Float Switch
A float switch is the level sensor that turns a sump or ejector pump on as water rises and off as it drains, using a buoyant float that moves with the water.
The float is the brain of an automatic pump. As water in the pit rises, the float rises with it, and at a set height it trips a switch that powers the pump. When the water drops back down, the float falls and cuts the power. A tethered float swings on a cord, a vertical float slides up and down a rod, and a diaphragm or electronic switch senses pressure instead, but all do the same job of starting and stopping the pump at the right levels.
Float failure is one of the most common reasons a pump that looks fine simply will not run during a storm. The float can get hung up against the pit wall or the discharge pipe, the cord can tangle, or the internal switch can wear out and stop making contact. The classic symptom is a pump that stays silent while water rises, or one that runs nonstop because the float never falls far enough to shut it off.
Testing a float is simple: lift it by hand and the pump should start, then lower it and the pump should stop. Because it is the part most likely to stick, it is the first thing to check before assuming the whole pump has died.
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- Well Pump (Submersible & Jet) : A well pump is the motorized pump that draws water from a private well and pushes it into the home’s plumbing, either lowered deep inside the well casing or mounted above ground.
- Well Pressure Tank : A well pressure tank stores pressurized water and a cushion of air so the well pump does not have to switch on every time a faucet is opened.
- Grinder Pump : A grinder pump shreds household waste into a slurry and pumps it under pressure to a sewer or septic line, used where the distance or uphill run is too much for a standard ejector pump.