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Well Tank Pressure Guide: Tips & How to Check

Scott Winfield
Written by Scott Winfield
Last Updated on

Successfully maintaining the water pressure in your well tank depends on two things: understanding how your well pressure tank works and checking the water pressure regularly.

In this guide, we’ll show you how to check the water tank pressure and share tips that will help you keep the tank working correctly.

How Do Pressure Tanks Work?

Pressure tanks use air pressure to push water from the tank into your home when you turn on a faucet.

A pump fills the tank with well water until the remaining air compresses enough to reach a specified pressure, measured as pounds per square inch (psi). When the pressure inside the tank reaches the psi the tank is set to hold, the water stops.

Well Tank Pressure Tank

When you open a faucet, the pressure in the tank pushes water through the pipes. The pressure drops, and when it hits a specific psi, the pump activates and fills the tank again.

The maximum pressure in a tank is usually 40 to 60psi, so water stops flowing into the tank when the air compression hits that level. Water pumps in again when the pressure drops to approximately 20 to 40psi.

How to Check Water Tank Pressure

You’ll need a dial or digital pressure gauge to check your water tank pressure:

  1. Turn off the power at the breaker to disconnect the electricity from the tank.
  2. Open a faucet to drain the tank completely. The air regulator on the tank will show 0psi when it’s empty.
  3. Find the air valve, known as the Schrader valve. This valve is usually on the top, covered with a silicone or rubber cap like the valve stem on a tire.
  4. Remove the cap, and unscrew the metal valve cap.
  5. Use your pressure gauge by pressing it onto the valve to see its reading.

What PSI Should My Well Tank Be?

The psi reading of your tank should be 2-3psi below the tank’s cut-on psi setting. The cut-on psi is the pressure level in the tank that triggers the pump to pull water from the well into the tank.

If you don’t know the cut-on setting, look for the tank’s pressure switch and remove the cover. The inside of the cover has a specifications sticker showing the cut-on and cut-off pressure.

The lower number is the cut-on pressure that triggers the pump, while the higher number is the cut-off pressure that stops the water flow. For instance, a tank that says 20-40 has a cut-on psi of 20 and a cut-off psi of 40.

When you check your tank’s pressure after turning it off and draining it, its psi should read 2-3psi below the cut-on number. If a tank’s cut-on psi is 30, the pressure while the tank is off and empty should read no more than 28psi.

Is 70 psi Too Much Water Pressure?

A water pressure of 70psi is probably not too much pressure unless you have old pipes in your home. Pressure higher than 70psi risks straining the plumbing and damaging the system.

It’s worth noting that 70psi drains the tank faster and gives the pump motor less resting time, which will wear the device out more quickly. Plus, the higher the psi, the more water you’re using.

Is 100 psi Water Pressure Too High?

A water pressure of 100psi can seriously damage your home’s plumbing. Appliances that use water, such as dishwashers and washing machines, are at risk of damage, too. 

Is 120 psi Too High for Water Pressure?

If you see that your water pressure gauge is hitting 120psi, it indicates a significant problem. You should immediately turn off the water supply, check what’s wrong, and call a professional if need be.

A water pressure of 120psi is too high and will cause faucet drips, pipe leaks, and damage to wet appliances. That much psi will strain the entire plumbing system of your home.

How to Change Pressure Tank Settings

To change the settings of your pressure tank, disconnect the power supply for safety by turning it off at the breaker.

How to Change Pressure Tank Settings
How to Change Pressure Tank Settings

You’ll need a ruler, tape measure, or a way to measure fractions of an inch (or millimeters) and a ⅜-inch socket (unless the nut on your pressure switch is a different size).

You’ll see two rods with springs around them and nuts at the top of the pressure switch. The large one sets the cut-in psi level.

The smaller rod sets the differential between the cut-on and cut-off psi. This nut usually keeps the levels 20psi apart. Don’t adjust this level.

On the larger spring, measure from the top of that bolt down to the first exposed thread above the nut on top. If you lose track of how many turns or adjustments you’ve made, you can reset it to this length and start over.

To change the tank’s settings:

  • Turn the nut counterclockwise to decrease the cut-in psi level.
  • Turn the nut clockwise to increase the cut-in psi level.
  • Generally, one full rotation of the nut equals a change of 2-3psi.
  • The cut-off pressure will increase (or decrease) by the same amount, so they’ll remain 20psi apart unless your tank has unique settings.

For example, one full turn counterclockwise on a tank with a cut-on pressure of 30 would lower the setting to 27 or 28psi instead.

Three full turns clockwise on a tank with a cut-on level of 40psi will increase it by 8-9psi to 48 or 49psi. This change also increases the cut-off pressure by 8-9psi.

What Causes a Well Pressure Tank to Lose Pressure?

Your well pressure tank can lose pressure for a few different reasons.

If you use a lot of water and the tank doesn’t have time to refill, the pressure will drop. If this happens often, it means that you probably have a pump that’s too small to keep up with the amount of water you use.

Leaks are another reason for low pressure. A leak in the tank or any of its valves will cause the tank to lose pressure, just like a ruptured bladder in a bladder tank system will.

Sometimes a dirty supply pipe coming from the tank can cause the water pressure in the home to drop because less water will be passing through, even when the tank pressure is normal.

What Happens if Well Pressure Tank is Too Low?

If your well pressure tank pressure setting is too low, water will flow through your pipes more slowly, as there will be less pressure behind it.

Appliances that use water will take a longer time to fill up, and the water coming from faucets, taps, and showerheads will flow slowly, sometimes at a trickle.

Adjusting the cut-in psi of the tank will raise the pressure in the tank and provide higher water pressure for your home.

However, if the tank loses pressure repeatedly, it could be due to a ruptured or leaking bladder in a bladder pressure tank. This will cause the bladder to stretch too far as too much water enters the tank. Pipe leaks can also reduce pressure.

When you suspect leaks, calling a professional to check the system may be helpful. In the end, they’ll either fix the issue or tell you that you need to replace the tank.

What Happens if Well Pressure Tank is Too High?

If the pressure in your well tank is too high, it can cause the pump to cycle on and off rapidly. The high pressure can rupture valves such as the Schrader valve.

When you measure the pressure in the tank while it’s off and drained, if the pressure is higher than 2-3psi below the cut-in psi level, you should bleed the tank by letting air escape until the pressure lowers.

Press the pin in the center of the Schrader valve to release air for one to two seconds. Measure again, and repeat until the pressure is at the right level.

How Do I Know if My Well Pressure Tank Is Bad?

Some commons signs of a bad pressure tank are:

  • A water pump that cycles constantly or erratically, often shown through a high electricity bill;
  • Pressure fluctuating up and down on the pressure valve attached to the tank;
  • Air sputtering from faucets when you turn them on;
  • A drop in water pressure or no pressure;
  • Water that comes out too hot because of air in the cold water supply;
  • Clicking sounds that indicate the tank might be full of water, known as a waterlogged tank;
  • Water spurting from the air valve when you press the pin;
  • Leaks from the tank

How Do You Clean Pressure Tank?

Like every water-related appliance, pressure tanks can also get contaminated by sediment. To clean your water pressure tank, you can follow these nine steps:

  1. Turn the power off at the breaker.
  2. Attach a garden hose to the spigot on the bottom of the tank.
  3. Get the other end of the hose to drain outside or into a large bucket, then open the valve to drain the tank.
  4. Carefully use pliers to remove the air regulator on top of the tank that shows the pressure inside the tank.
  5. Unscrew the access hatch on top of the tank and remove it.
  6. Wipe out the inside of the tank and remove sediment or particles at the bottom of the tank.
  7. Use steel wool to scrub any sediment deposits stuck to the tank.
  8. Screw the hatch into place, and replace the air regulator.
  9. Remove the hose and close the drain valve, then turn the breaker on to let the clean tank fill.


Pressure tanks use pressurized air to push water through so that it can reach the faucets in your home. Most of them are set at 40 – 60psi of water pressure. If you’re not sure about yours, you should check your product’s instruction manual or contact the manufacturer.

A higher level of psi inside the tank means that the water is pushed too forcefully by the tank, so it can damage the piping system, the appliances that use water, and even the faucets. If this is the case, letting some air escape the tank by using the pin on the Schrader valve of the tank will help you lower the pressure (number of psi).

Low pressure, on the other hand, might be a sign of damage to the tank or too much sediment contamination in water. It may require the services of professionals to fix. In extreme cases, you may even need to purchase a replacement tank.

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Scott Winfield
Scott Winfield
My name is Scott Winfield and researching and writing about water filters and other strategies to purify water has become my full time passion in recent years. I'm glad that you found our site and you can look forward to authoritative and well researched content here to help you get the best in water.
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