Flooded Salt Tank in Kenmore H2O Softener

[whitedavidp]

Hello. I purchased a new-ish home (1 year after it was built) that has a model 625.388170 (or maybe 625.388180 - same manual for both) H2O softener. Until today, I had every reason to believe that all was fine with this unit. I generally do not let the salt level get very far down before refilling and I keep it near maximum.

But I have been a bit lazy about adding salt recently so I checked today and found that it was down much further than I usually allow it to get - 5 out of 8 max on the level markings. While looking, I noticed that there was water in the salt tank. I know that there is supposed to be water in the tank but the online info at WATER TREATMENT FAQs, FREQUENTLY ASKED QUESTIONS ABOUT SOFTENING AND CONDITIONING where at the bottom it says this should be only 2-5 inches high. Today, the water was just at or slightly below the level of the salt. For reference, this would be at least 2 feet above the bottom of the tank.

I thought this odd (or at least unexpected) so I did a bit of research here KENMORE WATER SOFTENER FILTER ANIMATIONS, TROUBLESHOOTING and found that this seems a known situation. I followed the instructions to clean the venturi assembly. This was easy to do and I found nothing that was unexpected - all seemed fine. The last step in this process is to manually trigger a recharge. I did this and it took quite a long time to complete. During this process, the water level in the salt tank went down and out of sight. I cannot say how far down exactly but much lower than it was when I started all this.

At the end of the recharge cycle a rinse occurs and water starts to run. When this happened I watched what was going on and I noted that water was running into the salt tank at this point through the overflow tube/hole. This seemed to cause the water level to fill up to about the point where it was originally.

This seemed odd and I looked to see how it was plumbed. The overflow hose comes out of the overflow hole and tee's into the main drain line for the unit. This then connects to the pressure bleed line from the water heater located right next to the softener. The combined drain line goes through a hole in the side of the house and out to a hose which drains on the ground. I checked this during the rinse and did see water coming out ok. I saw not signs of blockage or restriction.

The diagrams in the manual all show the drain and overflow lines going their separate ways to the drain. They are not shown interconnected like they are on my unit. So I am guessing that when the rinsing occurs, the waste water is finding it much easier to flow back into the salt tank via the overflow tube than it is to go all the way out of the house to the drain and this is what is causing the higher than expected water level.

Nothing has been changed here so I am guessing that things have been this way since installation and I just never noticed due to the high salt level in the tank. So my questions:

1. Is this a satisfactory situation? Or does this lead to inefficiencies in the system? Could this lead to an overflow situation which could cause the floor to get wet?
2. If this is not a satisfactory situation, what is the best action to take? There is no floor drain and I would like to keep the single hole and drain out the wall, if possible.

Thanks for your time and comments.

Added 11/23 @ 9am

I just added two photos to try and clarify the situation. The first shows how the drain and overflow lines from the softener are tee'ed into a single line. I found the install manual and it specifically says NOT to combine these lines. The second photo shows how the combined line from the softener is added to the water heater blow-off line which then exits the house through the wall to simply drain on the ground.

[HayZee518]

Both lines are draining through a common hose. the normal overflow hose is open to atmosphere through the wall hole and outside hose. In the high pressure bleed line I would say install a horizontal check valve with the arrow pointing downstream [outside] not towards the tank. when the overflow starts the check valve won't allow water to enter the system but when it needs to vent it will open. to be double sure install another one in the overflow hose [pipe] that way water either or won't flow back into the other. if the pressure draining in one line at the same time the other one is open, the higher pressure line will close the other check valve and will drain through your common pipe.

[Gary Slusser]

I just added two photos to try and clarify the situation. The first shows how the drain and overflow lines from the softener are tee'ed into a single line.

I found the install manual and it specifically says NOT to combine these lines. The second photo shows how the combined line from the softener is added to the water heater blow-off line which then exits the house through the wall to simply drain on the ground.

Separate them, it's surprising you haven't noticed this problem in the past but understandable when you've been keeping so much salt in the salt tank.

DO NOT add check valves, they require pressure to open and cause a restriction in the drain water flow from the control valve which is already flow controlled in the control valve based on the volume and type of resin in the softener (to a tenth of a gallon) and more restriction will cause incomplete backwashing of the resin bed and failure of the softener.

Separate the two lines and only keep the salt tank about a 1/3rd to half full. I also suggest that IF your T/P valve of the water heater blows off excess pressure or because of high temp, you may get that hot water back into the salt tank and control valve. That will exceed the max temp of the plastics of the softener and could cause a huge failure of your resin tank and control valve allowing flooding of the area where the softener is installed, but at least the distributor tube to weaken which can allow resin out of the softener into your plumbing to your fixtures and appliances.

So, I would get the drain line off the water heater T/P line.

This is the only way to do it all right. Also, IF the green drain line is kinked shut or partially shut where it lays on the part of the bypass valve, that restricts flow and will cause too much water in the salt tank, so get it up where it can't close due to its weight.

[HayZee518]

swing check valves DO NOT require pressure - they are closed by gravity and back pressure.

[whitedavidp]

DO NOT add check valves, they require pressure to open and cause a restriction in the drain water flow from the control valve which is already flow controlled in the control valve based on the volume and type of resin in the softener (to a tenth of a gallon) and more restriction will cause incomplete backwashing of the resin bed and failure of the softener.

Thanks for the response Gary. If I were to add a check valve, it would be to the salt tank overflow drain line rather than the resin drain line. After all, the backflow is coming into the salt tank from the resin tank drain line due to the higher pressures during the brining rinse cycles.

I am inclined to agree with another poster that a high quality swing type check valve, if properly mounted, requires no force to allow flow to pass in the intended direction. It could even be mounted in such a way that gravity actually holds the swing valve open a slight amount as its default state. Backflow with enough force would still shut the valve and prevent leaking into the salt tank.

The above said, installation of a check valve is clearly not the ideal choice. If a salt tank overflow were occur during a time when the high pressure output was flowing, the salt tank overflow drain would be rendered useless. However, it appears that the only time water is legitimately flowing into the salt tank (and hence, likely to cause an overflow condition) is during the first phase of the recharge cycle. That phase must complete before the later phases which produce high pressure (and thereby shutting the check valve) can begin.

[HayZee518]

the matter of using check valves is just one suggestion. it isn't a cut n dry condition. by rights two seperate drain lines should have been used but unfortunately weren't.

[Redwood]

So why not run a second drain line rather than "Rig" the thing?

I mean just because this is a handy man type forum and not a pro forum is that a reason to rig everything in sight?

[Gary Slusser]

swing check valves DO NOT require pressure - they are closed by gravity and back pressure.

Yes I know. And his flow out of the salt tank is non pressure/gravity flow/downhill only, so a swing check is not a good choice.

I also know that I have seen and heard of more than a few salt tanks that have overflowed, it is my business.

I've also found a few water heater T/P valves allowing water to flow constantly, and drain water flowing constantly because the control is stuck in a backwash or rinse position of a regeneration and maybe 2 thousand softeners putting water into the salt tank when they shouldn't. Guess what hot water does to PE drain line tubing with a 70 psi rating @ 73*f.

Excess water in a salt tank is the most common failure of a softener; all softeners are prone to have the problem.

The water can flow into the salt tank at any time and in any position the control valve is in during a regeneration, including brine draw or while in the Service position.

And now we see the OP talking about installing the swing check valve so it is partially open instead of paying attention to the rest of what I said about the T/P line etc. etc. and his assumption that the water is only going into his salt tank because of the drain water flow backing up into the salt tank. He may be wrong but if he is correct, how does any type check valve anywhere find and cure the cause of that?

He is doing his damnedest to not have to change things, and if he doesn't, he runs a fairly high risk that he is going to have a salt water flooded floor. Actually he dodged a bullet right now or none of us would be discussing this. Depending on its size, his softener will run from 30 gallons up to 150 gallons to drain during a regeneration. And he probably didn't find this problem as it happened, it may have been days before he found it, and it was luck that he went to check the salt level then or it could have been many days longer. And, this cost him many lbs of salt.

Cleaning that much salt water up, especially on a cement floor, is a difficult thing to do because the salt penetrates the cement and the floor will never be the same afterward. BTW, 99.9% of this post is directed at him, so no hard feelings.

[Gary Slusser]

However, it appears that the only time water is legitimately flowing into the salt tank (and hence, likely to cause an overflow condition) is during the first phase of the recharge cycle. That phase must complete before the later phases which produce high pressure (and thereby shutting the check valve) can begin.

This water isn't flowing "legitimately"; this should have never been allowed to happen because the tank overflow is never supposed to be teed into the drain line, or the drain line teed into the tank drain line.

"That phase must complete before the later phases" nope, it doesn't work that way, and does only partially IF you have a float controlled safety brine system in the salt tank. And then, even if the float isn't a safety and it is used to control the salt dose setting, IF the brine refill flow is stopped by a float controlled valve, the resin tank control valve stills goes into backwash and rinse etc. to finish the regeneration.

Undo the Tee to the salt tank drain line, do not use the water heater drain line unless you find out why it can't take the flow from the softener and cure the problem or, gamble a flooded floor at some point in the future. You can buy a 100' roll of PE drain line for like $60+/- at any online or local water treatment dealer.