Purchasing new softener + GAC - help sizing and general advice?

[Kent Leigh]

Hi, I've been doing a lot of research on this investment and have boiled it down to the following. I would appreciate any help or advice you experts might give, especially on sizing, valve choice and my strategy to treat the water problems I have. Purchase horizon is within the next 7-10 days.

Here goes:

Single family home, 4400 sq ft (1" PEX), 4.5 baths on city water, 4 people (2 adult, 2 children). Typical water use is under 200 gallons a day (55 per person). Max concurrent usage is typically 2 showers at the same time, rarely even that.

Water test results:

Hardness: 10 gpg
PH: 7.4
Iron: .7
Chlorine: 3 ppm

Approach:

Fleck 7000 SXT 2 cft GAC (to treat chlorine) followed by
Fleck 7000 SXT 1.25 cft softener

I sized the softener based on some online sizing help. I figure 32k capacity is fine for max flow, but i wanted a bit of a buffer at 40k capacity.

Appreciate any feedback on this plan!

Thank you
Kent

[Gary Slusser]

You need to size using the max gpg of hardness in your city water system. You can find that in the company's Water Quality Report on their web site or by calling them. That assumes you haven't saved the one they must mail you each year.

The constant SFR (service flow rating) of a 32k (1.0 cuft ) is 9 gpm and just barely over 10 gpm for a 1.25 cuft. You will get terrible salt efficiency in either of those softeners.

You should click on the sizing link in my signature.

[Kent Leigh]

Hi Gary, I estimate my peak flow rate at 7 gpm and total hardness at 14 gpg. Hence, 32k rated/24k actual size for 8 day regen cycles at 8lbs per regen, or under 400 lbs of salt a year @ $100 cost. I am considering sizing max flow on 9.5 gpm peak flow rates (48k rated system, 36k actual) to account for more concurrent usage as the kids grow up.

The water supplier doesn't show hardness in the QA report, so I'll have to call them tomorrow to get that.

[Kent Leigh]

Hi again, ran the numbers for a low salt efficiency. At 1.5 cuft or 22k grains, I can regen the resin every 7 days using 5 lbs of salt. That should cut salt costs by 1/3rd saving around $30 a year (at $10 a bag per 40 lbs). Over 15 years, that's $450 savings for a bump in price (from 1 cu ft) of $40.

That's assuming 3080 grains used per day (4 people at 55 gallons a day at 14 total hardness)

Does that sound right?

[ditttohead]

The maximum flow rate is based on fixture counts, you have 4 bathrooms... I would recommend a larger system. Why not at least match the softener and the GAC tank at 2 Cu. Ft. each. That would be the minimum size I would recommend.

[Kent Leigh]

Hi Dittohead, I restrict usage today to two showers at a time with no dishwashing or washing machine going on. Don't ask me why (because i really don't know, maybe related to growing up and running out of hot water)! Do i still need to account for the 4 showerheads even though we run only 2 at a time at any one time?

Thanks!

Edit: Nevermind, the wife wants it sized to consider max flow rate of 12 gpm in case we have visitors or we change the shower configuration (more shower heads) down the road. 2 cuft is current thinking at this point.

[ditttohead]

The 2 Cu Ft. 7000 should do you well. I would recommend ordering the 61601 90 degree kits as well, it usually make the installation a little easier, and they are fairly inexpensive.

[Mikey]

Are there similar 90° kits for other Fleck valves?

[Gary Slusser]

Hi Dittohead, I restrict usage today to two showers at a time with no dishwashing or washing machine going on. Don't ask me why (because i really don't know, maybe related to growing up and running out of hot water)! Do i still need to account for the 4 showerheads even though we run only 2 at a time at any one time?

Thanks!

Edit: Nevermind, the wife wants it sized to consider max flow rate of 12 gpm in case we have visitors or we change the shower configuration (more shower heads) down the road. 2 cuft is current thinking at this point.

The 2.0 cuft is a much better choice, especially if the kids are quite young, as they grow older you may find you are running more than just two showers, and you get better salt efficiency.

I suggest a 5600 SXT on the softener with the plastic by pass valve. Gravel underbed and salt grid, 2310 safety brine valve in a 3" brine well and a 12" x 52" regular resin tank (not Vortech). That gets your softener back closer to the wall and the 5600 is much easier to work on than the 2510 or 7000 valves.

[ByteMe]

Edit: Nevermind, the wife wants it sized to consider max flow rate of 12 gpm in case we have visitors or we change the shower configuration (more shower heads) down the road. 2 cuft is current thinking at this point.

HA! Another man with a wife smarter than him!

[Kent Leigh]

Gary, I had assumed 7000 as i have 1" PEX feeding the current system. Wouldn't i lose more water pressure with a 5600? I just checked the pressure gauge and it reads 75 off the main line.

I think i'll have to reconfigure the entire system as I have outside sprinklers being fed after the in-house distribution (to faucets, bathrooms, and outside bibs), and then the water heater is fed last. ugh

Main -> house distribution manifold, including outside bibs -> sprinklers -> water heater

[Kent Leigh]

HA! Another man with a wife smarter than him!

LOL for sure!

[ByteMe]

Maybe it would be better to figure for maximum GPM of the house. This way if you ever added water use or sold the house and the new owner used a lot of water, your softener could handle it.

Wouldn't that be more like a 3 Cu ft system? So a 7000SXT.

[ditttohead]

For a 4 bedroom house, the 7000 would be the smallest I would recommend. A 3 Cu. Ft. may be more accurate on paper, but you have to consider the low flow efficiencies as well as the peak and SFR potentials. By exceeding SFR very rarely, and using the peak as the actual capability of the system, the 2 or 2.5 cu. ft. system would be a better choice due to its low flow efficiency, which is what the house will see 95% of the time. Check out the chart below for more information on service flows, both low and high, and potential peak flows. Again, exceeding the recommended flow on a rare occassion does not damage the resin in any noticable way. If you constantly run the system above the recommendation, it will damage it over time. This is a legitimate concern for commercial applications when the system is undersized, or sized to the peak and not the recommended max flow. Residentially, the difference may be 15 years of resin life instead of 18 years... if you exceed the recommended flow on a very regular basis. Also, the 5600 is not recommended on any larger than a 12" softener tank.

[Kent Leigh]

Any concern with the GAC at 2 cu ft. when sizing for 12 GPM peak flow rate?

On the softener, I will rarely exceed max flow rate of 7 GPM. I anticipate in the next 5 years that I'll exceed 7GPM twice a year, and not to exceed 12 GPM at all.

Regarding sizing for the house for future buyers, I plan on taking my softener and GAC with me if I ever sell!