper pivot coupling prior to installing.
2. Secure damper in position in duct. Screw or rivet through bearing bracket side
pieces-minimum 1 screw per side. Do not rack or distort damper. Dampers are ¼”
undersized from nominal dimensions. Position damper to allow best cable run,
avoiding tight turns, while keeping adjustment end in its preferred accessible position.
Keep adjustment end of cable within 5” of accessible opening if possible. Alternately
cables may be left hanging out of ceiling upon installation of air outlet and slipped
back in after balancing.
3. Secure adjustment end as follows. Nylon clamp may be positioned anywhere along
cable length to keep adjustment end in accessible position. Do not over tighten.
Operation
Dampers may be adjusted by applying a quality ¼” nut driver or hex socket to the male
square adjustment end of the cable. Once set, dampers will hold their settings at all
velocities up through the design limits. Operator nut drivers, with 6” shaft length, may be
purchased from the manufacturer. Optional screwdrivers tipped units are adjusted with a
thin blade screwdriver.
Maintenance
Properly installed Roto-Twist® dampers require no maintenance of any kind.
Toll free: 800.585.7686 +1.708.552.4040 | Chicago, IL USA www.metairtech.com
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