This thread has been bookmarked. Visit your bookmarked threads to review.
Post a Reply to this Thread
Brown DrainBack Water (4 Posts)
Brown DrainBack WaterSolar Wizards,
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
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.
Martin RomeroThis post was edited by an admin on November 6, 2012 11:11 PM.
my guesswould 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.
Browning waterThanks Hot Rod,
I was certain the pump was brass, but I will double check. No real concern about heat transfer?
Most likely a steel tankMartin,
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 experimentsThis post was edited by an admin on November 9, 2012 2:22 PM.