Sidestream Filtration Units
Cobra Cyclone Unit
Label on Cobra Cyclone Unit
steel closed recovery filter housing
Sidestream Filtration Unit

CSF-CRS Sidestream Filtration Units

Regular price £7,665.00 £0.00 Unit price per

SOCOTEC’s CSF series of cyclone filtration units are designed for sidestream filtration of closed water systems for the removal of suspended solids and sludge. A sidestream flow of water is drawn from the system by the circulation pump built into the CSF unit and pumped though the cyclone where suspended solids are removed by centrifugal force. The cleaned water is returned to the system and the dirt and debris retained in our bag filter housing. The system offers a zero water loss solution for continuous filtration of closed water systems removing dirt, debris and suspended solids.

By using the Cobra Cyclone Separator, you will:

  • Maintain system cleanliness
  • Optimise your chemical treatment programme
  • Lower chemical costs by reducing potential bacteriological food sources
  • Remove sludge, debris and corrosive matter, which would otherwise build up and lead to higher energy consumption and poor circulation
  • Protect and extend the life of your systems
  • Eliminate purged water losses, with no requirement to make-up the system
  • Avoid diluting chemical reserves in the system’s circuit, including Glycol.

      The Cobra Cyclone Separator is designed using a multicolour text display, which features an emergency stop/isolator switch and alarm. Pipework is carbon steel with an external galvanised finish for high tensile strength, creating a long life-expectancy and low maintenance needs to reduce your long-term costs.

      A recirculating pump with a stainless steel impeller is used to maintain flow through the hydro cylone to ensure efficient dirt separation. The stainless steel closed recovery filter housing offers high corrosion resistance, durability and reliability.

      Optional alarms include a flow sensor which indicates that the filter bag is full, as well as flow/no flow, the latter of which can be connected to your Building Management Systems (BMS) interface for remote monitoring and control.

      How Cobra Cyclone Separator Works
      1. Driven by the inlet pressure, liquids and solids enter the top chamber at a tangent, causing a rotation. They accelerate through the tangential slots/holes in the top section of the separator and down into the centre section, causing rapid rotation.
      2. The rotation of the liquid forms a vortex within the unit. The centrifugal action forces the separation of heavy particles from the water.
      3. The deflector plate halts the rotating movement and clean water flows through the central vortex from the top of the cyclone.
      4. Clean water exits through the outlet at the top.
      5. The separated particles accumulate in the bottom collection chamber, where they are dispelled into the solids collector.

      Watch the video below for a demonstration of the Cobra Cyclone inner workings. 

        Please find below the basic technical information on each of the sidestream filtration units. Further information can be found here to help you select the correct unit based on your system volume.

        Model Ref.

        Min. Connection Size

        Filtration Flow Rate (m3/hr)

        To Suit System Volume (m3)



        1 – 2.5

        3 – 8



        2.5 – 4.5

        5 – 10



        4.5 – 7.5

        8 – 20



        10 – 16

        20 – 60



        14.5 – 24

        30 – 90



        21.5 – 35

        45 – 130



        30 – 60

        60 – 240

        CS40/3PH/CRS/10-G 4" 66 - 90 90 - 360

        Some of the key benefits of the Cobra Cyclone Separator include:

        • Progressive filtration down to five micron
        • No media to change
        • No need to back wash or flush the filter
        • No reduction in flow
        • Constant minimal pressure drop
        • Only one Cobra hydro-cyclone required
        • No complex valving arrangement
        • No risk of causing system pressure or water loss
        • No media or dead legs for bacteria to thrive
        • Minimal servicing requirements
        • No circuit water loss with the addition of the Closed Recovery System (CRS).

        Our standard UK shipping time is 2-3 weeks and costs £85 (including pallet cost). Should you need express delivery or delivery outside the UK, please contact us

        For further information on Cobra Cyclone Separators, take a look at our FAQS.

        SOCOTEC’s Cobra Sidestream Filtration Units are available for hire and purchase. If you wish to receive additional advice on how to treat your water systems, please contact us.