Is it possible for minerals in drinking water to solidify when high temperatures are applied? The minerals in mind are: iron, copper, aluminum, magnesium.
Background: I have small, brittle, darkish flakes appearing in my hot water system. The manufacturer of my tankless hot water heater said it's possible for these elements to solidify in this manner over time.
Looking at their website, I found this brief explanation: http://support.noritz.com/article/faq-what-is-water-hardness-46.html
"Water hardness is the measure of dissolved calcium, magnesium, and other minerals in your drinking water. It is typically measured in grains of hardness which equates to 17.1 mg/L of dissolved calcium carbonate. If not treated hard water can cause mineral build-up in your heater. Mineral build-up reduces flow and produces flakes at your fixtures."
We got out water hardness measured, and it came back as 68 mg/L.
The temperature of the water heater is set to 130F. I believe that the heater has a higher internal temperature.
I'm not sure why they are dark/black in color, all the pictures I'm seeing for calcium carbonate are white.