Fixing a Sears Kenmore Water Softener

I have been struggling with the Water Softener for a few months now. I got it fixed by Sears for about 165$Cdn two years or so ago. A few months ago, it started having problems again. So I decided to try and fix it myself.

What is a water softener?

First a little background.

In North America city water is locally produced from underground water, not from a river like in Egypt. Deep under the ground there are aquifers, and the city taps into it, treats it and make it available to the inhabitants. If the bedrock has a lot of calcium, .e.g limestone, in it, then the water is often said to be "hard water".

Hard water causes a lot of problems: dishes would look cloudy, the tea kettle will have white residue in it, soap will not rinse from your hand (no squeaky clean feeling), your hair will clump if you use soap in the shower instead of shampoo, and the water heater efficiency will decrease as the calcium from the hot water precipitates on its walls. Soap and detergent use is also increased.

How does a water softener work?

So, there is a market for water softeners in places that have hard water.

A water softener works by having a tank that is filled with salt, and a tanks full of a special resin. The resin can remove the hardness from the water, but requires that it be regenerated by washing it with salt brine during regeneration. Water softener are either demand based (after a certain number of gallons have been processed), or time based (e.g. twice week). Regeneration happens in the early hours of the morning, depending on how you set it. It goes through several cycles, which are basically:

  • Fill: Water is passed to the salt tank
  • Brining: Water is left in the tank to form brine
  • Rinse: The brine is used to rinse the resin, remove the calcium that it has removed in the past, and make it able to remove calcium again
  • Back Wash: The resin tank is flushed for residues and iron deposit
  • Fast Rinse: The resin is rinsed from all the above
  • Service: This means that the water softener is serving soft water for the house

There are many brands of water softeners out there in the market. Many are rebranded. For example, Sears Kenmore, Ecoline and General Electric (GE) are the same. Culligan is also similar.

About my handyman's skills

Before I start, I should say that I am not at all handy with maintaining a house. Part of it is due to the fact that in Egypt most people live in concrete apartments, and not woodframe and drywall houses with lawns. Part of it is that I never got the hang of being mechanically adept, whether it is plumbing, carpentry, car maintenance, and such. So, fixing a water softener, which involves mechanical, electrical and plumbing aspects is quite a challenge.


Many things can go wrong with a water softener. The basic complaint is that "there is no soft water". Another is high water level in the salt tank. Yet another is salt level that does not go down as the weeks pass.


The manual for a water softener often has some comprehensive diagnostics that can be done to see

Start with cleaning the nozzle and Venturi. This should not require any tools, and can be disassembled and assembled by hand. Take note on how things fit before you remove them. Wash the components in water. Use some vinegar. Make sure there is no deposits, salt, rust, calcium or debris.

Then check the float in the salt well in the tank. The float should be able to move up and down, and the hose should be able to inject water in the tank and suck it again.

Then shut the water supply, drain the house (open the lowest lying faucet in the house), then disassemble the cam gear and rotor from the valve head. Check all the seals and gaskets and that there is no wear on the smooth side of the rotor.

Run the diagnostics as per the manual, and make sure that the cam gear moves well. If the motor is skipping and making a clicking sound and failing to move the cam gear, then replace it.

Replacing all the gaskets, the rotor, the cam gear and the motor should solve most problems, and only cost me 74$ Cdn. That is provided that the nozzle/venturi are clean, and that there is no obstruction to the float assembly.

Check for the formation of a salt bridge, specially in humid environment. Tap the side of the tank and see if there is a hollow sound at some spot under a solid sound. Use a broom stick to break it.

Once every six months, get a water softener cleaner (basically a sulphite powder that removes iron deposit. You can buy it at Canadian Tire or other hardware stores. It is more expensive at Sears, so avoid buying it there.

Every year or 18 months, try to remove all the salt from the tank and wash it. You can use warm water, and a wet/dry vacuum to remove it.


Fixing a water softener is easier than you think. Save your money and do it yourself. Get the manuals online, go buy the parts, and do it.

The morale of the story is: If I could do it, anyone can do it.

Resources and Links

Here are some useful links with more information:




One hour to an hour and fifteen minutes is about normal.

kenmore water softener model # 6253484500

Help! We need a transformer for the water softener part # 7095373, 24 volt-10VA. Sears claims they no longer sell the part. Do you have any suggestions other than buying a new softener?

Thanks for your help,

Brenda McCAllum

Replacement transformer

Try Part# 7275907 - it is a certified replacement to the part number you listed.

Small water flow when softener not recharging

I have a Kenmore UltraSoft 400 and I noticed there is a constant trickle coming out of the discharge hose when it is not going through its recharge.
Why would this be?

Kenmore Ultra Soft 400 Model: 625.388450 Transformer


Looking for the transformer for my water softner.
Was told by the serviceman that these rarely go bad. Guess what? Mine did. Of course going to Sears service center and calling the repair line did no good. Anyone know where I can get one?
This is what is says on the back.

AC/AC Adaptor
Class 2 Power Supply
Model#: LF24400A-41
Part#: 7095373
Input: 120V AC 60Hz
Output: 24V AC 400mA
Per the serviceman I was told it was 10milliamps

Thanks for you help on this.

My transformer bad too

Ultrasoft 180 with a bad transformer too. Maybe not so uncommon?

DON'T BUY A SEARS Water Softener with the plastic valving

This has got to be the lameist design ever conceived. The brine tank fills with water because the connection leaks and you can't see it unless you remove the top cover or shroud that covers the mechanism on top of the unit. The top is designed to drain any leaks from this valving into the brine tank. If you are unlucky it will also find it's way down the back of the tank and create what appears to be a tank leak. If you don't have a drain tube hooked to the over flow then that will also leak onto the surface it is setting on. The plastic plumbing relies on two "O" rings and two plastic clips to make the seal. The "O"rings ware over time (for some unknown reason) and begin to allow the leak. In order to remove the plastic clips and replace the "O" rings you need to bypass the system and relieve pressure in the tank by setting it to re-charge and when pressure is releaved, unplug the power from the wall and proceed with replacement. I have had the unit for almost 4 years and this leak has occured twice now and I believe it is beyond repair by simply replacing the "O" rings. The unit preforms great when it's not leaking. So SEARS get rid of the cheap plastic and go to metal and these units will surve your customers for much longer. I plan on replacing the unit but not with a SEARS model.

I'm struggling with the same

I'm struggling with the same issue now. I've tried applying teflon tape under the O-ring which reduced the leak but i still have a drip every few seconds. I may try to get a slightly over-sized o-ring or apply some sort of safe RTV. Unfortunately, i broke the clips before realizing the pressure had to be relieved first.

How to fix a leak from bypass valve and OUT of main valve.

I fixed a leak that originates from where the bypass valve and OUT of the main valve connects. I found about the leak when it was time to add salt, the water level was up to just under the drain hose. So I replaced the bypass valve (7129871), new clips (WS60X10004), the bottom part of the valve body (7082053) and a seal kit (WS35X10005). I ordered all the parts from It's about $130, not cheap, but better than a new water softener. My water softener was 7yr old, so if this fix can last me another 6-7yrs I will be satisfied.