How to Fix a Water Softener: Symptoms and Error Codes
To fix a water softener, check bypass, salt and power first. Symptom-to-fix table and Fleck 5600SXT and Clack WS1 error codes from the manuals.
Most water softener problems come down to three checks before anything else: the bypass valve is in service, there is salt in the brine tank sitting above the water, and the control has power and the right time of day. Fleck’s and Clack’s service manuals both list those as the first causes of hard water. If all three are fine, match your symptom in the table below to its likely cause. The fixes here come from the Fleck 5600SXT and Clack WS1 manuals.
Symptom, cause and fix
| Symptom | Likely causes | Fix | Manual reference |
|---|---|---|---|
| Hard water | Bypass open; no salt; injector screen plugged; brine refill too low; distributor tube leak; internal seal leak | Close bypass; add salt; clean injector screen and brine line flow control; replace seals | Fleck “Hard water”; Clack problem 8 |
| Hard water, salt level unchanged for weeks | Salt bridge or mush (no brine forming) | Break the crust; if it won’t break, drain and replace the salt | EcoWater; Fleck “maintain salt above water level” |
| Won’t regenerate | Power interrupted; switched outlet; timer or board fault; meter not counting | Use a constant, unswitched outlet; reset clock; check meter cable | Fleck “fails to regenerate”; Clack problems 6–7 |
| Regenerates at wrong time | Power outage reset the clock; regen time set wrong | Reset time of day and regen time | Clack problem 4; Fleck (8-hour power loss) |
| Brine tank full of water | Plugged drain line flow control; plugged injector; debris in brine valve or brine line flow control | Clean flow controls, injector and screen; replace brine valve seat | Fleck “Excessive water in brine tank”; Clack problem 11 |
| Doesn’t draw brine | Plugged injector or screen; drain line restricted, too long or too high; water pressure too low | Clean injector; clear drain line; raise pressure to 20 psi (Fleck) or 25 psi (Clack) | Fleck “fails to draw brine”; Clack problem 12 |
| Salty water | Low pressure; wrong injector; restricted drain line; rinse cut short | See the salty water guide | Clack problem 10 |
| Uses too much salt | Salt or refill setting too high; frequent regeneration from leaking fixtures | Correct salt setting; fix leaks | Fleck “used too much salt”; Clack problem 9 |
| Iron in softened water | Fouled resin bed | Increase regeneration frequency and backwash time; clean resin | Fleck “Iron in conditioned water” |
| Pressure loss | Iron buildup in the inlet line or softener; debris after plumbing work | Clean line and control; add resin cleaner | Fleck “Loss of water pressure” |
| Resin beads in plumbing or drain | Air in water system; wrong drain line flow control | Check well air eliminator and for a dry well; check drain rate | Fleck “Loss of mineral through drain line” |
| Water running to drain constantly | Power outage mid-regeneration; damaged seals or piston; foreign material | Let control finish; replace seal stack or piston | Clack problem 13; Fleck “Drain flows continuously” |
Hard water returning
Start at the valve. A bypass handle left in bypass after maintenance is the first cause in both manuals. Next, look in the brine tank: Fleck says to keep the salt level above the water level, and Clack lists no regenerant or a low level as a cause. If both are fine, the softener may be out-running its capacity. Clack lists high water use, a meter that isn’t registering, and changed water quality, and says to test the water and adjust the program. A capacity that no longer fits the house is a sizing problem; see the water softener size calculator.
Salt bridges and salt mush
A salt bridge is a hard crust that forms in the brine tank and leaves an empty gap between the salt and the water below, so no brine forms. EcoWater says humidity, temperature changes and the wrong salt cause it, and the test is to push down on the salt with a broom handle. If it gives way, break up the crust.
Salt mushing is worse: dissolved salt recrystallizes as sludge at the bottom of the tank. If pushing doesn’t break it, EcoWater’s fix is to drain the brine tank, dig out the old salt, and refill with fresh salt. To prevent both, Fleck says not to use granulated or rock salt, and Pentair’s user guide recommends clean, impurity-free salt such as pellets and says not to use ice-melt, block or rock salt.
Iron fouling the resin
Well water with iron coats the resin. NDSU Extension says softeners can remove up to 10 ppm of iron and manganese, that excess iron or hydrogen sulfide can reduce softener effectiveness, and that water above 10 ppm may need a dedicated iron removal system. Fleck’s fix for iron in softened water is to increase regeneration frequency and backwash time. EcoWater recommends a resin cleaner poured down the brine well, followed by a manual regeneration. If iron keeps coming back, treat it ahead of the softener; see iron in well water.
Not regenerating: clock, power and settings
Both manufacturers want an uninterrupted outlet. Fleck says power interruptions longer than 8 hours can make the controller lose its time setting. Clack lists an outlet controlled by a light switch as a cause of a blank display. A flashing time of day on either valve means the power went out; reset the clock, then check that the regeneration time and capacity settings survived. If a manual regeneration works but automatic doesn’t, Clack points to the meter (bypass, unplugged cable, stalled turbine) or to programming.
Brine tank full of water
Standing water above the normal level means brine is going in but not being drawn out. Fleck’s causes are a plugged drain line flow control, a plugged injector system, a timer not cycling, and foreign material in the brine valve or brine line flow control. Clack adds damaged seals, a kinked drain line, a plugged backwash flow controller and a missing refill flow controller. The injector, a small venturi in the valve body that pulls brine from the tank, appears in both manuals’ lists. Fleck’s manual says the system must be depressurized before any connection is removed, so put the softener in bypass and relieve pressure first.
Salty water
Salty-tasting water usually means brine wasn’t fully rinsed out during regeneration. Clack’s causes for residual regenerant in service water are low water pressure (it must stay at 25 psi or more), the wrong injector size, and a restricted drain line. The full set of causes, and how much sodium is normal, is in why softened water tastes salty.
Error codes
| Valve | Code | Meaning | First step from the manual |
|---|---|---|---|
| Fleck 5600SXT | 0 | Cam sense: drive took longer than 6 minutes to reach the next position | Unplug; check cam switches, motor and drive train; plug back in |
| Fleck 5600SXT | 1 | Cycle step: unexpected cycle input | Unplug; check cam switches and valve/system type settings |
| Fleck 5600SXT | 2 | Regen failure: no regeneration for over 99 days (7 days on day-of-week setting) | Run a manual regeneration; check meter and settings |
| Fleck 5600SXT | 3 | Memory error | Master reset and reprogram |
| Fleck 5600SXT | UD | Upper drive sync after power failure or programming change | Recovers automatically |
| Clack WS1 | 1001 | Control unable to sense motor movement | Check motor seating and wires, board seating, reduction gears |
| Clack WS1 | 1002 | Motor ran too short and stalled looking for next cycle position | Check for foreign material, binding, tight drive gear, voltage |
| Clack WS1 | 1003 | Motor ran too long looking for next cycle position | Check motor, piston and seal stack, drive bracket |
| Clack WS1 | 1004 | Motor ran too long and timed out reaching home position | Snap drive bracket in properly |
| Clack WS1 | 116 / 117 | Alternator or bypass (MAV/NHBP) valve motor ran too long / too short | Check MAV wiring, engagement and programming |
After a Clack fix, the manual’s resync step is to press NEXT and REGEN together for 3 seconds, or disconnect power to the board for 5 seconds. Fleck’s user guide says to unplug and replug for codes 0 and 1 and to call technical support if an error continues.
Repair or replace?
Most fixes above are parts: an injector, flow controls, a seal and spacer kit, a piston, a meter or a power adapter. Both manuals treat those as replaceable. Clack’s last cause for hard water is a fouled media bed, fixed by replacing the media. Replacement of the whole unit makes sense when the tank or valve body is cracked, or when the softener is simply too small for the house and its hardness. If you are shopping, start with the water softener guide and our water softeners for well water picks.
Other troubleshooting
Softener pressure problems sometimes start at the well. If the whole house has low or no pressure, including on bypass, see well pump not working.
Sources
- Pentair — Fleck 5600SXT Downflow Service Manual (42684 Rev L)
Troubleshooting table, error codes 0–3 and UD, 20 psi minimum pressure, 8-hour power loss, salt type, 125 psi and 110°F limits - Pentair — Fleck 5600 SXT User Guide (MKT-UG-013 Rev G, March 2026)
Error code list, salt guidance, call support if water tastes salty or salt is not used - Clack Corporation — WS1 and WS1.25 Drawings and Service Manual (V3115-99)
Troubleshooting problems 1–13, errors 1001–1004 and 116/117, resync procedure, 25 psi minimum - NDSU Extension — Water Softening (Ion Exchange), WQ1031 (rev. May 2022)
Softeners can remove up to 10 ppm iron and manganese; iron and hydrogen sulfide reduce effectiveness; brine tank cleaning - EcoWater — Water Softener Maintenance Made Easy
Salt bridge and salt mushing descriptions and fixes; resin cleaner use