Dirtmag on Chilled/Condenser Water

RyanD

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_rod

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.

RyanD

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_rod

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.

RyanD

Sorry for the late response but yes i was looking to install in series with the (sidestream) bag filter/feeder.

hot_rod

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

TCTonkins

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-Ed

@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

RyanD

It is a chemical feeder but also has a 1 micron filter bag (and the magnets I added) inside so it does some filtering.