Float switch and level sensor repair
A grinder pump float switch is the tethered ball that tells the panel when the tank is full enough to pump and when it is empty enough to stop; a third float raises the alarm. When a float sticks, fouls with grease or fails, the pump runs constantly, never runs, or cycles every few minutes. Grinder Pump Gents repairs and replaces float switches and level sensors on grinder stations across Baldwin and Mobile counties.
Not every station has floats. E-One stations sense the level with pressure switches built into the pump core, so an E-One with a level problem is a different repair, and it is covered here too.
Plate IX. The float keeps better time than the watch, until it does not.
- Owner-run: Brandon Byrd does the work
- Alabama master plumber MP-4462
- More than a decade on grinder pumps
- You see the failed part before any repair is agreed
- Emergency line open 24/7: (251) 850-8031
How level sensing works on each brand
Keen simplex stations, the ones BCSS installs, use three floats: off, on and alarm. Liberty's automatic ProVore uses a piggyback wide-angle float that switches the pump on at roughly 12 to 16 inches above the basin floor and off at about 6 inches; the pump cord plugs into the float switch, and the switch plugs into the receptacle. Zoeller's Shark grinders switch on at 13 inches and off at 5-3/4. Barnes offers either integral floats or a sealed pressure switch. E-One uses differential pressure switches with an equalizer for atmospheric changes, which is why there is nothing to hang up on the tank wall, and why a level fault on an E-One is diagnosed through the core and the panel instead.
What goes wrong
The manufacturers' troubleshooting tables name the same handful of causes.
- A float hung on the basin wall, a cord or the pump: Keen, Liberty and Barnes all list it under a pump that will not shut off, and Liberty lists float obstruction under a pump that will not start.
- Grease or powdered soap scum on the floats, which Gulf Shores Utilities names as a common failure cause, and which Keen says can stop a station outright.
- Floats that have shifted so the on and off points are wrong, causing short cycling or letting grease build up when the off level is set too high.
- A failed float switch, on Keen's list of reasons a pump will not run and Liberty's list of reasons it will not stop.
- Fire ants and insects in the panel or float cords, which the Gulf Shores Utilities page mentions by name.
- Floats in turbulence, which Keen says makes the contactor chatter.
What we check, and what you should not
Each float is lifted through its range by hand with the panel in the right mode, the switch point confirmed, the cords and clamps checked, and grease cleaned off. On a Liberty piggyback setup the switch and the pump are tested separately: Liberty's manual describes unplugging the pump cord from the switch and running the pump directly through the breaker as a way to isolate a failed switch, and says the receptacle must be on a 20 amp circuit. That is a technician's test, done at the breaker, not something to try with wet hands in a yard. On an E-One, the pressure switch and equalizer are checked at the core.
From the outside, the homeowner's job is to notice: a pump that runs when nothing is draining, a hum that never stops, or an alarm that comes and goes. Do not reach into the basin to free a float. The tank holds sewage gas, and the pump can start while your arm is in it.
Where this work is allowed
Float and level sensor work is a repair, and repairs are open to the owner's plumber on each owner-maintained system in the two counties: BCSS and Gulf Shores Utilities, Fairhope and Daphne, Riviera's Foley system, North Baldwin and Loxley, Orange Beach, and MAWSS. Riviera's handbook lists floats among the items that are the customer's responsibility. On SAU, MCWS and MAWSS decentralized systems the utility maintains the level controls with the pump.
Request service from this page
Your name, a way to reach you and what the pump is doing. That is all we need to start. Town and utility are optional.
Sewage backing up or overflowing? Stop using water and call now: (251) 850-8031. On a utility-owned pump, call your utility first.
How the visit goes
Step 1: Symptom first
Constant running, no running, short cycling or a wandering alarm each point to a different float, so we start with what you saw.
Step 2: Panel mode and inputs
Hand-Off-Auto set correctly, float inputs read at the panel, contactor behaviour noted.
Step 3: Lift and test each float
Every float cycled by hand through its switch point; cords, clamps and tether lengths checked.
Step 4: Clean, reset or replace
Grease and scum removed; a shifted float reset to the maker's on and off heights; a failed switch replaced with the maker's part.
Step 5: Prove the cycle
Tank filled and pumped down with the on, off and alarm points confirmed, and the panel alarm tested.
Check who can do the work
Your sewer utility decides who can repair or replace the pump. Compare the rules by utility before scheduling the work.
Questions people ask
My grinder pump float is stuck. Can I free it myself?
No. The manufacturers tell owners not to repair the unit themselves, and the basin holds sewage gas with a pump that can start at any moment. Stop using water, silence the alarm, and book the repair.
What is a piggyback float switch?
A float switch with its own plug on the back. The pump cord plugs into the float, and the float plugs into the wall receptacle, so the float makes and breaks power to the pump. Liberty's ProVore and Omnivore automatic models use one, on a 20 amp circuit for the ProVore and a 30 amp breaker with a 6-20R receptacle for the Omnivore.
How do you test a float switch?
By lifting the float through its switch point and watching the panel or the pump respond, then checking the float's cord and the switch itself. On a piggyback switch the pump is also run directly through the breaker to prove the pump is fine and the switch is the fault. These are technician steps at the panel and breaker.
Why does my grinder pump keep cycling with no water running?
Usually a float set wrong, a leaking check valve letting water run back into the tank, ground water entering the basin, or a leaking fixture in the house. Liberty, Keen and Zoeller all list those causes for a pump that starts and stops too often. The float is checked first because it is the quickest to prove.
Does an E-One pump have a float switch?
No. E-One stations use integrated pressure switches instead of floats. A level fault on an E-One is diagnosed in the core and the panel; it is the same service, just a different part.
Sources and facts
- Keen simplex: three floats, Off, On and Alarm; pump will not run causes include a defective or restricted float; will not shut off causes include a restricted float, H-O-A in HAND and air lock; chattering contactors mean failing floats or turbulence. Keen Pump General O&M, Control Panel, keenpump.com/… p.2-5; Keen Pump O&M-KPCG, 1 HP Progressive Cavity Submersible Grinder Sewage Pumps, keenpump.com/… p.9 (read 2026-11-04)
- Liberty ProVore automatic models: piggyback wide-angle float, on about 12-16 in above the basin bottom, off about 6 in; in switch failure the pump cord can be plugged directly into the outlet and run through the breaker; receptacle on a 20 amp circuit; Omnivore piggyback needs a 6-20R receptacle on a 30 A breaker. Liberty Pumps Installation Manual 2399000E, ProVore 1 HP Residential Grinder Pumps, www.libertypumps.com/… p.5, 8-9; Liberty Pumps Installation Manual 5647000N, Omnivore 2 hp Grinder Pumps, www.libertypumps.com/… p.8 (read 2026-11-04)
- Zoeller Shark 803/805/807: automatic on at 13 in, off at 5-3/4 in. Zoeller FM2903 Installation and Service Instructions, 803/805/807 Grinder Pumps, zoellerpumps.com/…; Zoeller FM2882 technical data sheet, zoellerpumps.com/… (read 2026-11-04)
- Barnes OGV: integral on/off and alarm floats (AUF) or an ESPS-150 environmentally sealed pressure switch (AUE). Barnes (Crane Pumps and Systems) Installation Manual, Submersible Grinder Pump OGVF/OGVH, d1pkofokfruj4.cloudfront.net/… p.4 (read 2026-11-04)
- E-One: differential pressure switch level control with an equalizer for atmospheric pressure fluctuations; integrated pressure switches instead of floats. E/One Product Family brochure (LM000365 Rev D), eone.com/… p.2; E/One DH071 product page, eone.com/… (read 2026-11-04)
- Gulf Shores Utilities: failure causes include grease or powdered soap scum on floats and fire ants; use liquid soaps. Gulf Shores Utilities, Grinder Pump page, www.gulfshoresutilities.com/grinder-pump (read 2026-11-04)
- Keen/BCSS: the station stops if grease obstructs the level sensors; grease and solids accumulate when the OFF switch is set too high. BCSS-distributed Grinder Station User Guide (Keen KPCGSL21 station with generator connection), www.baldwincountysewer.com/… p.14; Keen Pump O&M-KPCG, 1 HP Progressive Cavity Submersible Grinder Sewage Pumps, keenpump.com/… p.9 (read 2026-11-04)
- Liberty: pump will not start causes include float obstructed, defective float; will not turn off causes include float hung on basin, failed panel or float; cycles too often causes include improper float setting, leaking check valve, leaking fixtures. Liberty Pumps Installation Manual 2399000E, ProVore 1 HP Residential Grinder Pumps, www.libertypumps.com/… p.10-11 (read 2026-11-04)
- Barnes: pump will not run or will not turn off when the float is restricted. Barnes (Crane Pumps and Systems) Installation Manual, Submersible Grinder Pump OGVF/OGVH, d1pkofokfruj4.cloudfront.net/… p.12 (read 2026-11-04)
- Keen: short cycling causes include ground water entering the basin, leaking fixtures and floats moved. Keen Pump O&M-KPCG, 1 HP Progressive Cavity Submersible Grinder Sewage Pumps, keenpump.com/… p.9 (read 2026-11-04)
- E-One: do not attempt to repair the unit yourself. E/One Owners Guide (LM000403 Rev G), eone.com/… p.5 (read 2026-11-04)
- Riviera: floats are among the items on the customer's side that are the customer's responsibility. Riviera Utilities, Sewer Policy Handbook sections 7.3-7.4 (file dated 2024-05), www.rivierautilities.com/… (read 2026-11-04)
Related
- How Does a Grinder Pump Work? The Cycle, Step by Step
- Grinder Pump Alarm Keeps Going Off? Why It Returns
- Grinder Pump Alarm Going Off: What to Do Right Now
- Why Is My Grinder Pump Running Constantly? 7 Causes
- Grinder Pump Check Valve and Anti-Siphon Valve Repair
- Grinder Pump Control Panel Repair and Replacement
- Grinder Pump Repair in Baldwin & Mobile Counties, AL
- Who Owns Your Grinder Pump? Rules by Utility, Quoted
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