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Pex Tubing Discoloration

hr Member Posts: 6,106
as it passes through the various ferrous components. It's pretty hard to keep it crystal clear. A bit grey, but probably not black.

I'm of the opinion that all new systems should be cleaned with a hydronic cleaner first. It rids the system of all sorts of nasties.

At the very least heat the system up and flush it once. This will at least get construction debris and water soluable fluxes out of the piping. Also the manufacturing oils in the boiler.

Then test the water you will fill with for hardness, TDS, and ph. At least. If it's a new well it could have silt. Fill a glass and let it sit overnight to see.

Also check for smell. Iron water could coat the heat exchange surfaces.

A good hydronic treatment is also a good idea, in my opinion. Especially in expensive multi metal mod con boiler systems.

Would you put used or dirty motor oil in your new truck? :)

hot rod

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  • Tom Eigo
    Tom Eigo Member Posts: 8

    We're building a new home and have a quite involved radiant floor heating system utilizing Wirsbo Aluminum plates in the joist space. My question is I notice the the pex tubing looks discolored as if the water in it is almost black. Is this normal or should I be concerned. Let me know if you need any additional info. Thanks
  • Jeff Lawrence_25
    Jeff Lawrence_25 Member Posts: 746
    I've seen that before

    My biggest questions to you are 1) What's your water temprature and 2)are you on well water?
  • kevin coppinger_4
    kevin coppinger_4 Member Posts: 2,124
    no great...

    concern. If it is a cast iron boiler and the water in the system has not been cleaned out it is bound to happen. Many guys don't clean the system when it is put into service...Rhomar products will help...kpc

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  • Tom Eigo
    Tom Eigo Member Posts: 8

    It's a new system consisting of two veissmen wall hung condensing boilers. I noticed before the system was calibrated they were running zone of temperatures of 150-160 degreesfor a few weeks. I question it because I thought it should be around 85-100 degrees and the fuel consumption was real high. It is on a well system which is fairly new. The system has 16 zones all together, five of which are to hydroair units. The technician said it may be residual flux from soldering, but doesn't seem likely to me. Thanks
  • kevin coppinger_4
    kevin coppinger_4 Member Posts: 2,124
    what brand ...

    of PEX and what hePEX or Aquapex.....kpc

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  • Tom Eigo
    Tom Eigo Member Posts: 8

    Wirsbo hepex
  • S Ebels
    S Ebels Member Posts: 2,322
    Couple things

    #1. You stated that this was well water and the well was new. Do you know if the well was run for a good day or so, with the water being dumped, before it was connected to the house system? Reason being, new wells are always sanitized before being put into service. Clorine is the sanitizing agent most often used for this and it will react sometimes depending on what minerals are in your water. Any taste or odor of clorine in your tap water?

    #2. If residual flux is a question mark, the system should be purged and checked for correct PH. It needs to be corrected if it's off target.
  • Weezbo
    Weezbo Member Posts: 6,232
    it is better late than never...

    flushing the system is certainly in order however the stuff might be carbon from soldering and brazing .Tom,the thing that i would like to note on your thread is that i have noticed over the years that the higher temp waters /fluids often seem to be "darker" coloured within the pex. it doesnt really concern me although it is something that i have noticed.
  • Tom Eigo
    Tom Eigo Member Posts: 8

    Thanks to all for the help.
  • Jerry_15
    Jerry_15 Member Posts: 379

    Yeah, I hate to ask this too, but what kind of boiler, and does the pex have an oxygen barrier.
This discussion has been closed.