Field manual · Water Softener

Fleck 5800SXT (and 5800 XTR) softener control valve: quick sheet

Covers: Pentair Fleck 5800 valve body with SXT controller (also offered with XTR/XTRi controllers). Common on aftermarket and dealer-built softeners as the higher-flow step up from the 5600SXT.

Single sourceBrands: Fleck (Pentair)4 components

Downflow/upflow-capable residential and light-commercial valve with a reinforced PPO body, 3/4, 1 or 1-1/4 in connections and a 1.05 in OD distributor (riser) tube. Higher flow than the 5600: about 21 gpm continuous at 15 psi (1 bar) drop. SXT controller programming, error codes and cycle steps follow the same SXT family logic as the 5600SXT; see quicksheet-fleck-5600sxt-valve and the Fleck code entries.

Safety first

  • Bypass and depressurize before opening the valve.
  • Unplug the transformer before working near the board.

How it works

A motor-driven piston moves through the cycle steps (backwash, brine draw/slow rinse, rapid rinse, brine refill, service) set in the SXT program.

Brine is drawn by the injector (external-style fitting on the 5800); a plugged injector is the main cause of no brine draw (see water-softener-injector-venturi-clean).

Meter-initiated SXT valves count gallons through the turbine meter and regenerate on demand.

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Official manufacturer documentation

Always confirm values against the tech sheet for the exact model.

OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work. © 2026 OnCall Tech. Original content; not a reproduction of any manufacturer document.Generic part photos (not of this brand): Water softener resin tank with its control valve next to a storage tank by రవిచంద్ర (Ravichandra), CC BY-SA 4.0

Diagnostic guides for this appliance

Guide · Water Softener

Water softener and under-sink RO annual service: salt, brine tank, resin, filters and tank charge

A softener needs a monthly salt check (WQA: refill when under half full), periodic brine tank cleaning, breaking any salt bridge and, on iron or bacteria-prone water, a resin cleaner used per the manufacturer. An RO system needs pre-filter changes roughly every 6-12 months, the membrane every few years depending on feed water, a yearly sanitize at filter change and a tank air charge check with the tank empty. Intervals vary by maker; the model manual wins.

7 steps ~60 minmoderate
Guide · Water Softener

Water feels slippery or 'won't rinse off' after a softener install

A slick feel is the normal sign that hardness minerals are gone; soap rinses differently and people tend to use more of it in soft water. It is not a fault. Rule out real problems (salty taste, softener stuck in brine) and, if the customer dislikes the feel, adjust the blend or bypass setting on valves that have one, after a hardness test.

4 steps ~20 mineasy
Guide · Water Softener

Water softener noises during regeneration: normal vs fault

A regeneration cycle is noisy by design: the valve motor hums and clicks as it steps through positions, water rushes to the drain, and brine is drawn through the resin. That is normal as long as it ends when the cycle ends (typically a couple of hours). Noise that goes on for hours, runs outside regeneration, or sounds like grinding or banging points to a stuck valve, a clogged brine line, worn parts or a water pressure problem.

5 steps ~30 mineasy

Other water softeners & filters manuals

Manual · Water Softener

Fleck 9100SXT twin-tank alternating softener valve: quick sheet

Fleck 9100 valve with the SXT electronic timer on two resin tanks that take turns (alternating twin), 3/4 in. or 1 in. meter, sold since the 2000s under many dealer and online brands (e.g. Aqualux and Applied Membranes packages, 1.0 to 3.0 cu ft per tank). The older 9100 with a mechanical 3200 timer shares the valve body but not the electronics. Valve and serial label are on the valve/power head; the tank in service is shown both on the SXT display (U1/U2) and by a physical indicator on the valve. Search terms: Fleck 9100SXT, 9100 SXT twin, alternating softener, Fleck twin tank Err 0, 9100 tank in service, 9100SXT programming.

7 components8 common failuresFleck, Pentair
Manual · Water Softener

Kinetico non-electric twin-tank softeners (Premier Series, Premier XP, Signature Series): quick sheet

Kinetico water-powered twin-tank softeners: Premier Series softeners and the 4040s/4060s Overdrive combination units (carbon, Chloraban or Macrolite RX); older 2030s/2060s-era units follow the same non-electric principle but were not researched here, Premier XP (S150, S250, S250 OD, S350, S550, S650, S650 OD, Q850 XP and Q850 OD XP), and Signature Series 735 and 935. Sold and serviced through authorized local Kinetico dealers. Model and meter disc number are on the dealer's data sheet/owner's manual record page; the control valve with the regeneration indicator dot sits on top of the two resin tanks. Search terms: Kinetico not soft, Kinetico manual regeneration screwdriver, Kinetico running constantly, Kinetico brine tank full of water, Kinetico bypass yellow green red.

6 components7 common failuresKinetico
Manual · Water Softener

Culligan home softeners (HE / HE Twin with Aqua-Sensor or Soft-Minder, Medallist Series): quick sheet

Dealer-sold Culligan residential softeners: Culligan HE (High Efficiency) 1 in. softeners in 9, 10, 12 and 14 in. tanks, downflow and upflow, with Soft-Minder meter or Aqua-Sensor resin probe (owner's guides 2019-2021); HE Twin, HE Twin Upflow and outdoor versions; HE Municipal; and the Medallist Series 8 in. and Medallist Plus 30/45/60 (Accusoft four-key timer, 3/4 in. or 1 in. 5-cycle valve). Media tank serial number is on the top of the tank; control model/serial and settings are on the 'Important Data' page the dealer fills in. Search terms: Culligan HE problem found, Culligan Aqua-Sensor, Culligan regen now, Culligan Medallist REG light, Cul-Flo-Valv bypass blue knob.

6 components7 common failuresCulligan
Fleck 5800SXT (and 5800 XTR) softener control valve: quick sheet · OnCall Tech