Help me with Twin Tank Softener Size please

ME62August 27, 2013

My Kenmore Ultrasoft 250 water softener has a leaking brine tank so it is time to replace after 10 years service. I have overresearched softeners and am now confused after having a softener expert do a house call.

Water usage is 267 gallons per day average but it is more of a continuous run instead of all at once. We really never use shower and washing machine at same time.

Hardness is 41 grains per gallon.

Water supply is city well. No iron.

I would like to get a twin tank softener put in because we do not have 2 hours of no use to be able to regenerate.

Expert recomended a Fleck 9100SXT 48,000 grain softener that would regen every 4.5-5 days and use 100# of salt a month.

Please let me know your thoughts.

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Is your expert recommending a twin 9100 with 48k in each tank (total resin volume of 96k) or 24k in each tank (total of resin volume of 48k) cause his #s don't add up and indicate really low salt efficiency.

To get 48k hardness removal capacity from 1.5 cubes of resin you have to regenerate at the max salt dose of 15 lbs/cu ft of resin or 22.5 lbs of salt for 1.5 cubes which is NOT salt and/or water efficient. You will regenerate every 4.3 days and use 168.75 lbs of NaCl every 30 days. That's a lot of salt and wasting a lot of water.

Let's size this softener correctly...

hardness=41 gpg. So how about TDS?, pH?, Manganese? Chlorine?

# of people in in home?

# of bathrooms?

Any high water use appliances like an uber-shower or Jacuzzi?

Diameter of the plumbing at the softener install location?

SFR? If your main bath tub has a common two handle faucet using the bathtub as the measuring point, open BOTH the hot and cold water faucets completely open. Place a 1 gallon container under the faucet and measure the amount of time it takes to fill the container in seconds

This post was edited by justalurker on Tue, Aug 27, 13 at 17:22

    Bookmark   August 27, 2013 at 3:32PM
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I assumed a 48K for each tank but I should clarify. His option B was a single 48K.

His conductivity tester was not accurate but I think he guessed at 6,000 for TDS.

ph was normal

Maganese - I don't know

Chlorine from city water inspection was 0.5ppm highest level detected.

Only 2 adults and 1 child in home.

2-1/2 baths

No high use fixtures.

1" copper pipe

I would have to check SFR but tub and shower has a single handle. 10 year old home so I don't think it is anything with a high flow rate

    Bookmark   August 27, 2013 at 5:34PM
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TDS of 6000?

If tub has a single handle go to an outside hose bib and bypass your softener.

Average water use per day is recognized as 60 gpp per day and that # has proved to be accurate so three people would be 180 gpd but let's use your # of 267 gpd. Be aware that if your 267 gpd proves inaccurate that all the calculations will be wrong and the softener will not be sized correctly.

267 gpd x 41 gpg = 10947 grains of hardness per day to be removed. So, to go 5 days you'd need a hardness removal capacity of 54735 use 2.0 cu ft of resin using 10 lbs/cu ft or total of 20 lbs of salt for 2.0 cubes of resin and that is 6 regenerations per 30 days using 120 lbs of salt. Better huh?

You want a Fleck 9100SXT (with 1" meter) with bypass using 2 cu ft of 10% cross link brand name resin in each 12x48 resin tank. Demand a gravel underbed for the resin tanks and make ABSOLUTELY sure you get Fleck brand top and bottom baskets not the cheapo junk baskets.

You won't want your expert to program the softener cause he/she has already shown they don't know how to program and size for efficient operation. I'll give you the programming and you have them do it .

You can down load a manual for the Fleck 9100SXT and get familiar with the valve and programming.

    Bookmark   August 27, 2013 at 5:57PM
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Tub provided a flow of 3gpm at the spout. I would think this is the max flow rate we use at any given moment as we typically run the shower head which would restrict that flow. 267 gpd was based on using 8,000 gallons per month. (Wife takes hour shower and is home all day.)

Because of our low flow, would we get channeling issues with a larger softener?

120# of salt seems to be much more than what my Ultrasoft 250 was using. I think it only used around 60#.

Sorry about my TDS #. I can't remember what was said and didn't research what was normal. I do have a whole house filter installed after water line comes in house. Change the filter regularly. Expert recomended removing filter cause solids would still get caught in bowl and softener would filter the rest.

    Bookmark   August 28, 2013 at 8:07AM
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Nice of you to mention the whole house filter now... more than likely it it a 10" filter and has insufficient flow rate and impedes the SFR. Get rid of the filter housing unless you have visible sediment and then get a properly sized filter canister.

Thing about pre-filters is that unless a pressure gauge is installed before and after the housing to see the pressure drop across the filter no one can know when to change the filter.

Forget the tub for SFR if it has a single handle valve... you won't get full flow. 3 gpm is far too low for a house with 1" water service. We need to know the SFR to size the softener so hardness won't leak through the softener at peak SFR. Go outside to a hose bib and try the test with the SOFTENER BYPASSED and the FILTER REMOVED FROM THE HOUSING.

Your Sears softener used more than 60 lbs of salt per month if it was treating 41 gpg water @ 267 gpd and was set up correctly and operating properly or hard water was leaking through almost all the time. Ever test your water after the softener for hardness?

Your Sears Ultrasoft 250 was a 1 cu ft softener and at max salt dose of 15 lbs that is 30k hardness removal capacity so with your stated 41 gpg and 267 gpd it would be a regeneration every 2.7 days and that would be 11.1 regenerations every 30 days and at 15 lbs salt / regeneration that is 166 lbs of salt every 30 days. And that's not setting aside any reserve capacity which you have to do with a single resin tank softener.

The numbers don't lie. If you don't like the numbers based on the info you provide then you should make your decision based on your experience and knowledge sizing softeners and let us know what you decide so we can all learn.

This post was edited by justalurker on Wed, Aug 28, 13 at 10:45

    Bookmark   August 28, 2013 at 9:53AM
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First I would like to thank you for your feedback as I have been reading your posts to others who have had questions here.

I will bypass the whole house filter and test the hose bib gpm tonight and reply with results tomorrow.

The Ultrasoft 250 was set at 45 in the digital display but I don't know what salt dose that equals. I do know that I wasn't using (4) bags a month. Maybe between 1 and 2 bags per month. I do think it was regenerating around every 3 days. Expert tested water at kitchen sink and it was 4gpg but I think we allowed water in system by using during regeneration so that is a flawed number. (Why I was leaning towards a twin tank.)

Does using water at a rate of only 1-3 gpm cause any concern when sizing the softener?

    Bookmark   August 28, 2013 at 11:58AM
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To repeat... again... go outside to a hose bib and try the test with the SOFTENER BYPASSED and the FILTER REMOVED FROM THE HOUSING or bypassed if there is a bypass at the filter.

There is no way under the laws of chemistry and physics that your Sears softener was ACTUALLY treating almost 11,000 grains per day and only using 80 lbs of salt doing 10 regenerations a month REGARDLESS of what setting you inputted into the control valve... simply NO WAY. You may have assumed it was treating all your hardness or thought it was treating all your hardness, but that don't make is so. You can argue and debate with me but unless you routinely tested your softened water to KNOW that it was ZERO hardness you don't know, but the numbers don't lie. Arithmetic is arithmetic and chemistry is chemistry and physics is physics.

An industry standard 1 cu ft softener requires a minimum of 2 gpm to regenerate and your Sears was 1 cu ft and a packed bed at that so if you really have only 3 gpm SFR then you are right on the edge and you need a larger softener than 1 1 cu ft unit so backwash SFR requirement goes up.

You have an argument for every fact I provide so you must know more about this than me so show me some numbers and calculations that support what you say.

One of us came to this forum asking for help... and even said please. One of us is trying to provide that help and is typing the same thing multiple times and being told that what they say is wrong based on the experience(?) of the other. I really hate typing and not getting anywhere so I have nothing to add to this thread.

When you have ZERO hardness all the time then you have soft water.

Please let us know what you decide and how it works out for you.

This post was edited by justalurker on Wed, Aug 28, 13 at 12:41

    Bookmark   August 28, 2013 at 12:25PM
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I'm not sure what I said to make you think I was arguing with you. I'm asking questions to try and make sure I get the correct softener since I have a high hardness number and high daily usage that comes from long sustained use instead of high peak use. I may and probably do have hard water leak through with existing softener. I'm just relaying the information I do know. No need to get upset.

    Bookmark   August 28, 2013 at 12:46PM
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EVERY answer I posted was specific in leading you toward EXACTLY the correctly sized softener for your water usage and conditions (limited as they are) as you posted them and explaining how I arrived at that conclusion using simple arithmetic. If you can do simple arithmetic I posted numbers that show what the correct size softener should be and why your Sears was wrong. What could make you more SURE than that? Your expert(?) spits out 48k with no facts to back it up and you believe him/her?

Neither your water conditions nor your water usage is unique but having a softener that was the wrong size is VERY common and people come to these forums to correct that often. You are in a large group of people who don't know what they don't know about water treatment and bought the wrong softener or simply inherited someone's wrong choice of water treatment equipment.

I don't care what softener you had before, how it was set up, or how you think it was working... you asked for help correctly sizing a new softener and YOU decided it should be a twin resin tank softener and YOU determined the water use and you got the specific recommendation you asked for.

If you came here wanting an education in water treatment then I'm not your guy. I do HOW questions not WHY questions. I can tell you what we need to know to correctly size and set your softener for efficient operation and then determine both for you and you get that for free.

When you chose to determine your own water usage and conditions and provide limited water condition details then that's what values get plugged into the formula.

I'm not the least bit upset cause my softener works great and I have 45 gpg hard water. I have nothing to gain or lose from what you buy. Do what you like with whatever information you choose to believe.

This post was edited by justalurker on Wed, Aug 28, 13 at 15:22

    Bookmark   August 28, 2013 at 1:57PM
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Had the expert install a Fleck 9100SXT with 1.5 cu ft per tank (which is 48K each) and couldn't be happier so far. Total price was the same as what I could buy from a reputable online dealer and I have all the bells and whistles. Water is much better than when the Kenmore was in service. Now it feels like we have luxury water. HA HA.

I am curious as to how much salt we will use but we set it up to regen more often at a lower salt dose. (I would rather pay for wasted water than carry an extra bag down the stairs.)

I was very skeptical of all the advice online especially because it only came from a couple of people. Thankfully I found an honest supplier that serviced my area.

    Bookmark   September 25, 2013 at 2:01PM
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