What Is A Water Pressure Booster Pump? (2024 Guide)

Are you interested in learning what a water pressure booster pump is? And how it works?

Booster pumps can increase your homes water pressure by 10-30 additional psi.

In this guide, I will go over...

  • Exactly whats a water booster pump
  • How booster pumps work
  • The main components of these pumps
  • Extra features

Let's get started with this guide!

what is a water pressure booster pump (how it works)

What Is A Water Pressure Booster Pump?

Picture this: you come home from a long day at work, and all you want to do is take a long hot shower. But guess what?  You turn on the shower, and you barely get a trickle of water. How uncivilized!

The problem is that everyone else in your city is taking a shower at the same time. Water pressure is the lowest in the morning and evening when everybody is home. Fortunately, there is a device that can dramatically boost your water pressure — a water pressure booster pump.

A water pressure booster pump is a mechanical device that will increase your home's water pressure anywhere from an additional 15-psi to 30-psi. When the homes water pressure drops, the booster pump will automatically turn on, raising the water pressure to a target level, such as 55-psi, and then shutoff.

These specialized water pumps are usually installed near the homes main water line, and right after the main water shutoff.

Read Also: What Are The Best Water Pressure Booster Pumps?

How Water Pressure Booster Pumps Work?

A water pressure booster pump really isn't that complicated—it includes a motor, an impeller (fan), housing, control board, and an intake and discharge pipe.

A water pressure booster pumps works by sensing when the flow rate or water pressure drops, and the control board turns on the motor. The motor will start moving the impeller, which acts the same as fan blades, which moves water.

Water gets brought in from the intake pipe, which is connected to your main water line, and the water gets pushed through the impeller, and it gets sent out the discharge line to the rest of your home. As soon as the water pressure reaches the target water pressure (which is adjustable at the control board), the booster pump will stop pumping.

Read Also: How To Install Water Pressure Booster Pumps?

Check Valve

In addition to the basic booster pump components, many municipalities require that a check valve is installed prior to the booster pump — in between the main water shutoff and the pump — and most main shutoffs are located in the basement.

A check valve is simply a one way water valve, so it only allows in water in the direction of the homes water supply.

Just imagine that for some reason the water at your street or well stops sending water to your home, maybe there is a water main rupture. Well, all of that highly pressurized water in your home may flow backwards and out of the home if there isn't a check valve.

If your booster pump runs dry such as if there is a street water main rupture (it happens more often than you think), this is hazardous because it will overheat your pump, warp the gaskets, and may even cause scalding to anyone who is near the pump.

A check valve will prevent water from draining out of your homes piping (it will only move forward into your home) and therefore  will protect your booster pump from overheating.

Read Also: What Are The Best Hot Water Recirculating Pumps?

Pressure Relief Valve

Some municipalities also may require a pressure relief valve installed along with your water pressure booster pump.

You have probably seen a pressure relief valve before because all water heaters are required to have them. The valve is usually connected to a long plastic or copper pipe that goes down to within a few inches from the floor on a water heater. If the water heater becomes overpressurized, it can literally explode, so the pressure relief valve will open up at a pre-set high pressure level and will release water and steam.

The same principle applies to water pressure booster pumps. 

The pressure relief valve is installed along the water line to release the excess pressure in order to protect the pump, and to stop a catastrophic failure. These valves are usually set to be opened if the pressure exceeds around 100-psi.

Read Also: How Does A Hot Water Recirculating Pump Work?

what is a water pressure booster pump & how it works

Bypass Loop

Many homeowners like to install bypass loops with their booster pumps.

A bypass loop is simply piping that routes around your booster pump so that if the pump ever fails, or if you have to replace the pump, or perform maintenance — you will still have water to the rest of your house.

On each end of the bypass loop, you will have a shutoff valve that will be closed during normal operation of the booster pump. But if something breaks, or if the pump starts leaking, you can shutoff the booster pump, open the bypass valves, and still get water to the home.

Read Also: What Are The Best Under Sink Hot Water Recirculators?

Install Location

Water pressure booster pumps are almost always installed near the main water line of a home.

It is usually on the lowest level or basement, and the booster pump needs to be installed after the main water shutoff. You also want a location where you have easy access to the pump for installation and maintenance.

Another thing to consider is that you want a flat or solid surface where you can mount the booster pump. A booster pump makes a lot of vibrations, so a solid and stable mounting location is paramount. I recently wrote a detailed guide on how to install water pressure booster pumps.


Most counties and cities will require a plumbing permit to install a water pressure booster pump.

Installing these pumps is not for the average homeowner since it requires you to cut into the main water line, solder or glue new piping, and install various valves. Hiring a licensed plumber to install a water pressure booster pump is recommended. Please get three quotes before deciding to hire a particular plumber.

You can also purchase the booster pump yourself and just a hire a plumber for labor to save money.

Read Also: What Is Defective Polybutylene Piping?

Leaking Pumps

Probably one of the biggest complaints of homeowners is leaking booster pumps.

It may have been a poor installation, or a manufacture defect, but leaking booster pumps is a common experience with some homeowners.

It's also important that the pump is always filled with water, never allowed to run dry, and to properly prime the pump before using, because this may damage internal components and be related to future leaks.

Some pumps have particular installation steps that other pumps don't have, and its a good idea to carefully read the installation manual even if you have a plumber install it for you.

The Ideal Water Pressure

In my viewpoint, weak home water pressure is when you get 40-psi or lower. For most homeowners, the ideal psi will be around 50-psi.

A water pressure booster pump can increase your home to even higher though, such as 70-psi or higher. However, I wouldn't keep your home water pressure this high except for short periods such as for power washing the exterior. If you keep the water pressure very high, it can damage your piping.

Final Thoughts

The basic purpose of a water pressure booster pump is to increase your homes water pressure anywhere from 10 to 30 additional psi.

You may have low water pressure because you live at a higher elevation than the main water facility in your city or county

If you have a large house with many levels, this can also be a factor as to why you have low water pressure.

A water pressure booster pump in most instances can drastically increase your water pressure. Of course, the downsides will be the upfront cost, maintenance responsibility, and possible leak issues.

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