Installation Guidelines
Weight and Counterweight Adjustment
SERIES 7600 WT WEIGHT ADJUSTMENT:
ADJUST RESISTANCE TO OPEN
- The angle of the external weight crankarm and the number of weights per crankarm will be preset at the factory, to maximize the resistance to opening.
- If installation conditions require field-adjustment to accelerate or delay the opening of the blades, loosen the external crankarm screws and rotate the external weight crankarm(s) until the desired angle is achieved.
- Retighten the external crankarm screws.
- Further adjustment can be made by increasing or reducing the number of weights on the external crankarm(s), or by sliding the weights up or down along the crankarm(s).
SERIES 7600 CWA COUNTERWEIGHT ADJUSTMENT:
ACCELERATE OR DELAY OPENING
- The angle of the external counterweight crankarm and the number of weights per crankarm will be preset at the factory, to minimize the airflow necessary to open the backdraft damper blades.
- If installation conditions require field-adjustment to accelerate or delay the opening of the blades, loosen the external crankarm screws and rotate the external counterweight crankarm(s) until the desired angle is achieved.
- Retighten the external crankarm screws.
- Further adjustment can be made by increasing or reducing the number of weights on the external crankarm(s), or by sliding the weights up or down along the crankarm(s).