The Young Regulator Model 4000 Ventgard damper is a rectangular, opposed-blade, energy efficient exhaust damper. It generates substantial savings by stopping the exhaust of conditioned air by rooftop ventilators from hotels, condos, high-rise bathrooms, kitchens and conference rooms when they are unoccupied. It is installed behind the exhaust grill and is ideal for both new construction and retrofits.
The damper is wired in-line with the light switch. In occupied rooms (light switch On), the damper opens to permit the rooftop exhaust fan to pull out stale air. The damper remains open for approximately 15 minutes after the light switch is turned off.
In unoccupied rooms (light switch – OFF), the damper is closed to prevent the rooftop exhaust fan from pulling conditioned air out of the space. This reduces energy use and saves operating expenses.
For relief a bypass loop of outdoor air can be installed. Optionally a variable speed fan or motor VFD could be used.