From a slow trickle to a hose jet stream, the wrong water pressure can take the comfort out of your shower. Calling in a professional to adjust the pressure can cost between $100 to $150 for a house call, whereas adjusting it on your own only requires a wrench.
Adjusting the pressure switch on your well pump is a quick and easy skill to learn that can bring peace back to your shower time. Whether you’re turning up or toning down, this guide will walk you through the steps to get your pressure switch set just right.
What Is a Pressure Switch?
The pressure switch is the part of your well water system that regulates water pressure, ensuring you have a consistent flow to your showers, taps, and toilets. Most well systems have an automatic pressure switch that adjusts to pressure changes, but some standard switches don’t adjust on their own.
Whether you have a non-automatic switch or you’d just like to change the pressure to something you find more comfortable, knowing how to adjust your pressure switch puts the power in your hands.
Turn Off the Power Breaker
Always start by disconnecting the power to your pressure switch before you make any adjustments. Your pressure switch power supply can usually be found on your main power breaker, sometimes under a label like “well pump” or “water pump.”
If you’re not sure which switch connects to your well system, give your local electrician a quick call—it never pays to take risks when you’re working with electricity.
Remove Your Pressure Switch Cover
The pressure switch cover is typically a small plastic cube, usually gray or black in color. It’s often held in place by a nut that you can untwist by hand or with a wrench.
Inside the cover, you’ll find a guide to your pressure switch’s factory settings. This can also include important details like upper and lower pressure limits.
Identify Cut-In and Cut-Out Settings
Photo: Елизавета Скобелкина / Adobe Stock
Well pump pressure switches include two settings: cut-in and cut-out. Cut-in pressure is the low-pressure point where your well pump starts, while cut-out pressure is the high point that turns off the pump.
There’s a range between these two points, called the differential. For example, it could go from 30–50 PSI (pounds per square inch). The standard differential is 20 PSI. Lowering the cut-in point reduces your water pressure, say from 30–50 PSI to 20–40 PSI, whereas raising it will give you a more forceful pressure.
You’ll usually find two nuts inside your pressure switch: a large center nut and a small nut above or below. It’s always a good idea to look at the inside of the cover to check which is which, but on most systems, the larger center nut controls cut-in and cut-out pressure.
Turn the Cut-In/Cut-Out Nut To Adjust the Pressure
Turning the large center nut will adjust both your cut-in and cut-out pressure, lowering or raising the overall pressure. You’ll still have the same differential (normally about 20 PSI).
Measure and record the nut position before you make any adjustments. This can help you track how many PSI you’ve adjusted and return to the factory settings if you ever want to reset your pressure switch.
To lower your pressure, turn the nut counterclockwise. To raise it, turn the nut clockwise. As a general rule, one full turn of the nut will change your pressure by about 2–3 PSI.
Optional: Adjust the Pressure Differential
The second nut on your pressure switch changes the differential—for example, you could go from 30–50 PSI to 30–45 PSI. This is rarely used, and you won’t need it if you only want to raise or lower your water pressure.
Changing the differential can also prevent your pump from properly turning off, and can ultimately shorten the lifespan leading to a costly well pump replacement or pump repair. It’s generally not advisable to turn this nut unless you have a specific need, like if the previous owner had set the differential to something other than 20 PSI.
Test Your Pressure
Once you’ve adjusted your pressure switch, replace the switch cover and turn the power back on. When the pump turns on, record the low PSI and then record the high PSI again when the pump turns off. This will show you your new cut-in and cut-out pressures.
It can sometimes take a few tries to get the pressure where you want it, but it’s always a good idea to start slow and then adjust more later. If you need to make any adjustments, remember to turn off the power before you start.
Most well pump pressure switches have a factory setting of 30–50 PSI. There’s some flexibility with this if you’d like a lower or higher water pressure, but remember that it should sit 2–3 PSI above your tank’s general pressure setting.
The inside of your pressure switch cover will usually indicate minimum and maximum settings—going below and above the numbers might damage your well pump.
The easiest way to identify a bad pressure switch is when the well pump doesn’t turn on and off. You can check this by monitoring your well pump pressure—if it drops below the cut-in point and your well pump doesn’t start, or it hits the cut-off point and your well pump doesn’t stop, it may be time for a new switch.
Normally, when your well pump turns on or off, you’ll hear a small click. This isn’t anything to worry about, but it can be a problem if it’s clicking continuously. This can indicate that the well pump is short cycling—the pump continuously turns on and off.
This can wear out the motor and provide uneven water flow. If this happens, you may need to get it looked at by a well pump professional to see if you need to repair the switch or pump.
Mika is a professional writer with a knack for home improvement projects, which she always tackles with an eye to art and design. She loves a good renovation and upcycle, and believes that there’s always a way to reinvent your home.
Mika is a professional writer with a knack for home improvement projects, which she always tackles with an eye to art and design. She loves a good renovation and upcycle, and believes that there’s always a way to reinvent your home.
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