<p>Here Typical vav terminal unit including control valve , union , hot water coil , ball or gate type valve , plenum air inlet , calibrated balancing valve ,pressure ports for flow balancing , support rods from roof structure with vibration isolation , round duct for cold supply air inlet , hot water coil associate piping and fitting apply to heating and cooling terminals only HWR , HWS erminal units, commonly referred to as VAV boxes, are <strong>used to control the volume and, sometimes, the temperature of air entering a designated space</strong>. There are a few different types of terminal units used in today's developments: single duct, parallel fan-powered, and series fan-powered. It is basically a calibrated air damper with an automatic actuator. The VAV terminal unit is connected to either a local or a central control system. These terminal units, commonly referred to as VAV boxes, are <strong>used to control the volume and, sometimes, the temperature of air entering a designated space</strong>. There are a few different types of terminal units used in today's developments: single duct, parallel fan-powered, and series fan-powered. for more details download this file .</p>