Since 1978, Acutherm Therma-Fuser Systems have proven to be the simple, reliable, and economical solution for individual temperature control. Each Therma-Fuser diffuser is an independent zone of VAV control with built-in room thermostats and modulating dampers for varying the air volume. The dampers are continuously adjusting to vary the volume of air flow (warm or cold) into the room, in response to room temperature. Unlike fixed opening diffusers, which dump cold air on occupants at low volumes, the variable air opening within all Therma-Fuser diffuser models creates high air velocity even at lower supply volumes. This maintains the Coanda effect where high velocity air hugs an adjacent surface, holding cold air up to the ceiling and prevents dumping.