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Dirtmag on Chilled/Condenser Water

RyanDRyanD Posts: 8Member
Hi everyone, longtime reader first time question ask er. Is anyone here using magnet separators on chilled or closed loop condenser water to deal with high iron levels?


  • hot_rodhot_rod Posts: 11,468Member
    Look at installing a magnetic separator device. The mesh media in the unit will pull down to a 5 micron particle, the magnet will attract the smaller magnetite (black) and hematite (red colored) particles down to a .05 size!

    If a system has had high iron content fluid running in it you may need to add some cleaners and scrub out all the build up. Even a small layer of red oxide on heat exchange surfaces will take a toll on efficiency and performance of the chillers and heat emitters.

    If you use a cleaner and flush the system, use filtered RO or demineralized water to refill the system.

    Also add some conditioner with the filtered fill water to keep the system protected.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • RyanDRyanD Posts: 8Member
    Thanks Bob,
    I am hoping to get the OK to install a small 3/4" separator on the inlet side of the bag filter/chemical feeder. I currently have some small magnets inside of a 1 micron bag which has been working ( down by 4 ppm in one month) but i am hoping to find a more permanent set up.

    Pictures attached of what the magnets pick up after a few days.

    A flush and fill cant be done to easily is in an 18 story building, 14" risers with both base building and tenant equipment.
  • hot_rodhot_rod Posts: 11,468Member
    Installed as a side stream device is what I think you are considering?

    With a DirtMag you can blow down the sediment without opening up the device.

    Any particles flowing in the fluid you will eventually remove.

    The gunk coating the HX surfaces may still cause concerns. Although a chilled system may not precipitate as much as heated water.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • RyanDRyanD Posts: 8Member
    Sorry for the late response but yes i was looking to install in series with the (sidestream) bag filter/feeder.

  • hot_rodhot_rod Posts: 11,468Member
    yes it would help to install one next to the filter

    But whatever device you add will also need to be blown down ocassionally

    Looking at that pipe size, you could be cleaning that system for some time?

    One nice feature of the Caleffi is you do not need to disassemble to clean out, remove the magnet and blow it out
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • TCTonkinsTCTonkins Posts: 1Member
    It is interesting to note that magnetite and scale combine and form a hard coating on pipework and in cast iron heat exchangers. Magnetite is the "glue" for scale. As well as reduction in efficiency, the build of scale & magnetite can cause overheating leading to failure. If you remove the magnetite, scale build up can become less of a problem. Magnetic filtration is becoming much more commonly used in North America for both residential and commercial hydronic heating systems . There are several manufacturers now providing these products and treatment formulas.
  • EBEBRATT-EdEBEBRATT-Ed Posts: 5,804Member
    @RyanD ,
    I don't think what you are looking at in the picture is side stream filter. That is simply a "shot feeder" used to add chemicals. that's why the piping is so small
  • RyanDRyanD Posts: 8Member
    It is a chemical feeder but also has a 1 micron filter bag (and the magnets I added) inside so it does some filtering.
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