DIY Network

How to Install a Pressure Booster System

Find out how to add more pressure to a home plumbing system by installing a pressure booster system with these step-by-step instructions.

More in Plumbing

installing a pressure booster system

Step 1: Test the Water Pressure

A pressure booster system attaches to the main water line. A pressure switch turns on the pump, which pushes the water through a tube into the tank. One side of the tank has pressurized air, which pushes the water up and out of the tank into the plumbing system.

To find out how much water pressure is in the home, attach a pressure gauge (Image 1) to an outside spigot. If the pressure reads below 30 PSI, the water pressure is low.

When looking to purchase a pressure booster system, choose a model number (Image 2) that’s closest to the number of fixtures in the home.

Step 2: Pressurize the Tank

Make sure the tank is pressurized before installation.

Next, take the cap off the stem on top of the tank.

Use a tire gauge to check the pressure. If the pressure is wrong, refer to the manual for further instructions.

Step 3: Drain the Water Lines

Open a faucet at the highest point in the house.

Shut off the main water valve. Turn on an outside spigot.

Step 4: Choose a Location

Choose an area that doesn't drop in temperature below freezing. An outlet should be close by to provide power to the unit.

Try to place the unit near the main water line that comes into the house. This line will be tapped into before it splits to the remainder of the house so that the pressure will affect each fixture.

Shut off the water at the main using a curb key.

Step 5: Replace the Water Valves

If needed remove and replace the old water valve located on the water line using a pipe cutter (Image 1).

Extend the water line on both sides of the valve by soldering on new piping.
Assemble and solder (Image 2) any parts to be attached to the unit. This will give them time to cool before installing.

Attach the adapter to the discharge on the unit (Image 3).

Step 6: Construct the Bypass System

Construct a bypass system for the intake line. This will allow water to bypass the unit if the need should arise.

Solder the bypass system into place. Make sure all valves are open to prevent heat from building up.

Wait to connect the bypass to the house until the check valve has been installed.

construct bypass system for intake line

Step 7: Install the Valves

Tip: A check valve prevents water from flowing backward into the unit allowing the water pressure to build.

Solder the adapters to the valve before attaching.

Solder the male adapter 'T' (Image 1) that holds the pressure relief valve, then connect the discharge line to the house feed.

Next, connect the intake line to the check valve.

Install the pressure relief valve (Image 2).

Then install the pressure gauge onto the threaded fitting (Image 3) on the unit.

Step 8: Service the Water Lines

Shut off the ball valves.

Turn on the outside spigot and turn on the water at the main. Check all pipe connections for leaks.

Open the bypass valve. Turn on the faucet at the highest point in the house to purge the air from the water lines.

Shut down the bypass and then open the service valve to let water flow into and out of the unit.

Step 9: Thread the Electrical Wires

Open the access cover on the unit to thread the electrical wires into the pressure switch.

Next, connect the two black wires together, then secure with a wire nut and electrical tape.

Bring the ground wire to the pressure switch and then tighten down under the green ground screw.

Connect the white wire to the appropriate lug on the pressure switch and tighten. Replace the cover.

thread electrical wires into pressure switch

Step 10: Manually Adjust the Pressure

Plug the unit in, then turn the switch to the 'On' position.

If the system doesn't kick on, the pressure is too low. Manually override the switch for 10 seconds to get the pressure to the proper range.

Finally, allow the unit to run through a cycle.

manually adjust pressure