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Sounds to me like I read that same document.
The concerns I remember seeing where one of two main themes; bacterial growth (I read somewhere that softeners outside where more prone to this) and resin fouling (mostly iron). I don't know the truth of either of these.
*edit* I think the 5600SXT defaulted to a 14 day DO.
Both have validity and both are easily remedied. It has become much more common in the past 10 years to regularly sanitize resin with a small amount of bleach in the brine tank annually. Chlorine damage is cumulative, annual sanitizing has very little affect on resin, considering the 40,000 - 100,000 gallons of water the average softener sees in a year. A well system that is not chlorinated should definetly be sanitized annually, or softeners on chlorinated supplies that are pre-treated with GAC to remove the chlorine.
Iron... this always starts some weird debate on this site, and it gets tiring going through the same old and tired arguments. Several on this site agree that softeners can treat iron, but with the modern medias available, and simplified equipment, and the innefficiencies of using the softener as an iron filter, alternative treatment methods of removing iron should be considered. A softener that is used for iron removal has to use a compensated hardness, basically an 85:1 ratio, this is not efficient, but it definetly works. Manganese has a 425:1 efficiency ratio when done on a ppm basis. Both of these common water problems are easily treated with some additional costs up front, and some additional equipment. Water softeners that are used for iron removal should be regenerated often, and with higher salt doses as you read in the article. Other methods include chemical drip systems (acidifying the brine solution with phosphoric acid), and regular chemical cleaning of the resin with acids.
It looks like you understand the common sense part of it. Now to throw another idea your way. Channelling is not an issue in most properly designed resin based systems for a simple reason, the media is round. Irregular medias like GAC, filox, filter-ag, calcite, mag-ox etc should be backwashed more regularly due to the shape of the media. That is why many resin based systems that are single use do not have a backwash valve and they are downflow. Irregular shaped medias tend to be upflow if they are not going to have a valve due to media compaction, and the potential for channelling. Consider the rack of balls at wal-mart, once they settle, they can settle no more, and the can never block water flow. Unless the balls pop (the crosslink structure of the resin fails and the medias fracture) The main requirement for this design is that sedimnet be removed prior to the resin. DI tanks, Arsenic removal resin, post RO polishing softener tanks, etc all designed for single use, and are designed to last for several years do not require backwashing.
Great questions!
I was also not 100% sure or confident about the low 3lb cu/ft salt dose, the old ways says 6lb minimum, some of the newer information says 4 or 3 lbs minimum. I'm worried that this low 3# dosage for 13K might cause media depletion and I also set the 8 day override with this media depletion concern in the back of my mind. I figured the meter at 13K would be maximum before a regen and that with my use that at 8 days the media would regenerate at about 8K use, before depletion could become a concern. Am I just fussing and worrying for no good reason? Or is a 3# dose good enough for my usage? Sometimes I'm just too fussy and I end up spending too much time on minutia...
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Originally Posted by ditttohead
But Dittohead, why would anyone believe what you say? After all you only have been in the industry for 20 years or so. :cool: Maybe if you bought yourself a motorizd trailer and settled into a Wal-Mart parking lot you'd be a little more credible ;) BTW, I frequently program for 30 days and even more when applicable and have NEVER had a problem doing so. Then again, I've only been at this for almost 40 years and sold my motorhome a decade ago. Too much noise in the parking lot LOL
LOL, 25+ years, Certified Water Specialist Level 6, Certified Installer, C-55 contractors license, Steam boiler operator, etc..., I am just a noob. :)
As to the 30 days... We have portable exchange tank systems that are on a 6 month route, never been a problem in a quarter century yet.
My own system is regenrated with 6 pounds of salt for many reasons. The main issue is my wifes hair. She is black, and her hair is unmanageable with any hardness in the water. I have tried the 3-4 pounds settings, she complains and goes to the beauty salon to get her hair done at $75 a trip. One extra bag of salt a year is lot cheaper than 12 Beauty salon trips a year.
Here is a great article on softness of the water. http://www.wcponline.com/pdf/1203Michaud.pdfAttachment 18039 A softener regenerating with 3 pounds per cu. ft. will have some bleed, this is normal and well charted. A softener regenerated with 6-8 pounds will have much lower leakage, but you will give up some of the efficiency. 6-8 pounds is still very efficient. See the attached chart above for detailed hardness leakage / efficiencies. As you can see, you will near the 1/2 GPG mark at 3 pounds of salt, this does not take into consideration end of run (the day or two prior to regeneration where leakage will be much higher).
It's all getting increasingly complicated, soon it will clear as mud...:confused:
I think it says here http://www.wcponline.com/pdf/0202brine.pdf to expect 9 to 10 ppm hardness leakage with a 3# salt dose, slightly more than 1/2 grain, not all that bad. They mention the Double Backwash advantage here: http://www.pentairwatertreatment.com...er%2042755.pdf
I might bump up the salt dose a bit to about 4lbs...
That is a great old article. It has a few minor items that some people would disagree with, but the article was written with generaliztions, not absolutes. So the arguments people have made to the article are usually based on unusual application methods, not on the 95% of common applications. The only way to avoid these people who are always looking to argue, but refuse to write articles themselves would be to write a book on the subject with every possible scenario... not really an article anymore.
Try 4 pounds of salt, but remember that you wont get the actual hardness leakage for several regenerations, and the leakage increases when the system nears regeneration. If you are happy with the water at 4 pounds, then keep it there. If you want it a bit softer, bump it up to 6 pounds, you will lose very little efficiency.
I take it that I should I also up the capacity, like to 20K if I decide to use 6 pounds? Or 15K with 4 pounds?
Quote:
Originally Posted by ditttohead
Correct, the capacity is based on the salt usage. As you can see, the efficiency goes down, but the quality goes up with higher brining levels. Up to 6-8 pounds is the most popular to balance the efficiency and quality.
Dittohead,
I understand the leakage vs amount of salt used for regeneration. But I have the SST60 resin that leakage should be about 4 times less than you state!
link; http://www.caitechnologies.com/image...pecs/SST60.pdf : see figure 6 and the chart below.
It seems to me that you are taking a very conservative stance on this (more about this in a new thread soon).
I've read all of what has been said here about regenerating resin except for the resin manufactures saying it was OK to go 30 days or even 6 months between regenerations as has been claimed here.
Fact, all city water and private well water has turbidity in it; some city waters have more than private wells, mostly due to the condition and type of their water distribution lines and their age.
Turbidity ( and bacteria etc.) buildup in a softener causes a loss of capacity and can cause a resin replacement long before it would have to be replaced if it had been regenerated more frequently. Like every 7-9 days. Kinda like an engine lasting longer the more frequently the oil is changed.
To help you understand the operation of your softener. Compare it to you going to fill up the fuel tank in your vehicle.
Then you drive X miles or X number of days and refill the fuel tank again. It is a 20 gallon tank, it takes 12 gallons to refill it the first time. You can calculate fuel mileage by dividing the miles driven by the gallons needed to refill the tank.
What happened to the other 8 gallons that were still in the tank when you refilled? .... your new softener starts out with 2.0 cuft of fully regenerated new resin = 64K of capacity... You use 13k in say 8 days and have the equivalent of another full day's reserve plus the balance of 64 - 13 = 51K. How many K do you have to regenerate to get full capacity, full capacity will be 60k?
The max is 60k and that is due to the resin being used and you'll not be able to regenerate it to 64k unless you use more than 15 lbs of salt/cuft, and even then it is questionable.
Now 60k takes 30 lbs of salt per regeneration. Looking at salt efficiency you calculate it the same as fuel mileage, 60,000/30= 2000 grains per lb of salt used but... if you only used 13,000 and want a salt efficiency of say 3333 grains per lb, you use 3.9 lbs (round to 4 lbs) per regeneration, that is not per cuft. AND the remaining 60,000 - 13,000 = 47,000 (or 47k), is still in the tank. The same as the 8 gallons of fuel in is your vehicle.
You program the K of capacity for say an 8 day service run plus the reserve and then the salt dose that is required to regenerate that K of capacity and set the calendar override for day 8 or a couple days longer.
The WQA says that a softener is working just fine as long as there is no more than 1 gpg (17.1 ppm or mg/l) of hardness in the softened water. I have sold softeners programed this way for many years without customer complaints or problems.
More frequent regeneration prevents resin problems in the future.
Thank you DH for taking the time to post so much useful information. I'm in the same boat as these guys, I sweat the details. I'm an engineer, it's not my fault, I was just born this way.
When discussing resin life, is there a rule of thumb such as a general number of cycles the resin is good for?
I am treating about 1ppm iron, so I'm regenerating on a 7 day schedule. I'm running 6lbs/cf but finding that my family doesn't use as much water as I thought we would. I could go probably 9 or 10 days from a capacity standpoint. I can't decide whether to drop the salt or stay as is with the logic that treating iron means weekly regens and higher salt for good resin life. The salt $$ difference is pretty insignificant but quantifiable, the resin life is not.
With 1ppm Iron you should keep the programming you are using. Salt efficiency (and water) is all very well and good but in actual dollar savings the diffenence isn't enough to worry about except for cronic penny pinchers.
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Originally Posted by MagKarl
Like you, I am pretty much the same way... and I find this technology interesting. I wish I could find more data to quantify an expected resin life. As is, I went with the SST60 resin to hopefully get a long resin life. The side effect being the SST60 specified data provided by Purolite suggests it is better all around by 15%-20%.
The SST60 resin is approximately double the cost of a high grade 10% crosslink resin. The lower leakage is beneficial for some commercial applications, but there is still a lot more to the story. Too much to go into here. If you can afford it, then it is a good resin. Will it pay for itself in salt savings? Not likely, sot of like a hybrid car. The ROI is so far out that it is difficult to justify. We only have a few customers that use it, we sell thousands of cubic feet of standard resin to the few feet of SST.
I would have used it in my own system, but... I was too cheap. :)