The boxes, KOOLAIR, model KMSR, are bypass terminal units used in single-duct, low-velocity systems where a volume control damper cannot or should not be used in the fan.
The KMSR receives constant air flow, supplies a part of this air to the room to be conditioned and reroutes the rest to the return duct. As a result, the equipment acts as a constant-volume unit, but the room to be conditioned receives variable flow air as needed.
Photos
Documentation
