Click here to Find a Contractor in your area.
In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Need to contact us? Visit https://heatinghelp.com/contact-us/.

Brown DrainBack Water

Solar Wizards,



My System:

4 SunEarth  4' x 10' collectors

Stainless Plate Heat Exchanger (radiant); Quad Rod Heat Exchanger (DHW)

15-20 Gallon Drain-back Tank

Unpressurized Drain-back Setup

Closed Loop



A few months after firing up my system about 2-3 years ago, I began noticing just a slight browning of the water visible through the sight glass outside my drain-back tank.  It presently looks like what's shown in the attached photo.



I'm interested in hearing your thoughts on how to proceed and how much of a concern this "browning" is.





Thanks,



Martin Romero

Comments

  • hot rodhot rod Posts: 6,717
    my guess

    would be that the system has a pump with a cast iron body. If so that is where the red color is coming from. A bit of color actually makes it easier to see the level in the sight glass.



    I prefer a pressurized drainback, but as long as it is a true closed loop, you should not see a lot more dis-color.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • Browning water

    Thanks Hot Rod,



    I was certain the pump was brass, but I will double check. No real concern about heat transfer?
  • Kevin_in_DenverKevin_in_Denver Posts: 588
    edited November 2012
    Most likely a steel tank

    Martin,



    My first guess was also a cast iron pump. That tank could be steel, however. Do you have the brand name and model for it? Even if it is a glass-lined steel tank, a little bit of rusting at the fittings would be normal.



    BTW if it is a true unpressurized drainback system, that means it must be vented somewhere. A vented system usually causes a cast iron pump to fail prematurely. If it's truly a closed loop system, it will create some pressure when the air and water gets hot.
    Superinsulated Passive solar house, Buderus in floor backup heat by Mark Eatherton, 3KW grid-tied PV system, various solar thermal experiments
This discussion has been closed.

Welcome

It looks like you're new here. If you want to get involved, click one of these buttons!