Softener, Too small, what now?

[DetRack]

Hello everybody,

first of all, my name is Detlev, I'm a new guy around here. Still amazed at the amount of knowledge which I find in this forum - I think I should have found this place before I made my purchase of a water softener

I bought and just had my softener installed a week ago. Everything is working as desired, but now I have a nagging feeling that my unit was too small for our needs.

Our softener is a cabinet system which I bought online with installation-service. The vendor has a calculator, and the unit is the size they recommended.

Base numbers: Our hardness is 110mg/l = 11.5 GPG. City water, no measurable iron (<0.02 ppm)

The weekly water consumption is about 790 gallons.

In Germany, we use an "alien" concept: Mixing - the bypass valve has a precision needle valve to allow mixing of a controlled amount of raw water. The usual recommendation is to aim for a mix of 50mg/l = 5.2 GPG. The value gets measured with one open faucet. So, in fact the unit will only soften 430 gallons per week.

The unit has 8l of resin (0.28 cubicfoot) and a Clack WS 1 CI valve. I guess these small units aren't even fabricated for the US market.

Capacity-claims are based on 200g/l = 12lb/cubicfoot. Based on that, the unit is sold for a weekly capacity of 8800 grains.

I guess the unit is adequate as long as we use the "mixing" function for 5.2 GPG water.

Now, we tried completely softened water (no mixing) for a few days and the family actually enjoys the difference. Another advantage is that I actually measure 2GPG hardness in hot water, a sign that the unit actually dissolves old limescale.

At 11.5 GPG and 790 gallons =

Now, what should I do? Use it as-is and see how long the unit lasts, or try to sell it and get a larger one?

From the economical side, I lean to use it as long as it lasts. What do you recommend?

Best,

Detlev

Fwiw, if you wonder about the odd bypass valve:

https://www.leyco.de/handel-handwer...eidearmaturen/bypass-und-verschneidearmaturen

 

[Reach4]

Now, what should I do? Use it as-is and see how long the unit lasts, or try to sell it and get a larger one?

The market in used water softners is usually not good. You could try to get a buyer before making the swap. Maybe you could find a person that would find your discounted unit to be worthwhile. You could also check the dealer to see if he would upgrade you for a reasonable amount. Incidentally, with city water, you should be using 10% crosslinked resin.

I did not check your math. If you want that, let us know. You can just let the softener regenerate more often by decreasing the capacity setting-- by approximately a factor of 0.5. Each night the softener checks to see if there is enough capacity remaining to make it through the next day. If not, it regenerates. Thus you could leave almost a day of capacity unused. That is where the salt-inefficiency of an undersized softener comes from. You can do the math on that for the trade-offs. I see you use a Mac.

You could manually intervene. You could set the reserve smaller than reality, and then manually trigger an early immediate regen at a time that fits your schedule. For example, if your remaining displayed capacity is low as you are ready to leave for work, then trigger an immediate regen. This would have gotten you though your morning showers. So in effect, you are gaining some finer granularity on time, but you have to do that extra chore.

 

[Sponsor]

 

[Bannerman]

Our hardness is 110mg/l = 11.5 GPG

As 1 gpg = 17.1 mg/L, then 110 mg/L hardness converts to 6.43 gpg and the 50 mg/L design hardness leakage converts to 2.92 gpg.

 

[Bannerman]

Small capacity softeners such as the one you purchased, seem to be the norm in Europe. Assuming larger units are actually available, how much additional capacity may be obtained?

Most 1 cubic foot (ft3) resin is generally considered to have 32,000 grains maximum capacity when manufactured. To regenerate the total capacity is not truly realistic due to resin wear and losses and would require 20 lbs (>9 Kg) of salt each cycle. A realistic maximum usable capacity will be usually 30,000 grains using 15 lbs salt.

As your current unit contains 8 Litres resin which is 0.28 ft3, then the maximum usable capacity should be 30,000 X 0.28 = 8,400 grains when regenerated with (15 lbs X 0.28)= 4.2 lbs (1.9 Kgs) salt.

The chart below shows resin capacity when using 10 lbs per ft3 or 15 lbs per ft3. As 12 lbs per ft3 is not indicated, I will estimate 28,000 grains when using 12.5 lbs salt, so for 0.28 ft3, this calculates as 7,840 grains when regenerated with 3.5 lbs (1.6 Kgs) salt.

Your estimated 790 gallons/week X 6.5 gpg (6.43 rounded up) = 5,135 grains hardness per week.

With approx 7,840 usable grains capacity available / 5,135 = 1.5 weeks approx between regeneration cycles. This does not assume any hardness leakage through the 'odd bypass valve'. As any hard water mixed in after the softener will not decrease the softener's capacity, the frequency of regeneration will likely be closer to 2 weeks if some hard water is mixed in after the softener.

While your low capacity softener will not offer the same salt efficiency as a larger unit unless the programmed capacity is drastically reduced, it appears to be a reasonable size for 790 gallons (2,986 L) weekly consumption and 6.5 gpg hardness.

https://terrylove.com/forums/index.php?attachments/resin-chart-jpg.53316/

 

[DetRack]

Thanks a lot!

Actually, I did the math in the metrical system and goofed when I converted.

In Germany, all vendors do a capacity calculation for 200g/l, that's a little more then 12lb/cubicfoot.

The common calculation of thumb is that 8l of resin at 200g clean 32°dH from 1000 litres. Looking at the basic conversion, that is 33.365 GPG by 263.15 gallons ≈ 8780 grains. For a cubicfoot, that amounts to 31081 grains.

My valve is factory set for 1.6kg (≈12lb/cubicfoot) and the stated capacity, auto regeneration at 2am, automatic reserve capacity, 10 days.

In Germany, city water is never chlorinated. So in my understanding standard resin seems to be ok.

I agree, selling the used unit would burn money. My priority should be to reduce wear on the machine. Estimated cost of salt is 20-25€ per year, no real issue.

I understand the factory settings are for peak performance at high salt. Using full softening, I will use that within 7 days. What would be settings that enhance system life?

 

[Reach4]

I went ahead and did some math. At only 790 gallons per week (very low), and 10 lbs/cuft salt, I would expect a capacity of around 7600 gallons, and with H set to 12 (11.5 with some compensation) about 5.6 days. That is better than I expected. Regenerating every 5 days is pretty efficient.

Note that water utilities, if they quote a hardness number, tend to quote an average rather than worst.

Here are other salt doses that could work. Your 10 seems reasonable considering your small tank, but 8 would be reasonable too but regen a bit more often.
lb/cuft ; C= (*1000 grains)
6 ; 5.6
7 ; 6.2
8 ; 6.7
9 ; 7.2
10 ; 7.6
11 ; 7.8
12 ; 8.0

 

[Bannerman]

My valve is factory set for 1.6kg (≈12lb/cubicfoot) and the stated capacity

There are default settings programmed when the valve is manufactured, but in North America, it is the installer's responsibility to adjust those settings as appropriate for the water conditions where the equipment is to be installed. In other words, the settings your unit was programmed with when it arrived, may not necessarily be appropriate for your specific water conditions and so, may need to be reprogrammed as appropriate.

 

[DetRack]

Thank you for all your help Converting between Germsn and US metrics is a bit nightmarish for me. German degrees are supposed to be 10mg of CaO or 17.8mg of CaCO3 per litre, and the conversion via ppm is absolutely confusing.

My second attempt was hopefully correct, and it also allows an easy backwards calculation from US capacity in grains to °dHm³ I used your number for 12lbs and came up with a german softening capacity of 29.17, that's 10% below manufacturer claims. The valve is now set to 29 instead of 32, and I increased the salt from 1.6kg to 1.7kg. I hope that's a safe margin even for full softening. At that rate, even full softening takes only 3-4 bags per year. That's absolutely fine. Salt pellets are cheap here at 9-10€ per bag.

should there ever be an issue with the unit, the new one will get double capacity. Looking around, the readily available cabinets go up to 25l, close to a cubicfoot. Bigger than that is only available with a seperate tank and targets commercial use.

Again, thank you for your help

 

[ditttohead]

In the US we rarely use the blending valve. We also use a very efficient salt setting which basically allows for some hardness leakage, but usually only 10 ppm on the high side. Ultra high efficiencies require larger units than low efficiency designs.

Softer water is much nicer than "sort of soft".

Here is a great article explaining the true differences between actual soft water and "Euro-soft".

http://wcponline.com/2012/03/05/soft-soft-water/

 

[DetRack]

At the moment, I am inclined to stay With fully softened water. Cost is not really an issue, as our salt consumption isn't that high anyway.

An additional benefit: By measuring the hardness from hot and cold water, it is clear that the soft water dissolves limestone from the boiler in our central heating. While I don't expect full descaling in a short time, it's comfortable to know that the boiler is getting cleaner. Having the whole unit replaced is one of those 10K+-events in life that everybody avoids whenever possible.

 

[Reach4]

Detlev, if you keep an eye on the count-down display, once you detect excess hardness, think about what settings would have made the display be down to zero at that point.

This would usually be done by an increase in the hardness setting.

 

[DetRack]

Will do, good advice!

 

[Reach4]

Here is a formula for you (use any units you like):

countdown_display_volume= C/H-Volume_used-Reserve

where C is resin capacity, H is hardness, Volume_used is what the metering says has been already been used, and Reserve is the amount water estimated to get you through the next day.

 

[DetRack]

Thanks again. I decided on the next steps. First of all, I calculated values for 10lbs: 1.3kg (rounded up) and 26dhm capacity and entered them. I messed quite a bit in the last days. So, the next step was to schedule a regen for tonight so I have a known starting point for the new settings.

I just found the diag and history menu on the unit where all the relevant performance data is saved. Fun fact: While logged water is only 2,400l = 632 gallons, the reserve capacity was calculated in the range of 900l. I think that's a result from my repeated changes of capacity and salt in the OEM mrnu. If i understand the manual correctly, the diagnostics are reset everytime I enter the OEM menu.

 

[Reach4]

I suspect you are right on the resetting to a pessimistic reserve amount when you make some changes. I would not think changing H should do that, but I don't know what actually happens.

I think you can opt to not have the reserve automatically calculated, but can choose a number. I don't know the settings for that on your controller. I did that on my Fleck 5810 softener because I was impatient. But in my case, the time between regenerations was much larger, and that reserve number was less significant. For most people, the automatic would be the better choice.

On the Fleck, the automatic method keeps track of the use during the various days-of-week, and knows to allow for weekdays that you tend to use more or less water. Your controller may do the same.

 

[DetRack]

The clack manual has a chapter on the diagnostics. They say that resetting the diagnostics (reserve is there, and actually caries by day of week) is done by pressing the combination that opens the OEM menu. They should state this in the OEEm chapter, too 8)

i think the next action is to sit and wait for two weeks so the unit can learn and the cycle stabilizes.

 

[WorthFlorida]

Detlev, I cannot understand the use of the mixing valve? It does not take much untreated water to have an effect in the soft side of things. I had an O-ring slip off on the bypass valve and felt like no soft water at all. I guess there are some that don’t like the near zero grams of hardness (slippery) feel. With my water softener, since I had a basement, I ran a hard water line to the kitchen sink since I didn’t like it for cooking. It turned pasta to paste.

 

[DetRack]

Well, there are many regional peculiarities everywhere in the world. In Germany, there have been cases where completely softened water caused old galvanized steel plumbing to leak. Those were probably cases where the old calcite was acting as a sealant for rotten pipes, but people feel safer with 5 Gpg than with completely soft water. In fact, the national premium brands like Gruenbeck and Judo recommend 3-6 Gpg as the optimum.

Anyway, the bypass valve is needed in the main line, and the inclusion of a needle valve in the bypass does not add much to the cost.

Atm, I'm using fully softened water and enjoy it. My wife says there is no difference.

These peculiarities exist everywhere. Seeing that you are from Florida: My municipal water supply is entirely made from PEHD in DN50 with brass compression fittings up to the meter. This would not be up to code in FL, and every renowned plumber in Florida would swear the pipe is unfit for pressurized lines. It will outlive me. Also, my irrigation well is just 36ft with a water table at 15 feet, but I enjoy a submersible pump anyway - 30% less energy, and it's completely silent. I couldn't stand a Goulds 1.5hp pump at 4am in the morning. In the US, nobody uses submerged pumps as long as the watertable allows suction pumps.

You get my point?

 

[Reach4]

Anyway, the bypass valve is needed in the main line, and the inclusion of a needle valve in the bypass does not add much to the cost.

A number of people think they would dislike soft water due to a slippery/slimy feel. Your needle valve would let them dial in what they wanted. I suspect that most would dial the unit softer with time.

In the US, nobody uses submerged pumps as long as the watertable allows suction pumps.

Not nobody, but in warm areas, such as Florida, a lot. Yes, there seem to be areas where people don't even consider a submersible pump. However some have 2 inch internal diameter wells or driven sand points, and those won't fit a submersible. In colder areas for year-round use, more have 4 inch or more wells and use a pitless adapter. So submersible is common there, even for a shallow well.

Some even use a submersible pump horizontally in an above ground cistern. A flow inducer becomes particularly important then. And I suspect the savings of the submersible pump are even greater than your 30% estimate. Of course your pumps are more efficient than ours with your 3-phase power.

 

[Bannerman]

My wife says there is no difference.

Detlev, even with the blending needle fully closed to obtain fully soft water, I suspect your soft water will contain some amount of hardness in actual use.

One cubic foot of resin will typically support up to approx 9 gpm (34 Litres/minute). When the effective service flow rate for the resin quantity is exceeded, then there will be lower contact time and the resin can not perform rapidly enough to remove hardness so some amount of hardness is likely to leak through and continue to rise as the flow rate continues to increase. Since your system contains only 0.28 ft3 of resin, the service flow rate will be significantly lower and so more easily exceeded in regular use.

I don't know how fast your family uses water or the flow rate in which your 0.28 ft3 softener can fully remove hardness. If the service flow rate were to decrease in proportion to the resin quantity, then 34 Lpm X 0.28 = 9.52 litres/minute should be the service flow rate directly following regeneration, but I suspect the service flow rate may be less in actual practice and will further decrease as the resin's capacity is consumed.

Although a sample obtained from a slow flowing faucet may test at <1 gpg, faster flowing water may feel significantly harder.