Help Programming a Fleck 7000 SXT

[batboy]

Details on the machine: 64,000 gr capacity, 2.0 cu/ft resin (standard resin)

I need some help setting up the machine to give me good salt efficiency. I probably won't be needing the whole 64k capacity right now.

I have 3 adults in the home using about 75 gal/ per day so that's 225 gal.

Hardness is 22 and I would like to regenerate every 9-10 days. I was thinking of setting the capacity of the machine at 40k. Am I thinking of this correctly?

Here is a link to the install guide and settings that I used for programming:
http://www.qualitywaterforless.com/v...k/70SXTINS.pdf


Current settings:

DF: GAL
VT: St2b (Standard Downflow/Upflow Double Backwash)
CT: Fd (Meter Flow Delayed)
C: 64k (capacity)
H: 22 (hardness)
RS: SF (Percentage Safety Factor)
SF: 20 percent
DO: 10 (Day override)
RT: 2:00AM
BW: 10 mins (back wash)
BD: 60 mins (brine draw)
BD: 40 (salt time setting)
RR: 10 mins (rapid rinse)
BF: 10 mins
FM: t1.2 - 1.5'' Turbine Meter (7000 default)

[Bob999]

I would recommend you go no more than 8 days between regenerations. This will also allow you to get better salt efficiency.

You need to know the size of the Brine Line Flow (BLFC) control on your control. There is usually a sticker on the back of the unit that identifies the size installed. I note the instructions you posted (the link) speaks of a .25 gpm BLFC. The amount of water added during brine fill determines the amount of salt and the capacity setting you should use. The practical max capacity is 60K with a 2 cubic foot unit and to get that capacity you need to regenerate with 15 lbs of salt per cubic foot (30 lbs total). Each gallon of water added during brine fill dissolves 3 lbs of salt. so to get 30 lbs you need 10 gallons of water. If your BLFC is .25 gpm then you would need 40 minutes of brine fill.

Dre you on city or well water? Is there any iron in the water--if so did you factor it in the hardness reading--each ppm of iron adds 5 grains to get compensated hardness.

If you were to set it up for an average 8 day regeneration, using your figures, your desired capacity would be 22 x 225 x 8 ~= 40,000 grains. To get 40,000 grains you need 6 lbs salt per cubic foot or 12 lbs and that takes 4 gallons of brine fill water--so if your BLFC is .25 gpm that would be a setting of 16 minutes. I would set the safety factor to 15 percent with these settings along with an 8 day override.

Also the second BD should be the second backwash and a relatively short time--certainly not 40 minutes.
We can talk about specifics once you answer the questions above.

[batboy]

The sticker on the back of the valve says .25 blfc. There is no iron in our water. This is city water. So for the 16 min setting, I would enter that in the length of the brine refill cycle correct?

[Bob999]

Current settings:

DF: GAL
VT: St2b (Standard Downflow/Upflow Double Backwash)
CT: Fd (Meter Flow Delayed)
C: 64k (capacity) 40K
H: 22 (hardness)
RS: SF (Percentage Safety Factor)
SF: 20 percent 15
DO: 10 (Day override) 8
RT: 2:00AM
BW: 10 mins (back wash) 6
BD: 60 mins (brine draw) 45
BD: 40 (salt time setting) Second BW 4
RR: 10 mins (rapid rinse) 3
BF: 10 mins 16
FM: t1.2 - 1.5'' Turbine Meter (7000 default)

I have entered recommended settings above in red.

If you have been operating the unit with the settings you had posted the resin has probably been partially discharged and to bring it back to fully charged and get best performance you should do two regenerations with 30 lbs of salt each --a 40 minute brine fill. Ideally there will be no water use between the two regenerations and you need to allow about 3 hours between the end of the first regeneration and the start of the second regeneration for the salt to dissolve and create a full strength brine solution. So if you initiate an immediate regeneration early evening then you can initiate the second (delayed) regeneration as you retire for the night.

[batboy]

Thanks for the pointers Bob. I changed the draw time to 40 min and did 2 regens. When I did this though, I changed all my settings to what you suggested and just changed the 16 - 40 for the draw time. I hope that was correct! I'll keep you updated on how the water feels.

[Bob999]

Thanks for the pointers Bob. I changed the draw time to 40 min and did 2 regens. When I did this though, I changed all my settings to what you suggested and just changed the 16 - 40 for the draw time. I hope that was correct! I'll keep you updated on how the water feels.

That should be fine so long as there was 3 hours from brine fill to start of regeneration for each of the two regeneration cycles.

[Gary Slusser]

Over the last 6.5 years I've used 2 hours and not had problems. A customer did salometer tests before and during regenerations for months with both Pre and POST brine refill at 2 hours and couldn't find a problem.

Other dealers call for 4 hours minimum.

BTW Batboy, I wouldn't program it the way Bob says. If you look at 15% of 40K, you probably won't get 8 days between regenerations and there is no need for that reserve. But try it and see how it goes.

[batboy]

Well Gary, more knowledge is always better. How would you suggest to program this?

[Gary Slusser]

Take the 15% off the 40K and see what numbers you come up with and how many days between regenerations.
Plus you are using 75 gals/day/person and I would use 60. I don't agree with 5 gpg for each ppm of iron, use 4. I also don't agree with the number of minutes for the cycle positions.

[batboy]

Take the 15% off the 40K and see what numbers you come up with and how many days between regenerations.
Plus you are using 75 gals/day/person and I would use 60. I don't agree with 5 gpg for each ppm of iron, use 4. I also don't agree with the number of minutes for the cycle positions.

What settings would you recommend using?

[TWEAK]

I had some of the guys help me with programming my 7000SXT a few months ago.

The experts here will give good advice but I do have one suggestion. Gary Slusser recommended to me that I use the DFF (downflow-fill first) mode rather than the default DF mode. DF refills the brine tank after the regen, letting is set until the next regen. DFF refills the brine tank at the start of the regen, and allows time for the salt to dissolve before getting on with the regen. Gary claimed that DFF helped keep the brine tank cleaner and reduced the chances of salt bridging. There was some debate about this -- others felt that there was no effect on salt bridging or brine tank cleanliness.

I tried both modes and my experience supports Gary's choice of DFF in terms of salt bridging. I haven't been able to confirm the cleanliness argument, but here during warm weather I have definitely seen salt bridging in the DF mode. I believe that what is happening is that, in DF mode, some of the water evaporates during the week between regeneration. The brine is a saturated solution, so when you lose water salt precipitates out. This salt ends up causing the bridge. It's easy to break up but annoying. On the other hand, if you use DFF as Gary suggested, the brine isn't sitting around all week - only a couple of hours. It therefore doesn't evaporate away any water and so no salt precipitates out to form a bridge. I'm not 100% sure that this is the mechanism but it makes sense... and since changing to DFF, I see no salt bridging no matter the weather.

I also want to comment on the calculation. We seem to use 60 gal per person per day. I think this is a good number when you have at least a few people in the household. But in my case I am down to just one person (me) and the water consumption is definitely higher than one person. The reason is that with one person, your water use (no matter how hard you try) just isn't as efficient. Every shower and most of the sink uses start with dead cold water in the pipes, causing you to run the water a bit. And despite your best effort you end up running more partial laundry loads and even are more likely to run more partial dishwater loads. So I would recommend using the 60 gal figure for starters, but keep an eye on it and be open to jacking up that per-person figure if there are less people. I use 85 gallons with one person and while that may sound high, it's the right number for me... and I'm NOT an extravagant water user!

[Gary Slusser]

I think bridging happens with post refill due to the water being wicked up into the salt above the water line. With a tight salt tank lid there can't be much if any evaporation of water because there is no air flow through the tank. I think the dry salt sucks up the humidity.

[TWEAK]

Interesting thought, Gary. Seems like if the culprit was water wicking, it would be just as likely to happen in two hours of a pre-fill cycle as it would in a week using post refill, no?

I agree you don't get a lot of evaporation with the lid on the tank. But you're bound to get some evaporation. Those salt tank lids are not all that good. It would be fairly easy to the actual amount of loss over a week... sounds like a good science project!

Hey here's another question for you all. I'm using about 1/4 of my softener's capacity, with the salt dose adjusted down due to the decreased usage. Is it a good idea to run a full regen with 20+ pounds of salt every so often or would this be a waste?

[Akpsdvan]

Why again are you running at 25% of what the system can do?

[TWEAK]

Why again are you running at 25% of what the system can do?

I bought the system sized for more people living here. One kid got married, one went off to live at school, one got a job out of the area.... Now it's just me.