Does a Submersible Pump Need a Pressure Tank?

In this article, we will discuss if a submersible pump needs a pressure tank to work. Do you have a pump that pumps water to your home from the well? Then it is an advantage to learn how the pump works. Being familiar with the components of the pump and how it works can help to troubleshoot in case a problem occurs. Let us find out more about this topic below.

Does a submersible pump need a pressure tank? Pumps do not need a pressure tank to work. There are automatic pumps available in the market that are fitted with a constant pressure controller that starts on demand. On the other hand, it is still recommended that you have a pressure tank most especially if you have a toilet or shower where the pump is rarely operating at a hundred percent. Take note that without a pressure tank, there will be a strain on the pressure switch or controller that can cause it to fail.

What are the benefits of having a pressure tank? How does a pressure tank work? What does a pressure tank do on a pump? Can a well pressure tank be too big? These are some of the questions that we will discuss. Check out the rest of the article below to learn more about this topic.

Does a submersible pump need a pressure tank
Image by Gabor Fejes from Pixabay

What Does a Pressure Tank Do on a Pump?

The pressure tank contains water at the bottom and compressed air at the top. These two things are important when it comes to the proper function of the tank. When you turn on a faucet, the compressed air exerts pressure on the water and causes it to flow out of the tank and into your home plumbing system. The action of the pump allows water from the well to enter the bottom of the tank. The air at the top of the tank is increasingly compressed as the water level rises. When the maximum pressure is reached, the pump will shut off. The pump turns back on to replenish the tank if the water level drops and the air pressure in the tank hit a minimum.

What are the Benefits of Having a Pressure Tank?

One of the benefits of having a pressure tank is that it helps to quiet the pump and minimizes pump hammering and cycling. As you turn on the tap, excess water in the pressure tank will be released to the outlet first. Meaning, there is no need to turn on the pump until the stored water has been used. This extends the pump life and also provides a smooth and quiet operation.

How Does a Pressure Tank Work?

When water is pumped from the well and into the pressure tank, the tank compresses the air until it reaches a certain level. When the faucet is turned on, the air pressure in the tank will force the water throughout the plumbing until the pressure drops to the pressure that is set. This then tells the water pump to turn on and allows water into the tank. The pressure builds until it is restored to its default shut-off level when the faucet is turned off.

Drawdown refers to the amount of water that is delivered by the pressure tank within the time the pump shuts down and the time that it starts again. The amount of water that the pump can draw into the home in one to two minutes will determine the size of the pressure tank as well as the drawdown. You can find tanks that can hold as little as ten gallons, while others can hold two hundred gallons or more. The typical size of pressure tanks that most residential homes have can hold about forty-four gallons. You may need to have a larger pressure tank if your home uses more than the average amount of water or has a well with a low yield. You can also check out this article that we have shared that discusses how long it takes for a well pump to build pressure, We have shared an in-depth discussion about the topic.

✅ Video – Pressure Tank: Operation and Components

R.C. Worst & Co., Inc. shared the video below on YouTube. It discusses how pressure tanks operate and their components. In the video, Chris reviews why you need to have a pressure tank and discusses more its different components. Watch the video for more information.

Water Pump Pressure Tank Sizing

Make sure that you properly keep the amount of run time to the water pump to a minimum by properly choosing the right water pressure tank. Take note that the more the pump runs, the more wear and tear can happen to the electric motor and the pumping mechanism. If you have a small pressure tank, it can cause the water pump to run excessively. Make sure to choose the right pressure tank or one that is larger than is required. Below are steps on how to size the right water pump pressure tank.

Step 1: Consider the Drawdown Capacity

Most pressure tanks are rated by their draw-down capacity. This refers to the amount of water that is stored within the tank before the pressure is low enough to turn the pump back on. Make sure to choose the right drawdown by considering the amount of water that you need for your home. You can ask the manufacturer for some inputs and advice about this concern. You can also check out this article that discusses if you can dump water into a well. We have shared an in-depth discussion about the topic.

Step 2: Decide on the Gallon per Minute

The next step that you need to do is to find the gallon per minute capacity of the pump. You can find this information in the manufacturer specifications manual. For instance, a one-horsepower pump is rated for twenty gallons per minute but can only deliver ten gallons per minute of water from the well source.

Step 3: Amount of Time to Fill a Container

To do this, connect the garden hose to an outdoor spigot that is close to the well. Next, place the end of the hose in a bucket that can fill up to five-gallon. Open the spigot valve and record the amount of time that it takes to fill the bucket. You can also check out this article that discusses why well water turns brown all of a sudden. We have gathered a list of reasons why well water turns brown.

Step 4: Size the Tank Drawdown Capacity

The next thing that you need to do is to size the drawdown capacity of the tanks for every gallon per minute of water that is delivered by the pump.

Step 5: Size for Large Drawdown Capacity

Make sure that you size the tank to a larger drawdown capacity. This is to make sure that the pump continuously running if the household uses a lot of water. See to it that you install larger tanks in areas that have a solid and durable floor. Take note that large pressure tanks can weigh 1600 pounds or more so make sure that you install them in a sturdy place that can hold their weight.

Do I Need a Pressure Tank with a Jet Pump?

If your household relies on the well for the water supply, then you need to have a jet pump and pressure tank. In a normal operation, the jet pump adds water to the pressure tank until it reaches the preset pressure of the pump and shuts off. If the pressure falls below the pump’s cut-in pressure, it will cycle on again which effectively maintains the pressure in your water lines. Contrary to what a lot of people believe, it is not hard to connect the pump to the tank as well as to connect both to the water system. However, before you do this, you need to make sure that you adjust the bladder pressure of the empty tank so that it conforms to the cut-in pressure of the pump.

How Long Can a Submersible Pump Run Continuously?

A Pump can deliver water for up to 20 minutes if it has a continuous-duty motor attached. This is because it is built to have more suction power. Furthermore, the suitability of the pump for deep wells makes it possible to hold and supply more water. You can also check out this article that we have shared that discusses if a submersible well pump needs to be primed. We have shared an in-depth discussion about the topic.

Can a Well Pressure Tank be too Big?

It is recommended that you choose a bigger tank for your home because it will be better for your pump. The reason for this is that bigger tanks allow the pump to have fewer start and stop cycles. However, the disadvantage of having a big tank is that it could pump the well faster than it could recover, but this is a rare occurrence. We have also written this article titled; at what depth should the submersible pump be installed? Check out the article for more tips on submersible pump installation.

Can You Run a Submersible Pump without a Pressure Switch?

For safety purposes, it is recommended that the pump should have a pressure switch and install a small tank or a Pside-kick. In case there is no tank and pressure switch, you need to make sure that there is no way that the water will cut off anytime the pump is running. Otherwise, you will risk burning out the pump.


In this article, we have discussed if a submersible pump needs a pressure tank. While there are automatic pumps that do not need pressure tanks, it is recommended that you have a pressure tank for normal pumps. The pressure tanks will extend the lifespan of your well pump and also maintain water pressure throughout your home. It is also a necessary tool to avoid burning the pump. You can find a wide array of pressure tanks that you can choose from. Thank you for reading!

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