Water Turning Blue

[Berdo]

We made our own solar water heating system consisting of 2 4X8 solar panels, with water circulating via a DC pump into our 600 gallon cedar tub. The set up works great. However, we've noticed the copper content is very high, and that the water and sides of the tub have turned a slight blue hue. We were warned that using an open-loop system such as ours might subject the water to high amounts of copper, and discoloration.

We would appreciate any suggestions for how to either remove copper from water, or prevent it from transerring into the water while it is circulating through the copper solar panels.

Thank you,

Berdo

[Cavalier]

check this out"+++++

What is occurring in your plumbing system is refer to as "Blue Water Syndrome". It is not an electrolysis problem but a water chemistry issue. All new copper piping dissolves at a rate of .001-.003 per inch, per year during the first few years of installation. Blue water occurs many times in homes which are larger and only a few occupants or if a soft water conditioner was installed before the piping was in ever used and is over softening the water. There are a few other reasons why you can have an accelerated rate of copper dissolving as well. Some of which is if the pH is below 6.5 copper solvency occurs. In addition the changes made as part of the EPA Safe Water Act of 1991 removing of NOM's from the water has caused a lack of the protective patina which occurs as the copper is dissolving."

We made our own solar water heating system consisting of 2 4X8 solar panels, with water circulating via a DC pump into our 600 gallon cedar tub. The set up works great. However, we've noticed the copper content is very high, and that the water and sides of the tub have turned a slight blue hue. We were warned that using an open-loop system such as ours might subject the water to high amounts of copper, and discoloration.

We would appreciate any suggestions for how to either remove copper from water, or prevent it from transerring into the water while it is circulating through the copper solar panels.

Thank you,

Berdo

[Berdo]

check this out"+++++

What is occurring in your plumbing system is refer to as "Blue Water Syndrome". It is not an electrolysis problem but a water chemistry issue. All new copper piping dissolves at a rate of .001-.003 per inch, per year during the first few years of installation. Blue water occurs many times in homes which are larger and only a few occupants or if a soft water conditioner was installed before the piping was in ever used and is over softening the water. There are a few other reasons why you can have an accelerated rate of copper dissolving as well. Some of which is if the pH is below 6.5 copper solvency occurs. In addition the changes made as part of the EPA Safe Water Act of 1991 removing of NOM's from the water has caused a lack of the protective patina which occurs as the copper is dissolving."

Cavalier:

Thank you for the quick reply. Maybe I should've stated the solar panels were bought used, although the approx. 40' of 1/2" plumbing is new copper. pH is indeed low, although we were cautioned to use as few chemicals as possible in a cedar tub. We will increase pH and see if that helps.

Meantime, can you suggest other cures or - more importantly - preventative measures?

Thank you,

Berdo

[CT-Mike]

Meantime, can you suggest other cures or - more importantly - preventative measures?

Thank you,

Berdo

Probably the easiest method is to add another circ pump and a water-to-water heat exchanger. That way the two fluids do not come into contact with each other and would cure your contamination issue.

[Dr. Spa]

It's not that complicated, the low pH of your water is causing the copper to corrode away, and then any oxidizer you're adding to the water (chlorine, bromine or MPS) is oxidizing the dissolved copper in the water and turning it blue.