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Round constant air volume dampers
  • Constant
  • Velocity range – 2m/s to 8m/s
  • Mounting – duct
  • Options – lipseal, double skin insulation, secondary attenuator
  • Round, supply / exhaust ducts, manual / actuator adjustment

WRM volume flow rate controllers for air conditioning and ventilation systems, suitable for vertical and horizontal installation in supply and exhaust ducts. The casing and control mechanism are made of galvanised sheet steel. The centrally supported damper blade, which controls the volume flow rate, has a stainless steel bearing axis in special bushings.

Adjustment device with rotary pointer, scale and lock for the volume flow rate set point and can be adjusted manually or by actuator.

WRM volume flow controllers are mechanical controllers for constant volume flow rates and do not require an auxiliary power supply. A special control mechanism guarantees control accuracy over the entire volume flow range. For each model size, the volume flow range is at least 5 times the minimum flow rate. Within this control range, specified at Vmin and Vmax , the set point for the required volume flow rate is adjustable. The volume flow rate is maintained constant at varying pressures within the specified pressure range, with an approximate deviation of between ±5% and ±10% with greater deviations at lower flow rates, especially on the smaller sizes.