If your water softener has stopped doing its job, you may have worn or clogged parts in the control head that need repair or a complete rebuild. Here's the fix.
By the DIY experts of The Family Handyman Magazine
You might also like: TBD
$20 – $100
Water softener problems
Before we jump into rebuilding your existing water softener, you should ask yourself whether it’s worth putting money into an older unit. Older units waste salt and water: They use a daily timer and recharge after a set number of days whether the resin is depleted or not. Newer models recharge only when absolutely necessary, so they can save quite a bit over their life span.
When a water softener fails, the symptoms are hard water, frequent regeneration cycles and excessive salt usage, brine tank overflow or resin beads clogging your faucet aerators.
Most softener problems are caused by worn or clogged parts in the control head or a salt bridge in the brine tank. We’ll explain how to check for brine tank issues and show you how to completely rebuild the popular Autotrol control head, which is installed on about half of all water softeners sold by water professionals. So if your water softener looks like this one, read on. However, if you have an older water softener and the rebuild doesn’t fix the problem, you won’t have wasted your time because you may have to replace the resin bed as well. See Replace a Water Softener Resin Bed to find that fix.
You’ll need a T-50 “star” bit (sold at home centers or online) to remove the access covers, along with small flat-blade and Phillips screwdrivers, and needle-nose and regular pliers. The entire rebuild takes less than an hour.
Start with a salt bridge and motor test
It doesn’t make sense to rebuild a control head if the problem is just a bad motor or a salt bridge in the brine tank. So check those first. Jam a broom handle into the salt tank. If it hits a hard obstruction before reaching the bottom (or the salt shelf), you probably have a salt bridge. If so, scoop out the loose salt, and then break up the solidified salt by plunging a broom handle through the bridge, and refill the brine tank with salt.
Next, put the softener into manual regeneration mode and check for water flow at the floor drain. If water flows into the drain, that confirms the motor is working. However, if there’s no flow, check the camshaft to see if it’s engaged with the motor. If it is, check for power at the motor with a voltmeter. If the motor has power but doesn’t turn the camshaft, replace the motor. Once the motor is replaced, continue testing.
Figure A: Water Softener Control Head
Autotrol control heads like this are used in about half of all water softener installations.
For a large, printable diagram, see “Additional Information,” below.
Identify your model and get the parts
Control head manufacturers never list their brand name or model number on their products, so you’ll have to decipher that information by appearance. Softenerparts.com shows photos of all the most common brands and models. That’s how we identified this Autotrol No. 255 unit.
If you’re willing to disassemble the unit and check the condition of each part, you can save some money by ordering just what you need. Rather than do the job twice, we opted for a complete rebuild kit for $84. To order the correct parts, you’ll also need the diameter of the resin tank.
Close the bypass and remove the top plate
Photo 1: Remove the camshaft
Unscrew the cam lock or rotate the cam lock lever and lift up on the rear end of the camshaft. Pull it out of the motor and set it aside.
Photo 2: Disengage the springs
Slide a small flat-blade screwdriver under the spring and pry the tab out of the valve disc. Then pop the spring up.
Photo 3: Remove top plate
Unscrew 12 retaining screws. Then lift the top plate straight up. Disengage the meter cable (if equipped) and set the plate on top of the bypass valves.
Turn the softener shutoff valves to the bypass position and start a manual regeneration to relieve internal pressure. Next, remove the camshaft (Photo 1) and disengage the valve disc springs (Photo 2). Then remove the retaining screws and the top plate (Photo 3).
Swap in the new parts
Photo 4: Install new water softener valve discs
Yank the old water softener valve discs straight up. Then insert the matching replacement discs (no lube needed). Press the rubber portion of each disc into the water softener valve body until it’s flush.
Photo 5: Replace the injector
Unscrew the injector cap with the T-50 star bit. Then grab the injector with needle-nose pliers and yank it out, noting its direction. Clean out any debris and push in the new injector so it faces into the control head. Reinstall the cap and tighten until snug.
Photo 6: Replace the brine refill check ball
Grab the brine refill control cap with pliers and unscrew. Smack the control head with the palm of your hand to knock out the rubber check ball. Clean any debris and install the new check ball. Reinstall the control cap.
Photo 7: Clean or replace the screen cap
Unscrew the screen cap and check its condition. Replace if the screen is damaged or permanently clogged.
Replace the worn valve discs with the new ones from the kit (Photo 4). Then remove the injector cap and injector (Photo 5). Replace the brine refill check ball (Photo 6). Next, remove and check the screen cap (Photo 7). Replace the drain control check ball following the same procedure as for the brine refill check ball. Unscrew the clear plastic dome and replace the air check ball.
Reassemble by lining up the top cover directly over the valve discs. Lower it and lift the springs out of the way. Install the top plate screws and pop the spring tabs into the holes in the valve discs. Reinstall the cam. Turn the bypass valves to the service position and perform a manual regeneration to purge air out of the control head. Then enjoy the soft water.