Identify the cause of this corrosion

[H20issues]

Hi All,
new to the blog but I hope someone can help out. Looking at buying a house 12 years old. everything looks great until I get to the basement.... most of the joints carrying water have significant corrosion - much more than they should. the house has well water. I would hate to make an offer on the house and find out 1) the water has a serious contamination issue, 2)it will require significant money to put in a purification system and 3) most likely all the piping will need to be taken out.
I would rather use that as part of the negotiation up front rather than after an offer is made.
Any thoughts of what the corrosion may be? photos attached.

 

[Reach4]

I don't see most joints having corrosion or deposits. I see some valves having deposits of some sort where there are small leaks.

I am not a pro, but I suspect the water is going to need some more work. Is the pH low and that is corrosion? I would expect blue-green for corrosion giving the copper/brass. I do see a little green, but not much That blue tank may be a pH raising tank. Is there a fill port for calcite in the side near the top of the tank? Is the water very hard and the small leaks are calcium carbonate deposits? That vacuum breaker above the gray tank could be leaking... I don't know.

What is that gray tank, anyway? It seems small for a well pressure tank, and usually you don't have a separate thermal expansion tank with a well system.

While you are at it, I would post a picture of the pump-related area.

Ask to see the lab test for the raw water. They or their water treatment people should have that. If you want your own test, I like kit90 from http://www.karlabs.com/watertestkit/ Expect it to take ~2 weeks from when you order via the web until your get the results by email, presuming you return the filled sample kit quickly. That time includes two trips in the mail. There are services that can do it faster for more money, and there are places that can do it slower for more money.

Having your own pump, treatment and septic can take some work and expense. But city sewer and water can be a considerable recurring expense too.

If you identified where you are in CT, somebody might have experience in what typical water is like there.

 

[Sponsor]

 

[H20issues]

I don't see most joints having corrosion or deposits. I see some valves having deposits of some sort where there are small leaks.

I am not a pro, but I suspect the water is going to need some more work. Is the pH low and that is corrosion? I would expect blue-green for corrosion giving the copper/brass. I do see a little green, but not much That blue tank may be a pH raising tank. Is there a fill port for calcite in the side near the top of the tank? Is the water very hard and the small leaks are calcium carbonate deposits? That vacuum breaker above the gray tank could be leaking... I don't know.

What is that gray tank, anyway? It seems small for a well pressure tank, and usually you don't have a separate thermal expansion tank with a well system.

While you are at it, I would post a picture of the pump-related area.

Ask to see the lab test for the raw water. They or their water treatment people should have that. If you want your own test, I like kit90 from http://www.karlabs.com/watertestkit/ Expect it to take ~2 weeks from when you order via the web until your get the results by email, presuming you return the filled sample kit quickly. That time includes two trips in the mail. There are services that can do it faster for more money, and there are places that can do it slower for more money.

Having your own pump, treatment and septic can take some work and expense. But city sewer and water can be a considerable recurring expense too.

If you identified where you are in CT, somebody might have experience in what typical water is like there.

thanks Reach 4,
you are right, there is little, if any, blue/green corrosion so do I do not think it is low pH.
the blue tank is part of the well.
the grey tank is part of the furnace. parts corroded at that point are cast iron.
good idea regarding the water treatment/lab test. I will ask if the homeowner has that information and if not request a water sample.

 

[Reach4]

the grey tank is part of the furnace. parts corroded at that point are cast iron.

Ahh. That makes sense. Hydronic heat is usually nicer than hot air. It is good in itself, and it is often in a house that has other premium characteristics.

Kit 90 has the tests you might want for water treatment. The ones that test much more would be to check for contamination from fairly uncommon chemicals.

 

[Jadnashua]

It looks like mineral deposits caused by a slow leak. Try scraping some of it off, then place it in a glass with some plain white vinegar...let it sit for 24-hours. If it dissolves, it's almost certainly calcium based mineral deposits.

While annoying, not particularly critical, but the joints should be redone to make them water tight. It is a sign that the water is hard, which would show up in a water test. If they have a softener, you may want a water sample after the softener, too, to test how well it is functioning. For that, a simple hardness test is all that is needed verses a more complete water quality from the well outlet itself.

 

[Kreemoweet]

Although you clearly have some chronic leaks there that don't help matters, the main problem may be the corroding
fittings themselves. It's not at all uncommon to get Chinese-made "brass" valves and fittings that start corroding
instantly, and heavily, on being wetted. With white corrosion products, not the typical blue/green stuff. Gosh knows
what they put in that metal . . .

 

[Dj2]

I agree, if you had really bad water, then most of the connections would have corrosion, not just select few.

Replace the corroded valves with USA made real brass parts, AFTER you negotiated a lower price on the house.

 

[H20issues]

I agree, if you had really bad water, then most of the connections would have corrosion, not just select few.

Replace the corroded valves with USA made real brass parts, AFTER you negotiated a lower price on the house.

Thanks KoW and dj2. good advice!

 

[Craigpump]

If you're buying, I'm sure you will have a general home inspection done along with a septic and you should also have a well & pump specialist come in. Have the inspector take samples and have the water tested for chemical, bacteria & radon. Depending on the location, you may want to test for uranium & arsenic also.

I say this all the time, forget mail order labs. Bacteria needs to be set immediately & pH tested promptly for the most accurate results. Find a local lab that is state certified, here in CT you can call Aqua Environmental in Newtown or Phoenix Environmental in Manchester, there are others, but I've had good luck with these two.

 

[Jadnashua]

Until you clean it off, mineral deposits caused by a leak can look like corrosion. If it dissolves in acid (the vinegar I suggested is the most readily available and safe), it's likely mineral deposits from leaking. Depending on the quality of the workmanship, not all joints would leak. And, depending on the quality of the fittings, not all of them may corrode.