water heaters and water softeners

[askolover]

Well, today I was snoozing along in my little bed only to be awakened by hubby's distress call, "Greg, the house is flooding!"  I jump out of bed to find the water heater tank has failed and water is spraying somewhere inside the flue.  I throw on my designer disaster outfit and go out to shut off the water and begin the emergency clean up routine.  Get the tank drained, disconnected and out on the porch.  I tilted it forward to finish draining the remaining inch or so of water from the bottom...it's red rusty water!  No white mineral pieces though.  Granted, it's right at exactly 10 years old and has had only softened water in it since I installed it in '06.  My parents' last WH lasted over 20 and was still fine when they replaced it before a failure occurred....but they don't have a water softener. 

Now my question is, anybody notice a higher failure rate due to corrosion when a water softener is involved?  I mean, it does add sodium to the water.  Just last month I had to replace both shut off valves under the kitchen sink because they both began leaking at the same time and were installed at the same time in  '99.  My pipes are CPVC so they are fine.  I'm thinking the anode went away and then the tank began sacrificing itself.    I've been reading up on powered anodes...anyone have experience with one of them?  They are made of titanium.  Link below.  They are a little expensive but cheaper than $500 for a WH plus possible damage.  I've never had any odors from anode reactions, but I've read that softeners can cause anodes to be consumed more rapidly due to  the corrosive properties of the water.  I should have tried to remove the anode for inspection while it was still full of water to help hold it in place because they can be screwed in there really tight, but alas I was just wanting to get it out of there.  I went ahead and bought another Rheem built one from HD simply because it was the same size and would just slide right in there. It has a 6 year tank warranty.  Wish it were made of stainless steel!  Any thoughts, comments, recommendations to share?

http://www.waterheaterrescue.com/pages/OrderPages/XCart/Power-Anode-Coupling.html

 

[delaneymeegan]

 

1. Yes, the salt can expose metal to rusting.  Try dialing back the salt setting on the softener.  Also, water softeners are not good for our skin, nor good to drink.  You'll also use less salt.

 

2. Unsoftened water carrys minerals.  When those minerals collect on surfaces like the inside of a water heater tank, it acts as a protective coating, thus giving longevity.   Unfortunately, we don't want that same mineral build up in other fixtures, on our clothes, dishes, or skin.

 

3. One should shut down their water heater every couple of years, remove the rod and replace when necessary.  Most people probably don't.

 

4. One should turn on the water faucet at the bottom of the water heater, for several minutes every six months, to drain off sediment that has collected.  Again, most people don't.  When I was a landlord I would routinely do a yearly service to each unit, hose in hand.  I would connect the hose to the faucet, run it to the sewer, and turn it on for about 5 minutes.  It's better than dealing with a hole in the tank..... and I HAVE.

 

In one own home you can get a piece of old hose and connect it to the faucet and routed to a drain and leave it on.  Then just run the faucet every once in a while.

 

I've also replaced, on occasion, that dinky awkward plastic water heater drain faucet that some models have, with an actual steel and brass faucet that will hold up over time and is easier to operate. 

 

[askolover]

I actually did that with the plastic drain valve on the old heater, put on a 3/4" ball valve that wouldn't clog and flushed.  But the failure happened at the top in the flue.  I regularly flush the TPR valve too.  The WH is located right by my washer so it's easy to do.  The salt setting isn't very hi, and only has to regenerate every 12 days.  I'll wait a year before I change out the drain valve in case I need something in the warranty.  I'm seriously researching those powered anode rods.

 

[washer111]

Be wary in dialling back your salt setting is all I have to say. Eventually you'll get to the point where you're using salt, but you still have hard water.
The factory setting gives you about 75% capacity of the resins. To get 100% capacity, salt usage has to be doubled from whatever the factory value is. If you reduce the salt usage, regeneration must occur more often, using more water and more salt in the long run.

If the salt (sodium) is concerning you, Potassium salt exists. Although there are some caveats. It costs more, and you need to use 25% more.
You may also choose to filter drinking water - that said, salt content in the water is directly proportionate to the mineral content (because of ion exchange), so medium-hard water (i.e. 10gpg) will be giving you less salt than hard water (20gpg).

Here in the city where I live now - water is soft.
Yet our water heater is visibly rusting, and is only a few years old. The stories I've heard from others (when we previously lived here) indicate water heaters only lasting 10-15yrs.

This has more to do with the anode rod naturally degrading and failing to protect the tank, one way or another.
That, and tanks are built lighter and aren't made the way they used to be (metallurgy wise) - obviously betting on the fact that people won't change the anode.

Changing your anode, or using one of those new-fangled electronic doo-dads is the solution.

Its like the cheap inkjet printers where ink costs twice that of a new printer, isn't it? Similar principle at play.

 

[delaneymeegan]

 

 

I don't know about Water Softeners in Ausie-land, but here there is no "factory setting" for salt useage.   That's because one sets the useage based on the hardness of the water in ones area.  The factory has no idea.  

 

 

 

[washer111]

The system we had at home is the ubiquitous Fleck 5600 - ubiquitous in the USA, not so sure here in Australia because I think water softening applications are very limited to a few select areas in reasonably remote areas.

On the back is a sticker plastered on that says "Salt Setting 9LBS."
For most home systems, this is the most common setting. However, some people use higher capacity tanks or sometimes smaller capacity tanks.
Fleck sells a different control valve under this model for each, because a larger or smaller tank need the appropriate increase or decrease in water flow (controlled by the Drain Line Flow Control, DLFC) as well as the appropriate venturi to completely empty the brine tank of water each regeneration, then successfully refill it to a particular level.

in order to change your softening capacity, what is changed is the frequency of regeneration corresponding to your water hardness and the grain capacity of your system. A reserve amount of 75 gallons per person in the house, is then subtracted from this capacity to give you the appropriate frequency.
Gallon Capacity = (Grain Capacity * 0.75) / (Water Hardness) - (75 x No. of persons)

For example, we had 25GPG hardness in our previous home.
Capacity = (24000 * 0.75) / 25 - 300
Capacity = 420 US Gallon

For what its worth, 24000 grains is a 3/4 cu. ft. system.

https://www.softenerparts.com/kb_results.asp?ID=16
https://www.softenerparts.com/kb_results.asp?ID=56

The two above links explain more in-depth. The one on the bottom is an explanation of what I did above, with the important message that to achieve the last 25% of capacity (which we actually ignore), the salt usage must be doubled. This is true for all softening units.

 

[washman]

stainless steel WH

never heard of them. Not sure where they are made either.

Highly Efficient electric residential water heater made with durable quality stainless steel

Insulated with heavy duty foam for minimal heat loss and stainless steel incoloy elements this electric residential water heater is highly efficient and promises a longer tank life.

www.htproducts.com

 

[wayupnorth]

My water softener is a Blake 5600 installed last year to replace a failed Rainsoft system. My water is extremely hard with lots of iron. I am all pvc and pex for plumbing but I do see rust spreading ever so slowly on my boiler and water pump. That Blake works fine and I just dump a bag of rust remover salt once a month and I got great well water. Several of my neighbors run lines to the lake in front of us to get that nice water but pay thru the nose all winter for their heat tapes to keep the line from freezing.

 

[sudsmaster]

I've been under the impression that soft water tends to be more corrosive to metals, and is an issue. I've also read that it's better to put the water softener on the cold water only, AFTER the water heater. So, in other words, give the water heater unsoftened water.

 

If one feeds the water heater softened water, it's important to check the sacrificial anode rod regularly - I've read ever six months - and replace it if it shows 2/3 or more wear. It's probable your anode gave out which allowed the water to rust out the metal parts of the water heater.

 

I don't agree that hard water minerals have a protective function if they precipitate out inside the water heater. However it's important to keep the water going into the house on the alkaline side. Acidic soft water is too corrosive, and will eat not only the water heater but also copper plumbing.

 

 

[kb0nes]

If your old unit lasted 17 years you did fine. Adding a routine purge and replacing the anode rod at ~ half life may buy a few years. The powered anode is an interesting idea, but I'm not sure it is really worth it. The tank will eventually fail and you could buy about 3 or 4 standard anodes for the cost of a powered one. The powered titanium anodes are mostly an advantage for those that have water chemistry that reacts with standard anodes to create odors.

I don't buy the idea that ion exchange softening of water makes the water more corrosive to plumbing. The calcium or magnesium or other hardness ions are replaced with sodium ions. The ph of the water hasn't changed.

Dialing back the salt used during regeneration won't significantly change the amount of sodium fed to the home anyhow. The amount of sodium is based on the level of hardness in the untreated water since it is basically a one for one exchange. During regeneration most of the salt flows down the drain during regeneration and the bit that remains is rinsed from the resin bed before the softener returns to service.

 

[sudsmaster]

From link:

 

In water that is soft, corrosion occurs because of the lack of dissolved cations, such as calcium and magnesium in the water. In scale forming water, a precipitate or coating of calcium or magnesium carbonate forms on the inside of the piping. This coating can inhibit the corrosion of the pipe because it acts as a barrier, but it can also cause the pipe to clog. Water with high levels of sodium, chloride, or other ions will increase the conductivity of the water and promote corrosion. Corrosion can also be accelerated by:
1) low pH (acidic water) and high pH (alkaline water)- For high alkalinity water - it is possible that a chemical scale may form that would help to protect against corrosion, but if a bacteria becomes established the scale, such as SRB (sulfur reducing bacteria), you may experience a problem related to Microbiologically Induced Corrosion or MIC;
2) high flow rate within the piping can cause physical corrosion;
3) high water temperature can increase biological rate of growth and chemical corrosion;
4) oxygen and dissolved CO2 or other gasses can induce corrosion;
5) high dissolved solids, such as salts and sulfates, can induce chemical or bio-chemical corrosion;
6)If the mass ratio (CMSR) of chloride to sulfate is > 0.2, but < 0.5 there is an elevated concern, but if the CMSR is > 0.5 and the alkalinity of the water is less than 50 mg CaCO3/L the concern should be significant;
7) corrosion related bacteria, high standard plate counts, and electrochemical corrosion can result in pinhole leaks and isolated corrosion and aesthetic water quality problems,  and
8) presence of suspended solids, such as sand, sediment, corrosion by-products, and rust can aid in physical corrosion and damage and facilitate chemical and biochemical corrosion.

If it is necessary to flush or run your cold water in the morning for a few minutes before you drink because the water has a bitter taste, YOUR Water is probably CORROSIVE. If you see blue-green stains in your basins or some staining along the joints of your copper piping, YOUR Water is probably CORROSIVE. As corrosive water stands or seats in pipes or tanks, it leaches metals from the piping, tanks, well casing, or other metal surfaces that water is in contact.  If you see pink standing on the waters edge - this may not be corrosion, but pink bacteria.  Pink bacteria is an airborne bacteria.

Corrosivity

Corrosive Water Corrosivity Copper Lead Nickel Zinc Bitter Tasting Water Blue Green Staining Water Testing Treatment

www.water-research.net

 

[johnb300m]

Wow, this stuff really is news to me.
My grandparents used to have softened water, gas water heater and copper plumbing, and I don't ever remember any of those going bad or corroding.
Nor in my aunts' house right now that was built in the 70s. It's always had softened water its entire life since it's on a well.
They have high iron, but their old water heater lasted almost 20yrs, and they put a new one in several years back.
I know we're all supposed to flush our heaters out annually, but I don't know anyone who does that LOL.

This whole 'soft water killing water heaters' thing is NEWS to me for sure. I've always heard that hard water is the death knell to water heaters because they scale up, become less efficient, and then run longer and hotter in order to heat the same water to the desired temp.

I've also never heard of anodes in gas water heaters.
Do they have them?
I'm well aware of anodes in electrical heaters, which are rare in my area.

 

[kb0nes]

I Google'ed "softened water corrosive" and I came up with a number of links which seem to dispel the idea that softened water is more corrosive then water that isn't softened (assuming ion exchange softening). It is likely true that some forms of naturally soft water are more corrosive then other water though.

http://www.ukwta.org/assets/NewFolder/Softened-water-is-not-more-corrosive-Rev2-1.pdf

In any case, if softening vs not softening your water were to make any difference in the life of the water heater tank, it would likely be pretty minor. The idea of dishwashing, laundering or showering etc. in non-softened water to me makes the idea of not softening the hot water a moot point.

 

[sudsmaster]

Yes, thanks.

 

The main problem with softened water is if the incoming water has a low pH and low buffering capacity. That is corrosive.

 

Still, sodium chloride and sodium sulphate have very low buffering capacity. Sodium bicarb, more buffering capacity. So I'm not 100% convinced that softening water doesn't affect buffering capacity and hence corrosion potential. Also it would appear that most of the literature that water softening is 100% harmless comes from the ... you guessed it ... water softener industry...

 

 

[washer111]

Rain water is often seen as rather corrosive.

That said - my gradfather's old farm house has had the stuff for 60 years (since new), cast iron "mains" pipes that still haven't given up the ghost (though one wonders).
His water heater, a solar unit, has sat upon the roof for about 30yrs now and has the beginnings of trees growing from it. As best I know, it still has the original electric boosting element too.

People in houses with lead pipes ought to be careful with rain water, pipe-descalers and maybe water softeners, which can sometimes trigger a corrosion process and pinhole leaks from the lead breaking down. You could also end up with lead poisoning, which isn't fun.

 

[johnb300m]

Ahh that makes more sense.
Seemed like my ph and alkalinity were fine anyway when I was trying to troubleshoot my old water softener for weeks with water testing kits.

 

[sudsmaster]

Anyone with lead pipes should replace them with copper, PEX, or even steel would be better.

 

Lead pipes are Roman Empire technology.

 

And we all know what happened there.

 

 

[askolover]

anodes

gas water heaters definitely have anode rods.  My new and old Rheem built units talk about them in the owner's manuals and I can see it screwed into the top. 

 

[petek]

When we had well water back in Alberta it was high in iron so I had an iron filter added which did a great job, no more rusty stains on anything.  We didn't need a softener really. They will remove some of the iron but not near as much as a dedicated iron filter, plus with the iron filter there's nothing to add, no clocks, timers etc,  the resin tank was still working fine on ours when we sold the place 13 years later.