How to Replace a Well Pump Pressure Switch

Updated: Feb. 07, 2024

Replace a cranky old switch in about an hour.

Next Project

1 - 2 hours






Replace a faulty well pump switch in about an hour, with no special tools or skills required.

Tools Required

  • 4-in-1 screwdriver
  • Adjustable wrench
  • Non-contact voltage tester
  • Pipe wrench
  • Pliers

Materials Required

  • Well pump pressure switch

Well Pump Pressure Switch Adjustment

Your well pump gets its marching orders from the switch mounted on the pressure tank. When the switch acts up (and they all do eventually), you’ll see all kinds of strange behavior. Sometimes the pump won’t turn on — or, if it does, it turns on erratically, or won’t shut off.

The good news? Replacing the pressure switch is cheap and only takes about an hour.

Diagnose a cranky switch by rapping on it with a screwdriver handle. If the pump runs (you’ll hear it click) or quits, you’ve nailed the problem. But even if it doesn’t respond, it’s still worth replacing the switch.

Switches come in three pressure ranges: 20 to 40, 30 to 50 and 40 to 60 pounds per square inch (psi). Always replace your switch with one of the same rating; it’s usually printed inside the plastic cover of your old switch. You should also buy a new pressure gauge and a 1/4-in. by 6-in. galvanized nipple.

Project step-by-step (3)

Step 1

Shut off the power, then disassemble

Flip the breaker to the pump switch and check it with a voltage sniffer to make sure it’s off. The last thing you want to do is electrocute yourself while doing this project. Then disconnect the wiring.

Label each wire with tape and unscrew the conduit locking ring. Next, pull the wires and conduit out of the switch.

How To Replace A Well Pump Pressure Switch Fh11jun 519 06 036 SseditTMB Studio

Step 2

Swap the switch

Close the valve from the pressure tank to the house. Then drain the pressure tank. Next, remove the old switch and nipple. Replace them with new parts.

How To Replace A Well Pump Pressure Switch Fh11jun 519 06 039 SseditTMB Studio

Step 3

Replace the pressure gauge

Slap your adjustable wrench around the flats on the gauge and unscrew it. Wrap the pipe threads with Teflon tape and reassemble. Install the wiring, close the faucet and repower the pump. You’re done!

How To Replace A Well Pump Pressure Switch Fh11jun 519 06 044 SseditTMB Studio