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WRM / WRMD Constant Volume Controllers

    • Product Details


      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.

      Product Description

      • WRMVolume flow rate controllers are mechanical controllers that provide a constant volume flow rate in ventilation and air conditioning installations.
      • WRM/MVolume flow rate controller with actuator-driven adjustment of the volume flow rate set point.
      • WRMDVolume flow rate controller with acoustic insulation for the reduction of external sound radiation.


      • Volume flow range:
        45 to 5200 m³/h
      • Pressure range: 50 to 1000 Pa
      • Leak tightness classification: B in accordance with EN 1751
      • Internal temperature range:-20 to +70°C, 90°C for a short time only
      • Lip seals on both connection ends

      Accessories (Transformer)

      • WT24.240240v to 24v AC Power supply


      • Actuator AC 230V or AC/DC 24V, setting to two volume low set points
      • Continuous actuator AC/DC 24V, setting to any desired volume low set point
      • External acoustic insulation with sheet metal jacket

      Product Specification

      Related links

      WRM Constant Volume Controllers Installation Guide

      Waterloo Mill Finish


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