How Sump Pump Float Switch Works

The following information is provided to help you learn more about sump pump float switches.


How sump pump float switch works may be a mystery to you; however understanding how the different types of sump pump float switches work is important because each has advantages and disadvantages. Read more about each switch type and which one we recommend and why.

Tethered Float Switch
The tether float switch and the vertical float switch depend upon the movement of the float to trigger the switch which activates the sump pump motor. As the water level increases in the sump pit, the float rises. When the float is raised high enough by the water, the switch is triggered and the sump pump motor turns on. When the float lowers enough because the sump pit water lowers, the switch turns off the pump.
Vertical Float Switch
The diaphragm switch depends upon a membrane to sense the amount of water pressure in the sump pit. As the water level rises, the water pressure increases; the diaphragm (membrane) becomes concave and consequently activates the switch which turns on the sump pump motor. When the water level lowers, the membrane becomes convex and the switch turns off; the sump pump stops running.
Diaphragm Switch
The electronic switch (switch Genius) relies on a probe wire to indicate the presence of water. When the probe is submerged due to rising water, the electronic switch is activated which turns the pump motor on. When the water lever lowers and the probe is no longer submerged in water, the electronic switch turns off as well as the pump motor.
Electronic Switch
The digital level control switch relies on water pressure increase in the sump basin. When the water level rises in the sump pit, the increased water pressure causes electrons to move through the electronic component. The electronic board handles the high initial current. While the current levels out; then a timed relay takes over and turns on the switch which activates the sump pump motor to run. At the end of the relay timed period, the switch turns off and the pump turns off as well. The water level in the pit has lowered as well as the water pressure. As the water pressure builds again, the entire process is repeated again and again.
Digital Level Control Switch
The electronic switch controller (HC6000) relies on the presence of rising water in the sump pit. The greater the amount of water in the pit the less resistance there is compared to the grounded pump motor. The two sensors can detect the extent of resistance from the water as it increases and decreases. When both sensors detect low water resistance (this occurs when the water level rises in the pit above both sensors), the control module is trigger to turn the pump motor on. When the water level is below both sensors, the water resistance increases greatly. The water resistance is greater than the grounded pump motor and the pump will not run. Once the water level covers both sensors again, the control module is triggered to turn the pump motor on. This process is repeated again and again as the pit water rises and lowers.
Electronic Switch Controller
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Advantages and disadvantages of each sump pump float switch type

Tether float switch
The tether float switch is known for the following characteristics:
  • Requires a larger sump pit than the other float switch types because the float swings out as it rises with the water level
  • Gets caught or tangled easier because of the its tether
  • ‘On’ and ‘off’ point can be adjusted somewhat because of the length of the tether
  • Not replaced generally when it fails; instead a new sump pump is purchased
  • Generally cheaper
Tether Float Switch
Vertical float switch
The vertical float switch is known for the following characteristics:
  • Most popular type of float switch
  • Most variety of types – mechanical, magnetic, snap-action.
  • Requires less sump pump pit room than tether
  • ‘On’ and ‘off’ position preset by manufacturer
  • With heavy use after two years, gets stuck easily causing pump motor to burn out
  • Will not get caught easily unless the pump is too close to the sump pit wall
  • Not replaced generally when it fails; instead a new sump pump is purchased
Vertical Float Switch
Diaphragm Switch
The diaphragm switch is known for the following characteristics:
  • Generally performs longer than tether or vertical float switch before failure
  • Diaphragm gets hard and brittle after years of operation and consequently fails to operate
  • Has no moving part to get caught; however a pebble could get stuck in the diaphragm membrane
  • Not replaced generally when it fails; instead a new sump pump is purchased
Diaphragm Switch
Electronic Switch (Switch Genius)
The electronic switch is known for the following characteristics:
  • Newer technology
  • Operation affected by contaminates like calcium carbonate in the ground water collecting on the probe and giving a false reading
  • Requires less pit space than the vertical and tether float switch
  • Generally perform longer than the tether and float switch before failure
  • Some models are built to handle replacement.
  • More expensive than the tether or vertical float switch
Electronic Switch
Digital Level Control Switch
The digital level control switch is known for the following characteristics:
  • Very new technology
  • Requires more pit space than the electronic probe and about the same as the vertical float switch
  • No visible movement; however there is movement inside the level control switch which has a membrane that become concave or convex
  • Life expectancy of relays not established yet. One year warranty offered
  • Can be replaced on pumps built to attach the switch
Digital Level Control Switch
Electronic switch controller
The electronic switch controller is known for the following characteristics:
  • Newer technology
  • No moving parts to wear out or get caught
  • Replacement switch for many sump pump brands because it is external (separate from) the sump pump.
  • Compatible with sump pumps running on less than 14 amps. This includes those using the piggyback switch and those that do not. It can be used with an existing Zoeller, Wayne, Simer, Flint-Walling, Basement Watchdog, Flotec, Superior, StormPro and others
  • The ‘on’ and ‘off’ point is determined by the homeowner
  • Requires no additional sump pit space. The two sensors are attached to the discharge pipe
  • Most reliable sump pump switch technology on the market
  • STAK Enterprises, Inc, the manufacturer, offers a limited lifetime warranty which is unheard of in the industry for sump pump switches
  • Built in alarms for high water and pump motor failure
  • Needs no tools or plumber to install.
  • Uses existing electrical wall outlet
Electronic Switch Controller
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We have installed an Electronic Switch Controller, the Hi-Lo HC6000, and it works so perfectly.

Our sump pump does not run as much now. We live in a high water table area so our sump pit fills with water even when it is not raining.We increased the distance between the ‘on’ and ‘off’ sensors so our pump runs half as much as it did before because the present manufacturers ‘on’ and ‘off’ switch settings are no longer used. We like the fact that the HC6000 electronic switch controller is a piggyback plug so we can use it with our existing submersible sump pumps (we have two sump pits).All we had to do was attach the sensors of the HC6000 electronic switch to the discharge pipe, secure the float of our existing submersible sump pump in highest position ‘on’, plug the HC6000 into the wall socket and plug the submersible sump pump motor cord into the HC6000 controller piggyback plug. No additional plumbing or electrical wiring was required.

Check the HC6000 Electronic Sump Pump Switch now. You will be glad you did.
For your convenience, a purchase link with product detail is found below.

Electronic Sump Pump Switch

HydroCheck HC6000 Hi-Lo Pump ControllerHydroCheck HC6000 Hi-Lo Pump Controller

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