Bypass Type VAV: Model – PAC-BVAV-1L / 1M

1L – Top bypass for low-pressure applications; 1M – Side bypass for medium pressure applications.
PACVENT Bypass type VAV is a single duct pressure-dependent air terminal unit, designed to use with constant volume for low and medium pressure air handling systems at low prime cost. Units may be used with cooling and heating/cooling systems. Required temperature can be achieved by supplying only enough conditioned air to the space to satisfy room thermostat demand, and excess air is diverted (bypassed) directly to the return air ceiling plenum for free or ducted return. Airflow to each occupied zone will vary on thermostat demand, from full flow to shut-off or to a mechanically set minimum air volume. A bypass box, commonly referred to also as a “dump box” or “relief type” handles a constant supply of primary Air through its inlet and uses a diverting damper to bypass part of the supply air into the plenum return. The damper is directly controlled by the room thermostat in the occupied space to provide the volume of air required to meet the thermal demand. Bypass terminals can be added to a single-zone constant volume system to provide zoning without the energy waste of a conventional reheat system, providing low first cost with minimum fan controls. Although variable volume to the space in operation, total airflow of the fan remains constant, so the fan power and associated energy cost are not reduced. Its most frequent application is on small systems.