TROX VARYCONTROL® VAV terminal boxes type TVZ and TVZD were developed for the control of supply air flow, especially in variable volume systems. A special feature of these types is the outstanding acoustic qualities that show themselves to the best advantage in buildings with critical comfort criteria. The boxes meet the hygiene requirements of VDI 6022.

The mechanical components and electronic components which are factory fitted, form the controls package. Each box is set up to the required flow rates and is subjected to an aerodynamic function test.

The boxes contain an averaging differential pressure sensor for air flow measurement, a control damper and an integral sound attenuator for reducing the air regenerated noise.

The control damper blade with plastic seal when closed complies with the air tightness requirements of DIN EN 1751.

There is a circular spigot connection on the fan (high pressure) end with a rectangular flange connection on the room (low pressure) end.

The boxes with additional acoustic cladding and/or an TS secondary silencer are suitable for very demanding acoustic requirements.

The flow rate control is a closed circuit system with external power supply. The pressure transducer, controller and actuator are selected to meet the controls requirements and operational conditions. The TROX VAV boxes can be supplied with control components from any reputable manufacturer to suit the project specification

Characteristics

• Electronic flow rate control
• Suitable for supply air
• Flow rate range (depending on manufacturer and type of controller) approx. 10 :1
• Very close control accuracy for the flow rate settings, even with upstream bend at R = 1 D. Please ensure the most favourable aerodynamic configuration of ductwork is used
• Differential pressure range 20 to 1500 Pa
• Full shut-off from duct work system
• Control damper closed blade airtightness to DIN EN 1751, class 4 (nominal size 125, class 3)
• Baffle plates are fitted after the control damper for optimum acoustic and aerodynamic performance
• Integral sound attenuator with at least 26 dB insertion loss at 250 Hz
• Horizontal or vertical installation (when using diaphragm pressure transducers, install according to label on the box)
• Factory set up or programming of flow rate. This includes aerodynamic function test of each box using a dedicated test rig. Data covering set up is given on a test label attached to each box