The well for my home has a 5 hp submersible deep well pump wired to a control box and piped into a 500 gallon holding tank. The holding tank is piped to a 1.5 hp booster pump which then goes to the pressure tank and then about 200' away to the house.

It seems i'm having to replace or rebuild my Booster pump 1-2 times a year because the holding tank will be run dry leaving the pump motor running dry and then it burns out. My holding tank does not have a float switch. So I have to go to the submersible pump control box and manually turn the pump on/off to fill the tank whenever the water is low. Needless to say, that doesn't always happen before the tanks empty.

I want to get a float switch wired into my submersible pump to fill the tank whenever the tank is low. I can't seem to find any knowledgeable people locally to help me figure out what kind of switch I would need to get. The submersible pump wellhead is right next to the tank however the electrical for the submersible pump is run out of the pump house and into another breaker box in a different storage building.

So I know it would be easiest to find a float switch which I can tie into the wiring before it leaves the pump house. I've never purchased a float switch or installed one so i'm just looking for recommendations on a good one that I can tie into the electrical correctly While being able to depend on it operating correctly.

  • This question might help some diy.stackexchange.com/questions/74420/… Shopping/buying questions are a no-no on here, but adjust your to know the specs you need instead.
    – crip659
    Commented Jan 21, 2023 at 22:50
  • 1
    Is the control box over where the breaker is, or near the wellhead and storage tank?
    – Ecnerwal
    Commented Jan 21, 2023 at 23:36

1 Answer 1


Replacing the pressure switch on the booster pump with a pressure switch with a low pressure cutout is an easy (and affordable) way to solve the problem of burning out the booster pump, with much less risk of mechanical failure than float switches, and does not require a float switch that will handle a 5 horsepower motor (few if any will, so then you need a float switch AND a >5 HP contactor to actually start / stop the motor when the float switch says to.)

If you opt (now or later) to use float switches and a contactor to auto-fill the tank, the low-cutout pressure switch will still work in case of float switch failure. I'd also recommend having several float switches with some acting as overrides to shut the 5 HP pump down if the main one sticks on, rather than overflowing the tank until you notice water leaking out.

If the 5 HP pump is already controlled by a contactor, you might just need to have the float switches set to control it. We can't see it from here...

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