tannis filter issues with higher pressure

[Alexdc99]

I had to replace my pressure switch so I installed a 30/50, the old one was a 20/40 and I also up'd the pressure tank to 28. My problem is when I run a bath it seems as though I am putting the water through my tannis filter to fast and it not removing the stain. When I use any other tap whether it the kitchen sink or bathroom sink, dish washer or any other under 2.5gl a minute draw everything is fine. Is it possible to put the water through faster than it can get cleaned? My tannis filter is a older Culligan mark 88 rebuilt 3 years ago to be a tannis filter using potassium chloride for the re-gen. Oh, I have a chlorine injection unit with turbitity filter before the tannis filter.

Thanks

[Bob NH]

What is tannis? What is a tannis filter? I can't find anything about it and can't find tannis in the dictionary.

[plumber1]

Do you mean tannen?

[Alexdc99]

I meant tannins, my water is stained and I use ion exchange to remove it.

From the culligan web site

Yellowish cast to water after softening and/or filtering.

Tannins (humic acids) in water from peaty soil and decaying vegetation. Various effects.

1. Adsorption via special macro-porous Type I anion exchange resin regenerated with salt (NaCl) up to 3.0 ppm.

[hj]

If you are opening the tub faucet all the way, then the added pressure will create a faster flow, although we do not know if the tannin filter has a gpm limitation. I would think it was large enough to absorb any increase in flow with out affecting the quality of the ouput water. The other fixtures may be flow limited so the pressure would have no effect on them.

[Alexdc99]

All the other fixtures are 2.5gl or less a minute. In my manual is says that the tannins filter has a limit of 7.5gl/min with 15psi drop in pressure. It could be possible I am right around the limit and the filter can't clean it at that limit anymore. My WX-202 Well-X-Trol has a draw down of 6.8gl at 30/50psi so I think something isn't right with my filter. I have 3/4 inch pipe through the filters and right to the hot water tank, 1/2 cold line are tapped off the 3/4 so I can move a lot of water when both taps are running. I'll give Culligan a call to see what they say.

[Gary Slusser]

All softeners, backwashed or regenerated filters have a SFR (service flow rate); maximum gpm that if exceeded prevents the softener or filter from removing all of what they are supposed to. The hardness etc, that gets through the softener or filter is called leakage.

The SFR has to be equal to or higher than the peak demand flow rate gpm. The peak demand flow rate is the TOTAL water run through the softener or filter PER MINUTE.

Increasing water pressure increases the gpm flow rate. A good possibility is that the higher pressure has caused some tannin resin to be backwashed out of the tank OR... they don't have the correct DLFC (drain line flow control) in the unit and the time of backwash set correctly and the resin is not fully regenerated; hence it can't remove all of the tannin in the water now.

The use of potassium chloride instead of sodium chloride, regular softener salt, is another cause of insufficient regeneration. Softener and 'filter' resins are not in the potassium form, they are sodium form, so you must use a higher salt dose to use potassium chloride (salt substitute).

Since the filter worked before, a solution to your problem is to set the tank and pressure switch for 20/40 psi (19-18 psi air precharge when the tank is empty of water). That assumes there is a top basket in the 'filter' and you didn't backwash tannin resin out of the tank.

Another solution is a correctly sized softener/filter for your peak demand. You have what is called a top dressed softener; tannin specific (anion) resin on top of (cation) softener resin.

[Alexdc99]

Ok that gives me something to try, I'll set it back down to 20/40 and see if everything goes back to normal.

On the top of the control unit there is a metal plate with three screws and under it a a nozzle with a metal screen on the top, is that what you mean by "top basket in the 'filter' ".


Right now my salt dose is set to 15lbs, how do I go about figuring out the added lbs I will need to increase it by?

Thanks for the help.

BTW, I checked at the bottom of my sump pit and I have no signs of any resin being washed out of the unit. Also on a side note, the 3/4 inch pipe replaced the 1/2 that orignally leaked, could switching back to a 1/2 pipe from the softener to the water heater and running everything back on 1/2 copper slow the gpl going through the softener but keep the 30/50 pressure?

[Gary Slusser]

The metal plate is over the injector and injector screen, this is not a top basket.

A top basket is inside the resin tank. Some Culligan tanks have separate inlet and outlet nipple fittings with dove tail connections to the control valve that are 3/4" and the inlet has a plastic piece inside the nipple instead of a top basket. I call the the plastic piece a diffuser. I somewhat doubt they are using that type tank, and if not, then the tank will have a 2.5" hole in the top that the control valve screws into or is clamped to the tank. The top basket is on the distributor tube.

I certainly wouldn't change the size of pipe back to 1/2". And there's no way for you to know how much tannin resin is supposed to be in the tank, and the tank should not be filled because there has to be an empty space above the resin for backwash expansion of the bed. So I strongly suggest you call Culligan for service.

Since you don't see any resin in the sump pump hole, unless it got out of there, you probably didn't lose resin, so there is something else wrong.

[Alexdc99]

On a side note, it took my 41 seconds to fill a 5 gallon container last night, so I am very close to the limit of 7.5 gallons a minute. I have a call in to Culligan, just waiting for a call back.

Anyone know how to figure out the gallon per minute difference with a 3/4 pipe using 40psi or 50psi pressure.

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Update: Just talked with Culligan and they said it could take a few backwashes to get the unit back to operating fine, with air getting in the system and what-not is may take a bit of time. Does this sound right? It's only been 2 days and 1 recharge, maybe I should do another one. The systems I have they said could operate fine with 30/50 pressure.

[Alexdc99]

Found my problem. I am getting chlorine passing through at higher water volume, over 3gl a minute. Took a week to find a pool company that stocks chlorine test drips in the winter.