(206) 949-5683, Top Rated Plumber, Seattle
Page 1 of 2 12 LastLast
Results 1 to 15 of 23

Thread: Water softener sizing - what do I need?

  1. #1
    DIY Junior Member opto_isolator's Avatar
    Join Date
    Dec 2013
    Location
    Florida
    Posts
    15

    Question Water softener sizing - what do I need?

    Building a new house, bought a Hach hardness and iron test kit. No iron detected in the water, hardness shows 8 gpg. The house has 3 full baths, right now it's just my wife and I, but will have guests visiting every once in a while, and a kid in the next year or two. I've tried reading and understanding the various sizing web sites, but am not sure what size I need. I've read that most companies size based on "size" versus cu ft of resin. Others say that I need to calculate my SFR, and go from there - but doesn't give any method to calculate the SFR. I'd like to get a Fleck 7000 series, as I think this will fit the bill for the size of our house, but not sure of how much resin / size I need. Can anyone help?

  2. #2
    DIY Junior Member opto_isolator's Avatar
    Join Date
    Dec 2013
    Location
    Florida
    Posts
    15

    Default

    From what I'm reading - it sounds as if it may be good to go with a 1 cu ft resin softener, regenerating at 5-6 lbs of salt a week. This would provide reserve capacity for when it's needed - right?

  3. #3
    DIY Senior Member mialynette2003's Avatar
    Join Date
    Nov 2010
    Location
    Ocala, Florida
    Posts
    667

    Default

    The SFR is important if you are going to run ALL your faucets at the same time. When I say ALL, I mean every single water connection in the house. Most folks don't do this but may have a shower, washer and the dish washer going at the same time. So to size your unit, I would go by the days between regens. A 1 CF system set using the best salt efficiency will yield 20K @ 6 lbs of salt. So 20K/8GPG/2PPL/65Avg usage=19 days between regen. With a 1 day reserve, you will regen every 18 days. This is not bad unless the iron content is high which you said was not showing up. I take it that you are on well water?

  4. #4
    That's all folks! Gary Slusser's Avatar
    Join Date
    Aug 2004
    Location
    Wherever I park the motorhome.
    Posts
    6,790

    Default

    And a 1.0 cuft has a constant SFR of 9 gpm and when that is exceeded, the resin will not get your hardness down to 0 gpg. IOWs you get some hardness through the softener. IMO that's like buying a vehicle that won't start a couple times a week. Most shower heads are 2.5 gpm, faucets 2.0-2.5 gpm, washing machines 3-3.5 gpm, toilets 1-1.5 gpm.
    Gary Slusser Retired (= out of business)
    Click Here to learn how to correctly size or program a water softener.
    CAUTION, as of Nov 12 2013 all YouTube videos showing how to rebuild a Clack valve have an error in them that can cause damage.

  5. #5
    DIY Junior Member opto_isolator's Avatar
    Join Date
    Dec 2013
    Location
    Florida
    Posts
    15

    Default

    Quote Originally Posted by mialynette2003 View Post
    The SFR is important if you are going to run ALL your faucets at the same time. When I say ALL, I mean every single water connection in the house. Most folks don't do this but may have a shower, washer and the dish washer going at the same time. So to size your unit, I would go by the days between regens. A 1 CF system set using the best salt efficiency will yield 20K @ 6 lbs of salt. So 20K/8GPG/2PPL/65Avg usage=19 days between regen. With a 1 day reserve, you will regen every 18 days. This is not bad unless the iron content is high which you said was not showing up. I take it that you are on well water?
    Thanks for the reply! I'm actually on city water (Florida). With regards to the regen - is there any way to set the regen to once a week? I know that it would be less efficient since wouldn't be using the entire capacity of the 1 cu ft of resin. Would it cause any harm to do this? I've read that if you wait too long to regen, the resin could get channeling or have other issues.

  6. #6
    DIY Junior Member opto_isolator's Avatar
    Join Date
    Dec 2013
    Location
    Florida
    Posts
    15

    Default

    Quote Originally Posted by Gary Slusser View Post
    And a 1.0 cuft has a constant SFR of 9 gpm and when that is exceeded, the resin will not get your hardness down to 0 gpg. IOWs you get some hardness through the softener. IMO that's like buying a vehicle that won't start a couple times a week. Most shower heads are 2.5 gpm, faucets 2.0-2.5 gpm, washing machines 3-3.5 gpm, toilets 1-1.5 gpm.
    So you recommend .75 cu feet?

  7. #7
    DIY Senior Member Reach4's Avatar
    Join Date
    Sep 2013
    Location
    IL
    Posts
    1,260

    Default

    Quote Originally Posted by opto_isolator View Post
    So you recommend .75 cu feet?
    I am confident that is not what Gary was saying.

    Click on the "Click Here" in Gary's signature. Follow that as best you can. Then click the link at the bottom of that page that will get you to a special calculator.

    You are unlikely to open every faucet at the same time. Having some hardness get by occasionally is not so bad. I expect that you have neighbors that have no softener at all.

    Most controllers allow you to set up a regeneration every week (although mine is not one of them). Many allow you to regenerate when you have used up enough capacity that you may exceed capacity by waiting a day, but set a maximum time between recharges that will occur even if you have not used any softened water at all.
    Last edited by Reach4; 12-20-2013 at 08:44 AM.

  8. #8
    That's all folks! Gary Slusser's Avatar
    Join Date
    Aug 2004
    Location
    Wherever I park the motorhome.
    Posts
    6,790

    Default

    If you use the entire capacity, which means you must set the salt dose at 15 lbs per cuft of resin you get 2000 grains of softening per lb of salt used, that's 30K in a 1.0 cuft (30,000 divided by 15= 2000). Compared to setting the salt dose to 6 lbs and getting 20K which is 3333 grains of softening per cuft of resin. That's an increase in salt efficiency of 1333 grains per lb. for every regeneration. I.E. if you went to a 1.5 cuft, at 6 lbs/cuft which is 9 lbs, you regenerate 30K where with a 1.0 cuft you need 15 lbs, or 6 more lbs for the same 30K of capacity. Plus, you never want to use all the capacity or you have to use 15 lbs per cuft to get all the resin regenerated again. It's like waiting to buy gas until you run out, it is not good to do that and can cause engine damage.

    Can you tell me how you got .75 ft out of what I said about SFR?

    Let's say you have 2 showers running (5gpm) and a toilet is flushed (1.5gpm) and someone starts the laundry washer (3.5gpm), your peak demand is the total of whatever is running so 10 gpm in my example. You would overrun the 1.0 cuft 9 gpm and not get all the hardness out of the water. And I'd be telling you that you should have bought a 1.5 cuft (12 gpm SFR) and set the capacity to the same as the 1.0 cuft and the salt to whatever lbs at 3333 grains per lb.. 2*60gals/day/person= 120* 8= 960* 8 days = 8640 rounded to 9K. That would be 1125 gals minus one day of 120 gals for the reserve with a meter setting of 1000 gals. 9000/ 3333= 3 lbs of salt per regeneration and that gets you a regeneration on average every 8 days with a constant SFR of 12 gpm. Then if you have a child, redo the math with 3 people at 60 gals per person etc..
    Gary Slusser Retired (= out of business)
    Click Here to learn how to correctly size or program a water softener.
    CAUTION, as of Nov 12 2013 all YouTube videos showing how to rebuild a Clack valve have an error in them that can cause damage.

  9. #9
    DIY Junior Member opto_isolator's Avatar
    Join Date
    Dec 2013
    Location
    Florida
    Posts
    15

    Default

    Quote Originally Posted by Gary Slusser View Post
    If you use the entire capacity, which means you must set the salt dose at 15 lbs per cuft of resin you get 2000 grains of softening per lb of salt used, that's 30K in a 1.0 cuft (30,000 divided by 15= 2000). Compared to setting the salt dose to 6 lbs and getting 20K which is 3333 grains of softening per cuft of resin. That's an increase in salt efficiency of 1333 grains per lb. for every regeneration. I.E. if you went to a 1.5 cuft, at 6 lbs/cuft which is 9 lbs, you regenerate 30K where with a 1.0 cuft you need 15 lbs, or 6 more lbs for the same 30K of capacity. Plus, you never want to use all the capacity or you have to use 15 lbs per cuft to get all the resin regenerated again. It's like waiting to buy gas until you run out, it is not good to do that and can cause engine damage.

    Can you tell me how you got .75 ft out of what I said about SFR?

    Let's say you have 2 showers running (5gpm) and a toilet is flushed (1.5gpm) and someone starts the laundry washer (3.5gpm), your peak demand is the total of whatever is running so 10 gpm in my example. You would overrun the 1.0 cuft 9 gpm and not get all the hardness out of the water. And I'd be telling you that you should have bought a 1.5 cuft (12 gpm SFR) and set the capacity to the same as the 1.0 cuft and the salt to whatever lbs at 3333 grains per lb.. 2*60gals/day/person= 120* 8= 960* 8 days = 8640 rounded to 9K. That would be 1125 gals minus one day of 120 gals for the reserve with a meter setting of 1000 gals. 9000/ 3333= 3 lbs of salt per regeneration and that gets you a regeneration on average every 8 days with a constant SFR of 12 gpm. Then if you have a child, redo the math with 3 people at 60 gals per person etc..
    Sorry - I am learning, I thought you originally meant that the 1 cu ft was overkill. But it sounds as if I may be better using 1.5 cu ft of resin, and set the capacity setting to 1 cu ft, and the meter to 1000 gal? Of course, that assumes the numbers for the SFR are correct - I'll need to measure those once we move in (closing soon!). I appreciate your help!

  10. #10
    That's all folks! Gary Slusser's Avatar
    Join Date
    Aug 2004
    Location
    Wherever I park the motorhome.
    Posts
    6,790

    Default

    The gpm figures I used are real figures. All softeners have an adjustable capacity. You adjust it by the number of lbs of salt used per regeneration. And all softeners allow changing the salt dose/lbs but some manuals do not tell the customer how to adjust the salt dose.

    Now if you have twins etc. and at times have the 3 showers running at once plus other water, the 1.5 cuft 12 gpm will be borderline and may be too small.
    Gary Slusser Retired (= out of business)
    Click Here to learn how to correctly size or program a water softener.
    CAUTION, as of Nov 12 2013 all YouTube videos showing how to rebuild a Clack valve have an error in them that can cause damage.

  11. #11
    DIY Junior Member opto_isolator's Avatar
    Join Date
    Dec 2013
    Location
    Florida
    Posts
    15

    Default

    Quote Originally Posted by Gary Slusser View Post
    The gpm figures I used are real figures. All softeners have an adjustable capacity. You adjust it by the number of lbs of salt used per regeneration. And all softeners allow changing the salt dose/lbs but some manuals do not tell the customer how to adjust the salt dose.

    Now if you have twins etc. and at times have the 3 showers running at once plus other water, the 1.5 cuft 12 gpm will be borderline and may be too small.
    Excellent - thank you!

  12. #12
    That's all folks! Gary Slusser's Avatar
    Join Date
    Aug 2004
    Location
    Wherever I park the motorhome.
    Posts
    6,790

    Default

    If you have any large full flow tubs or multiple shower heads, the 12 gpm of a 1.5 cuft will be too small.
    Gary Slusser Retired (= out of business)
    Click Here to learn how to correctly size or program a water softener.
    CAUTION, as of Nov 12 2013 all YouTube videos showing how to rebuild a Clack valve have an error in them that can cause damage.

  13. #13
    DIY Junior Member opto_isolator's Avatar
    Join Date
    Dec 2013
    Location
    Florida
    Posts
    15

    Default

    Quote Originally Posted by Gary Slusser View Post
    If you have any large full flow tubs or multiple shower heads, the 12 gpm of a 1.5 cuft will be too small.
    That's why I should check the flow rates with a 1 gal bucket, correct? If I add all up, they should give me the correct sizing I need based on what you just covered?

  14. #14
    DIY Senior Member Reach4's Avatar
    Join Date
    Sep 2013
    Location
    IL
    Posts
    1,260

    Default

    Consider that

    1. OP only has 8 GPG.
    2. Most people with 8 GPG don't have a water softener, and they get along fine by using more soap. I lived with 8 GPG of hardness 100% of the time and no softener for years with no real problem. The pipes did not lime up as far as I could tell.
    3. If OP passes 2 GPG of hardness through 1% of the time, it is very unlikely that any effects would be noticeable.
    4. The odds of having every water load on full at the same time are small.

  15. #15
    DIY Senior Member lifespeed's Avatar
    Join Date
    Apr 2007
    Location
    California
    Posts
    319

    Default

    Quote Originally Posted by Reach4 View Post
    Consider that

    1. OP only has 8 GPG.
    2. Most people with 8 GPG don't have a water softener, and they get along fine by using more soap. I lived with 8 GPG of hardness 100% of the time and no softener for years with no real problem. The pipes did not lime up as far as I could tell.
    3. If OP passes 2 GPG of hardness through 1% of the time, it is very unlikely that any effects would be noticeable.
    4. The odds of having every water load on full at the same time are small.
    It does not make sense to size for adequate SFR 100% of the time, it is more efficient to cover 99% of use cases. This might be two showers, a toilet and a washing machine. IMO, the 1.5 cu ft size would be a good compromise that will let you use many fixtures without exceeding the softener capacity.

    I would only consider the 5600 valve if your water main is 3/4". Any larger and you should use the larger 7000 valve, and of course there is no downside to using the 7000 on a 3/4" supply.
    Lifespeed

Similar Threads

  1. Water softener sizing
    By KMW in forum Water Softener Forum, problems, installation and reviews
    Replies: 11
    Last Post: 01-18-2014, 07:36 PM
  2. Sizing a Water Softener for growth
    By gak22 in forum Water Softener Forum, problems, installation and reviews
    Replies: 1
    Last Post: 08-23-2013, 08:46 AM
  3. Sizing and Spec Help? Water Softener
    By Freddi in forum Water Softener Forum, problems, installation and reviews
    Replies: 27
    Last Post: 08-16-2013, 01:07 PM
  4. Water softener sizing and system selection?
    By Killer95Stang in forum Water Softener Forum, problems, installation and reviews
    Replies: 19
    Last Post: 11-04-2012, 04:04 AM
  5. Please help with water softener sizing
    By ribs1 in forum Water Softener Forum, problems, installation and reviews
    Replies: 17
    Last Post: 06-11-2012, 09:19 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •