CVDR: Rectangular Constant Volume Damper

SubmittalSizes and Flow Rate TableAdjustment DeviceConstant Volume Slide Deck


The Constant Volume Rectangular Dampers are designed to provide a pressure-independent maximum air flow to a space. As velocity changes, the asymmetrical angled damper blade self-adjusts to maintain a maximum airflow. The system is adjusted at installations and can be adjusted over a wide range of desired flows. These units are installed in both the supply and exhaust side of commercial systems.


There are two ways to configure the CVDRs.  By themselves they provide flow up to a preset airflow.  Add a motor and now they can maintain one airflow when the motor is unenergized and a different higher set-point when the motor is energized.(Application Example: day/night — occupied/unoccupied)
This is new technology to the US. but has been employed in Europe for some time. The system has been designed to be robust with special maintenance-free bearings and a stabilizing piston to prevent vibrations. This allows the units to be installed in all but the harshest environment.


The CVDR Rectangular Constant Volume Dampers are available in about 31 discreet sizes.

If you need a motorized unit, choose one of the sizes in blue boxes below.

Use with flanged duct.
The CVDR is part of the Young Regulator Constant Volume Device product family.  Use them for a pressure-independent limit to maximum airflow.  Supply/Return/Exhaust/Fresh-Air Intake.