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General => General Chat => Topic started by: cyclin_al on March 24, 2020, 06:28:57 am

Title: Residential water issues
Post by: cyclin_al on March 24, 2020, 06:28:57 am
Please bear with me since the topic is water but there is an electrical aspect to it.
Moderators:  I think this is a 'general' topic, but please move if there is a more suitable category for this.

I would like to ask a question about water.  I know some here on this forum have knowledge that goes well beyond electrical and electronics, but possibly electrical knowledge comes into play as well.
My residential water supply is described as "very aggressive" and I am looking for what I can do about it I foresee the home plumbing work getting expensive.
You can see some worrisome symptoms in the 4 photos attached (fixtures rusting, fixtures eroding, development of tiny leaks and mineral deposits).
[attach=1]  [attach=2]  [attach=3]  [attach=4]
What are your thoughts about investigating further if there is any issue with the following:

What I know about the situation is demonstrated in the attached photos.
The water is known to have total dissolved solids of 48 grains (not the correct unit of measure, but the slang used by plumbers) which is mostly Calcium and some Sodium.
pH is 7.2, which is pretty good.
We see no issues with water hardness when soap is used; there is a water softener.

The water supply is from a well at 350 feet deep (Canada is in reality only quasi-metric still).
The well pump is submerged and runs on North-American 240 VAC, 3/4 horsepower.
The supply line to the house is plastic to the pressure tank (now replaced with fiberglass tank).
From there, tubing is PEX until noted otherwise.
This leads to a screen filter to take out sand.  A small amount of sand builds up over time, but the filter has taken on a red tint.
Next is a large capacity water softener, which is working well according to water tests by the installer. 
Last treatment is a 5 micron carbon block filter.  (water may smell a bit of sulfur and pressure drops when this filter is due to be replaced)
The water then feeds to the hot water heater tank.
From here onward, the tubing is all copper pipe throughout the house.
There is a grounding cable clamped to the cold water copper pipe immediately after the supply to the hot water tank.

I have read a couple of books about water and they do not offer any clues.
My chemistry is long-forgotten so have not looked into any serious books on this aspect.
Any thoughts or practical advice of what I should look into?
Title: Re: Residential water issues
Post by: shakalnokturn on March 27, 2020, 08:18:17 am
Sorry for not giving any answers...

Considering your photos are of the outside of the plumbing, does it actually leak?
What's the air quality lie where you live? Any chance it could be caused mainly from condensation on the outer-side of the brass links?
Title: Re: Residential water issues
Post by: jogri on March 27, 2020, 11:26:49 am
That blue stuff is copper(II)sulfate, looks like you have quite a lot of it. The white stuff could be calcium sulfate as it has a rather poor solubility (the moisture would have deterioated salts with a high solubility in water). It is normal for water to have a rather high amount of dissolved sulfates, but it shouldn't attack copper pipes like that. The red tint on your sand filter could be some form of rust.

You mentioned that it "smelled like sulfur" when your filter needs replacement? Do you mean a smell of rotten eggs? That's not sulfur, that comes from trace amounts of dissolved H2S.

Sorry that i can't offer you any concrete ideas how to fix this problem, but you should definitely get your water checked for high concentrations of ions (sulfate, CO2-, etc). And where was the pH measured? If it was measured at the well you should also measure the pH of the water that comes out of your tap.
Title: Re: Residential water issues
Post by: Red Squirrel on March 27, 2020, 02:47:41 pm
That's a really oddball issue.  I would try to clean it all up just to see if it starts doing it again.  Maybe buy a piece of copper pipe and let it sit just to see if it happens to a piece of pipe that is not actually part of the plumbing system.   It could at least rule out an environmental issue like temp/humidity or some kind of gas in the air causing it.

Wonder if some kind of electrical issue could cause this, like current leaking through the pipes.  Put a clamp meter around the pipe to see if it's passing current.   Not sure if that would actually cause that problem though.
Title: Re: Residential water issues
Post by: SeanB on March 27, 2020, 04:53:41 pm
If your well water is sour ( the sulphur) then you really have no option but to remove it, as it will corrode the piping from the inside out, leaking to pinhole leaks. Only way to do it cheaply is to buy a large ion exchange column, and run your drinking water through it, and run this to your taps for drinkable water, like the kitchen and basin taps. The other water probably best to simply replace the copper piping with PEX, and for the hot water check the sacrificial anode in the water heater, which will be wearing away fast, probably gone in 6 months.

All pipes replace with PEX, and for the input side have some cascaded cartridge filters before your pressure bladder, probably at least 3 stages, finishing off with a 0.3 micron one. For both water feeds a charcoal filter as well, to remove the odours, and non return valves where it splits to the 2 separate feed systems. water softener for the washing feed, sounds like you need to get a lot of carbonates out, but it is not getting the sulphates out, which is causing the corrosion.

Grounding will have to be separate to ground rods, the more the merrier, installed correctly.

At a first check magnesium anodes, likely they are gone in the water heater.
Title: Re: Residential water issues
Post by: Red Squirrel on March 27, 2020, 07:41:19 pm
Whole house reverse osmosis or water softner might be a good idea too.  Well water can be bad on everything in general so may as well filter it right at the point of entry.  I guess there is an ongoing cost to that though.  Filters and other consumables.
Title: Re: Residential water issues
Post by: Theboel on March 27, 2020, 08:00:44 pm
Most of well water contain CO2 and Sulfur, the easiest way to taken it away is "air stripping" mean You need to contact the water as much as possible to air.
You can use water tower to fall the water from height to made water contact to air or if it not possible You can introduce air use compressor to generated air bubble in a water tank. (try to find nano bubble in google).
then I suggest You to put at least 2 additional filter, carbon active filter and greensand filter
if this two step not satisfying then I consider AOP (advanced oxidation process)

Title: Re: Residential water issues
Post by: Bud on March 27, 2020, 08:34:28 pm
I second SeanB, check the waterheater as part of troubleshooting. Was the waterheater ever drained? Drain it to check if water is clean at the bottom of the tank.
Title: Re: Residential water issues
Post by: cyclin_al on April 02, 2020, 04:39:29 am
Thanks for all the replies!  You have been insightful enough to ask about what I forgot to consider to provide and also some good possibilities.

The plumbing does not leak at the moment.  I will come back to that with the hot water heater.

The environment around the hot water heater tank is extremely dry in winter (up to 35% relative humidity when drying out ski clothing; not great to put in an electronics lab) to quite damp in the summer (up to 80% RH).  The well water is quite cold due to the well depth, so condensation is an issue in summer.  There is a length of 1 inch copper pipe stored in the same room and remains at ambient temperature which appears in excellent shape.  That would likely rule out gas in the air.  Under the kitchen sink is upstairs and should get a reasonable amount of ventilation and stable temperature/humidity.  However, under the sink comes along with storage of plenty of cleaning chemicals.

Would calcium sulfate be an indication that the water softener may not be operating properly?  My understanding was that should replace all calcium with sodium.  Testing for ions sounds like something worthy to follow up on.  Does that testing differentiate between different types of ions, since I assume there will be high levels of sodium ions?  That could lead to the suggestion of the ion exchange column.
pH was measured at a tap, so would be the same water as in the house supply part of the system.

@Red Squirrel, since you are also in Canada, can you recommend a suitable clamp meter or specs?  I would assume any currents would be relatively small and a cheap meter would not be helpful.  I can always use more TE, so long as someone else does not consider it blowing the budget.
It sounds like investigating where that grounding cable goes could be useful as well.

Currently, the cascaded filters are 2 stages including charcoal down to 5 micron.  What would be the benefit of 0.3 micron?  My understanding is this size was to filter out bacteria and larger viruses.  The filters are after the pressure bladder, rather than the suggestion to put them before.  I was recommended to have the final stage after the water softener.

Any changes to the piping that I am doing as I go use PEX.  That results in fewer joints.  However, the joints in PEX are still an issue, as seen in the supply to the hot water tank.  I have some nylon fittings to try out to see if that is any better than the brass fittings to connect PEX.

Whole house reverse osmosis is not going to be economically viable.  I calculated that buying the large bottles of drinking water would still be less expensive than a reverse osmosis system for only drinking water over at least a 50 year period.

The hot water heater was replaced 5 years ago.  The old hot water output nipple had corroded off, causing hot water to spew all over.  I caught it quickly  :phew: and had the tank replaced.  The new tank started to have a small leak in the pressure relief valve after 4 years and I replaced the valve.  Replacing that valve was just enough to crack the hot water output nipple as it was heavily corroded similar to the old tank, but this time was able to re-tap the thread.  Oops, it is not shown in the photo, but the hot water output looks okay after a year now.
The new tank has been flushed but not fully drained from the drain faucet yearly; only a bit of red material was noted initially and then the water would run clear; probably the same rust as suggested elsewhere in the system.
One interesting thing to note is that I also flushed from the pressure relief valve at the top of the tank also.  I observed a small amount of gas would release before a bit of red-colored water and after the water would run clear.
The sacrificial anode is something I have forgotten completely about.  It has never been checked or replaced.    How long is the anode when new?  I have limited clearance and may not be able to easily remove or install it.  I understood the anode protected the tank, but I get the sense from your responses that it may be meant to protect the whole system?
Note to myself: any future work should consider at least a somewhat easy way to disconnect the tank and tip over for access to the anode if needed.

Now I have some leads to follow up on...
Title: Re: Residential water issues
Post by: SeanB on April 02, 2020, 10:15:21 am
With your PEX pipe you get stainless steel ferrules you put inside the plastic by the fittings, to reinforce the wall there.  Cascaded filters is so that you gradually remove sediments, and the 0.3 micron filters get most of the turbidity out of the water, sop it does not deposit in the pipes, which can also create concentration gradients in the bottom, making for corrosion cells.

Carbonate deposits mean your softener needs either service or salt.  the anode is almost the length of the tank, but most are segmented so they can be bent in sections, and are the diameter of the bolt, around 3/4in.  If your tank inlet corroded the anode is very likely gone long ago, they corrode fast with water softeners, as the water contains so much more ions to drive the reactions that corrode them preferentially.  6 months would probably be the anode life, and they are easy to get, though your tank might break if you try to remove it now as the wall will be weak.  New tank remove it and put back with some anti corrosion sealer, so you can undo it regularly to replace it, as the factory typically puts them in with a permanent sealer to prevent leaks.

When getting the new tank go for the plastic one, which cannot be as hot, but at least has the benefit of not corroding out, otherwise go for a glass lined one, though they are not going to last long with the pressure swings in a pumped system, as this cracks the glass fired to the wall, and the underlying steel corrodes fast. Best for this is a non pressurised gravity feed copper tanked system, but has to be high up, does not drive showers well, and has poor flow on hot taps.
Title: Re: Residential water issues
Post by: jogri on April 02, 2020, 10:19:47 am
Would calcium sulfate be an indication that the water softener may not be operating properly?  My understanding was that should replace all calcium with sodium.

Yup, that's correct. It basically captures calcium and magnesium ions and replaces them with sodium, but you have to keep adding sodium ions in order to keep it working. Maybe you didn't add enough? Another option would be that the ion exchanger has stopped working properly because it is gummed up with other contaminants, so you could also consider changing that part.

Testing for ions sounds like something worthy to follow up on.  Does that testing differentiate between different types of ions, since I assume there will be high levels of sodium ions?

You can actually do this yourself, just heat a drop of water in the (blue) flame of a gas burner and watch the colour of the flame (you should do this in the dark). It should be yellow, if it has a tint of red your water softener isn't working properly and you still have calcium ions in your water. Wiki has an article about it, but the pictures of the flame colours kinda suck: ( Sure, this doesn't replace a (properly rather inexpensive) lab test but it's a good starting point.