The Young Regulator 9100 series (Model 9100-E) VAV ceiling diffusers are used to vary air volume from a wall-mounted thermostat. The diffusers are
designed to maintain coanda effect of discharge air along the ceiling. This provides a sustained discharge velocity throughout the volume range, and effectively
induces room air to achieve true VAV in both heating and cooling modes.
A direct-coupled actuator, installed outside the air stream on the neck of the diffuser, modulates to vary the supply air discharge opening.This varies the supply air volume in response to changes in the room temperature. Locating the actuator outside of the air stream makes servicing and troubleshooting convenient.
Operating diffusers from individual wall thermostats enables users to choose their own desired comfort level. This eliminates the problem of having to rely on inaccurate, slow acting, wax-type thermally powered actuators.