why is my water yellow

[steff503]

I have a direct, single coil tank with back up electric. The water comes out yellow. Is there any one thing that could cause this? We have flushed the tank but after it heats the water is yellow.
I have an other water heater, propane, same water supply it is not yellow. Although before we got this system the water from the propane heater was yellow.
I had the water dpt out they did not know what could cause it.
Any ideas would be appreciated.

Steff

[Sunking]

Brown, orange, red, or yellow is most likely rust. If it is a gas or electric water heater means time to change it out now as the lining has failed and a leak soon to follow.

[steff503]

This is a new solar water heater. I hope it has not rusted already. Is there a way to test if it is rust?

[LucMan]

What type of tank is it? What is your water system pressure?

[steff503]

LucMan, We are neighbors, I am in Sullivan county NY
It is this tank

http://www.solar-water-heater-pro.com/solar-hot-water-tank-40-gallon.aspx

water system pressure in tank is about 48psi

[LucMan]

Your tank seems to be stainless steel, but still has a magnesium anode rod. Perplexing. I suggest you pull the anode rod and take a look at it to see if there is any magnesium left on it. The anode rods have a steel center core that maybe exposed,rusting and giving you the yellow water. If this is the case replace the anode rod with a new magnesium not aluminum anode rod. Yes the magnesium rods cost twice as much but will be more effective at protecting your tank and they are available as sausage link type so that they can be re-installed in low ceiling height applications.

[steff503]

Hey thanks,
We pulled the rod. It was very pitted, not at all smooth. There is also grit in the bottom of the tank. I removed the rod and plugged the opening and refilled. Got really good and hot today and still no yellow!!
Good call.

[steff503]

Well it's back!!
Once again yellow water. I got a water test kit, tested for Ph, Chlorine,Hardness, Iron, Copper, Nitrites and Nitrates, all results good.
So any other ideas?

[Sunking]

So any other ideas?

Time for professional help. Start with a Lab Test which is inexpensive.

[Robert1234]

Echo to the "get professional help". Sounds like this could be bacterial. Google terms like Crenothrix, Leptothrix, and Gallionella.

[russ]

Well it's back!!
Once again yellow water. I got a water test kit, tested for Ph, Chlorine,Hardness, Iron, Copper, Nitrites and Nitrates, all results good.
So any other ideas?

Many places the state or county do it free or low cost.

[steff503]

OK, After the replies on here and some further research I think I have some rust loving bacteria going on.
My question is If this is what was happening in the old tank, How did it get into my new tank. I did for a while preheat my water with the panels on the roof and send it to the old tank. Now that we finished installing the new tank and put the polyglycol in the panels how can anything get from old tank to new? even if we went from new tank to old then to the sink for a while could it have backed up with the pressure?
Is this in my water source? We have a very large summer population here and the town opens additional well for summer.
Is it possible what ever this is, is in those wells?

[Robert1234]

Or in your pipes. Great quote you can take to the bank... "Life will always find a way." Bacteria love to form biofilms. I'm sure others in your area have experienced the same before. As Sunking said, talk to you local health department. They probably can help lead you to a solution.

[inetdog]

I have a direct, single coil tank with back up electric. The water comes out yellow. Is there any one thing that could cause this? We have flushed the tank but after it heats the water is yellow.
I have an other water heater, propane, same water supply it is not yellow. Although before we got this system the water from the propane heater was yellow.
I had the water dpt out they did not know what could cause it.
Any ideas would be appreciated.

Steff

If I understand this correctly, you now have two heaters in parallel (series?) and the water coming out of the existing propane heater is not yellow any more but the water from the solar tank is?
That hints strongly at some sort of electrically-based chemical phenomenon in play, but does not rule out a bacterial problem. If you just turn off the heat to the new tank does the water from the old heater start to turn yellow? Does turning off the heat to the solar tank (shut off valve in piping or cover the solar thermal panels) cause that water to go back to clear?
Any noticeable change in the taste of the water?

[steff503]

The strangest part is we have 5 apartments on the property. All 5 are before us in the water line. None of those apt. have yellow water. So it can not be water source, although all those have electric water heaters, we have always had propane and now solar. Ours gets much hotter than theirs, much hotter. I would have thought that 185 degree water would have killed any bacteria.

We have them separated, they were in series.

I am waiting till summer ends. We have a very large influx of summer guests in our town. The population goes from about 20,000 to about 60,000 during July and August. I wonder if the town opens a new well. if it goes away when everyone leaves I will know for sure.