How to wire a 220-well pressure switch: (7 easy steps)

The well-pump pressure switch is an integral part of delivering water throughout the house; when it leaves, it can lead to serious disturbances in your life! In this guide, you will learn:

  • How to wire a 220-well pressure switch.
  • Wiring for two types of well pump switches.
  • Signs that your button is ready to be replaced.

Do you think that the water pressure is much lower than normal? Do you think your well pump is constantly turning on and off? These are signs that your pressure sensor is bad. If you are here, you are trying to decide if you can do it yourself. I’m here to tell you: yes, you can if you follow our simple guide!

As a licensed electrician, I ask that if you feel uncomfortable or encounter problems at any time while working on the well-pump pressure switch, please stop and call your local electrician to help finish the job. Keep reading to learn the 4 steps on how to wire a 220-well pressure switch!

When do I need to replace the pressure switch?

Most pressure switches will last for many years without the need for replacement. Of course, issues can arise, and many downhole pressure switches corrode or fail in less than a year. Some homeowners replace the switch every year to avoid issues with the well.

During the annual well inspection, the inspector should always check the well-pressure switch and notify you when it needs to be replaced.

How to wire a 220-well pressure switch?

Before jumping straight into the steps, first get a proper understanding of the 220-volt well pump wiring diagram. So, when we finally do the wiring, it will be possible to be on time quickly.

You will find 2 types of well pump pressure switch wiring diagrams. One good pressure switch cover is two screws, and the second pressure switch is three-wire. And after checking some pressure switch wiring diagrams, we can say that the 220V well pump wiring switch mainly uses a 2-wire submersible pump.

In the pressure switch, control cabinet 2, the hot wire enters from 2 opposite sides – one from the borehole pump and the other from the electrical panel. Here, you need to make a connection from the electrical panel to the pressure pump.

At this time of connection, you must be careful not to confuse the neutral with the hot wire connections. To do this, you need a few tools:

  1. Screwdriver.
  2. Wire stripper.
  3. Several crimps.
  4. Voltage meter.
  5. Fork connectors.

1. Turn off the power to the pump

The first and most important step for you is to disconnect all connections to the high-pressure pump and motor wires. This step must be known to avoid electric shock.

Tip: Trying to do plumbing work on live wires can be extremely dangerous.

2. Make sure the power is off and relieve pressure

Even if you are sure that the correct circuit has been broken, it is still a good idea to check the wiring to make sure the electricity is off. The easiest way to test is to use a multimeter, VOM, or voltage detector to test the circuit breaker.

Now that the power to the pump is off, it’s time to find the switch box and start the repair.

3. Find a switch box

Now find a switch box to connect the electrical panel to the pump. Look closely, you’ll find a D-sized square switch box.

In a two-wire pumping machine, this switch box is located inside the bottom of the pumping machine. And in the case of a 3-wire machine, this control box primarily lies outside the pumping machine.

2 wire machines

When it comes to a 2-wire downhole pump, all starting components are inside the pump. So, the switch box is located inside the bottom of the borehole pump. Two wire pumps have two black wires plus a ground wire. This means there are only three pressure switch wires.

Tip: Starting components here refer to starting relays, capacitors, etc.

3 wire machines

Compared to the 2-wire machine, the 3-wire machine has a separate pump control box. You can install the control box outside. 3-wire pumps have three wires (black, red, and yellow) plus a ground wire.

Tip: For this demo, we will be using a 2-wire well pump. Keep this in mind when you follow the process of connecting the pump.

4. Remove the old pressure switch

Now it’s time to remove the old pressure switch. But first, take a photo before disconnecting the wires from the old switch. This will help when connecting a new well pressure switch. Then carefully loosen the terminal screws and pull out the wires. Next, take out the old switch.

Tip: Before removing the old switch, you need to run the nearest faucet. By doing this, you can remove the remaining water from the tank.

5. Open the switch cover box

Use any flat screwdriver and open the switch box cover. Sometimes you can find this box open. This time, you don’t need to spend money to open it.

6. Protect your wired connection

Now it’s time to connect a new pressure switch for 220 wells. First, you will need to disconnect the original electrical wiring from the device. We suggest taking a picture of the wiring before disconnecting anything. This works like your pressure switch circuit and will make it much easier to reconnect the wires during installation.

Wire marking is also a good idea and can make any future repairs easier. Label each wire and terminal when disconnecting wires. You will then need to relieve the water pressure from the water tank. You can simply go to the nearest faucet and let it run for a few seconds to depressurize the tank.

Now that the tank is partially or empty, you can safely unscrew the old parts and get ready to replace the working well pressure switch. You may get a little wet during the transition, but you can easily plug any leak with your finger during the repair.

If you have photographed the wiring and labeled the connections, connecting a new downhole pressure switch will take a few minutes. (If you haven’t, you can find a 220V well pump pressure switch wiring diagram online. However, make sure you understand the diagram and that it applies to what you’re looking for).

Now it’s time to secure the wired connection. Here’s what you need to pay attention to during installation.

  • There should be four electrical wires.
  • Two line wires run from the power supply to two screws marked “line” on the switch.
  • The two wires of the line output are connected to the power supply of the water pump.
  • Be sure to connect the “hot wire” and “neutral wire” to the correct points.

Be sure to use pliers, wire nuts, or wire connectors to ensure a safe and secure wire connection.

Tip: If necessary, use a wire stripper to strip the wires.

7. Close the switch box

Double-check the connections are secure: there are no loose fork connectors and the ground screw is tight. Carefully fold the excess wire so that the cover can be easily put back into place without pinching the wires. Once completed, you can turn the switch back on.


Do you still have questions about the wiring of the well-pump 220? Here are some of the most common questions I get asked about downhole pressure switches.

How many wires does a pressure switch have?

Most switches only use 5 or 6 wires! To find your switch, check out three common places where switches are installed:
– On the jet pump or directly on the well pump, which is located next to the water pressure tank.
– On the water tank tee or in line with the water pipe that is next to the water pressure tank.
– On the accumulator itself.
For the most part, 220V well pressure switches use a two-wire submersible pumping unit.

Can I run my well without a pressure switch?

Yes, the well pump will work without a well-pressure switch. However, this is not the best situation, considering the consequences. But, you may ask why? Allow me to explain. Notifying the well-pump when to turn it off and on is the primary job of the pressure switch. This process goes according to the PSI value of the water.
Most household pressure switches are rated to run water at 30 psi, and when the pressure reaches 50 psi, the water flow stops immediately. You can easily change the PSI range to suit your needs. The pressure switch prevents the risk of pump burnout. At the same time, it will not allow waste water and electricity.

Why should I replace a pressure switch?

Over time, the well-pressure switch can corrode or fail. A bad pressure switch can cause your home to have no water pressure or too much pressure. It can also cause the pump to run continuously and waste power.
If you notice corrosion on the switch, it may be time to replace it. A faulty pressure switch can also cause your well to not pump water at all, which can cause emergencies in your home.

Where do the pressure switch wires go?

The wire from the switch box goes to terminals “1 and 4” or terminals L1 or L2. A wire from the motor goes to the load terminals “2 and 3” for a 2-wire system, R and Y, and B for a 3-wire system. Before installation, make sure the wiring and electrical connections of the wire are correct.

Why does my well pump have 3 wires?

Three wire pumps will have black, red, yellow, and green wire. Black is grounded and does not count as one of the three wires. The remaining 3 wires are usually located in the switch box installed on the outside of the pump system. Thus, a three-wire system is cheaper to repair than a two-wire system.

How to reset the well-pump pressure switch?

If you have a standard pump with a lever stuck to the switch box, push it up until you hear the pump start to sound and hold until it rises to 30 pounds. Then let it install. You will see how the pump pumps water with perfect stability.

How to connect a 230-volt pressure switch?

Make sure the power is off, then run the wires to the switch. Power wires L1 and L2 are connected to the two outermost ground screws of the terminal block. The motor wires will land on the two center propellers labeled M or T1 and T2.
Then the ground wire will sit on the green ground screw. Hide the wires well, so you can put the cover back on and turn the power back on.

Does a well-pump need to be grounded?

Yes. You must ground it. Because most submersible pumps have a metal casing and junction box, you should ground the well pump properly. In addition, these machines are constantly exposed to water. Thus, there is a high risk of electric shock or fire.


I hope this step-by-step guide to connecting a 220-well pressure switch will help you complete a task as simple as replacing or installing a pressure switch on a pump.

Otherwise, if you are not very familiar with electrical wiring, this guide will help you learn how to deal with this issue yourself. In any case, we will be happy to help you a little. Until next time, take care of yourself.

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James Cole

Considering that most people continue to pay the masters in the service for a consultation, I decided to create my blog.

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