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How to Install and Wire a Pressure Switch

If you have a private well water system, your Pressure Switch is an integral component. The Pressure Switch tells the pump that delivers water to your home when to turn on and off. When the pressure in the system drops to a preset low setting the pump will turn on (commonly known as the cut-on pressure). When the pressure in the system rises to the preset high setting the pump will turn off (commonly known as the cut-off pressure). They can be wired to work with 115 or 230 volts.

Caution! Electricity can be very dangerous, especially if you are inexperienced. Always use caution when working with electricity and turn off the power supply/circuit breakers when testing components or making any adjustments within the electrical system. If you are not 100% confident you can perform any of these tests safely, call a professional.

With basic electrical knowledge, a pressure switch can be installed and wired with a few tools and materials.

Tools and material required: screwdriver, wire strippers, pliers or similar, teflon tape

Optional: forked connectors, crimps, permanent marker

  1. Turn off power to the pump at the main panel.
  2. Test the wiring from the main panel to ensure that the power is off.
  3. Drain all water pressure from the system via a hose bib on the tank tee or nearest faucet.
  4. If you are replacing an old switch, remove existing wires and remove old switch from the system.
  5. Secure the new switch to the jet pump or install on the piping of the existing submersible well pump system. Use teflon tape on the pressure switch inlet to prevent leaks. Click here to see video How to Apply Teflon Tape the RIGHT Way
  6. Remove the cover of the new pressure switch with pliers and set aside. A wiring diagram is normally found on the inside of the cover.
  7. Loosen (do not remove) the screws on the pressure switch terminal with a screwdriver by turning in a counterclockwise direction.
  8. Feed wires from the pump motor and main power supply through the openings on either side of the switch.
  9. Attach the pump motor wires to the two terminals in the center marked “M” or “Load” (T1/T2). Attach the ground wire to the green ground screw.

  10. Attach the power supply from the main breaker to the outside terminals marked “Line” (L1/L2). Attach the ground wire to the green ground screw.

  11. Re-install the switch cover and reconnect the power.
  12. Test the pressure switch for several cycles to ensure that it is working properly.

Would you like to learn more about pressure switches? Click below to check out our RC Worst YouTube videos.

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Do you have further questions about your pressure switch or other parts of your water system? If so, please do not hesitate to call our experts at 855.329.4519.