How to Plumb a Pressure Tank from a Well (Step-by-Step Guide)

If your home relies on a private well for water, you know how crucial consistent water pressure is. Without a properly plumbed pressure tank, you risk pump burnout, inconsistent flow, and costly repairs. How to plumb a pressure tank from a well isn’t just about connecting pipes—it’s about creating a reliable, efficient system that lasts for years. Whether you’re a seasoned DIYer or a first-time homeowner, this guide walks you through every step with clarity, safety, and best practices in mind.

Why Do You Need a Pressure Tank with a Well System?

A pressure tank isn’t optional—it’s essential. Here’s why:

• Prevents short cycling: Without a tank, your well pump would turn on and off every time you open a faucet, drastically shortening its lifespan.
• Maintains steady pressure: The tank stores pressurized water, so you get consistent flow without waiting for the pump to kick in.
• Reduces wear and tear: Fewer pump cycles = less mechanical stress and lower energy bills.

According to the U.S. Department of Energy, well pumps that short-cycle can fail up to 3x faster than those paired with correctly sized pressure tanks.

What Tools and Materials Do You Need?

Before you start, gather these essentials:

✅ Tools:

• Pipe wrench
• Teflon tape (for threaded connections)
• Adjustable wrench
• Pipe cutter or hacksaw
• Screwdrivers
• Air compressor (for pre-charging the tank)

✅ Materials:

• Pressure tank (properly sized—see below)
• Well pump (submersible or jet)
• Check valve
• Pressure switch
• Pressure gauge
• PVC or PEX piping (½” to 1″, depending on flow needs)
• Unions or flexible connectors (recommended for easy maintenance)

💡 Pro Tip: Always shut off power to the well pump at the circuit breaker before starting any plumbing work.

How to Size Your Pressure Tank Correctly

Choosing the wrong tank size is a common mistake. Too small, and your pump short-cycles. Too large, and you waste space and money.

Use this rule of thumb from the Water Systems Council:

Minimum drawdown (gallons) = Pump GPM × 1 minute

For example:

• A 10 GPM (gallons per minute) pump needs at least a 10-gallon drawdown.
• Since most tanks are only 20–30% usable water (the rest is air), a 40–80 gallon tank is typical for residential use.

For more on tank physics and air-water balance, see Wikipedia’s entry on pressure vessels .

Step-by-Step: How to Plumb a Pressure Tank from a Well

Follow these steps carefully—precision matters.

Step 1: Install the Check Valve (Near the Pump)

• Place a check valve on the well pump’s discharge line to prevent backflow into the well.
• This protects the pump and maintains prime.

Step 2: Run the Main Supply Line to the Pressure Tank

• Use ½” or ¾” PEX or copper pipe from the well head to the tank inlet.
• Keep the run as straight and short as possible to reduce friction loss.

Step 3: Mount the Pressure Tank Vertically

• Place the tank on a level, stable surface (concrete pad or sturdy platform).
• Leave 6–12 inches of clearance around it for airflow and maintenance.

Step 4: Pre-Charge the Tank

• Before connecting water, set the air pressure in the tank bladder:
  • Use an air compressor to charge to 2 PSI below the pump cut-in pressure.
  • Example: If your pressure switch is set to 40/60 PSI, pre-charge to 38 PSI.
• Check with a tire gauge—never guess.

Step 5: Connect the Plumbing

• Attach the main supply line to the tank’s inlet port (usually at the bottom).
• Install a tee fitting after the tank to split flow:
  • One branch to the pressure switch and gauge
  • The other to your house supply line

🔧 Critical Detail: Wrap all threaded connections with 3–5 wraps of Teflon tape clockwise to prevent leaks.

Step 6: Wire the Pressure Switch

• Mount the pressure switch near the tank.
• Connect it to the pump’s control circuit (follow manufacturer wiring diagram).
• Ensure the switch activates at your desired cut-in/cut-out pressures (standard is 40/60 PSI).

Step 7: Test the System

1. Open a faucet to purge air.
2. Turn power back on.
3. Listen for smooth pump cycling—should run 30–90 seconds per cycle.
4. Verify pressure gauge reads correctly and stabilizes.

Common Mistakes to Avoid

Maintenance Tips for Longevity

• Check air pressure every 6 months (with system depressurized).
• Inspect for leaks monthly at joints and valves.
• Flush sediment annually if you have hard water.
• Replace the tank if you notice waterlogging (tank feels heavy, pump cycles rapidly).

FAQ Section

Q1: Can I plumb a pressure tank myself, or do I need a plumber?

A: Many homeowners successfully install pressure tanks themselves if they’re comfortable with basic plumbing and electrical work. However, if your system involves deep wells, complex controls, or local code requirements, consult a licensed well contractor.

Q2: Where should the pressure tank be installed?

A: Install it indoors (in a basement or utility room) if possible to protect it from freezing. If outside, insulate it and use a weatherproof enclosure in cold climates.

Q3: What’s the difference between a bladder tank and a diaphragm tank?

A: Both separate air and water, but bladder tanks have a replaceable rubber bladder, while diaphragm tanks have a fixed membrane. Bladder tanks are more common in modern residential systems and easier to service.

Q4: Why is my pressure tank losing pressure quickly?

A: Likely causes:

• Air leak in the bladder or valve
• Waterlogged tank (bladder ruptured)
• Faulty pressure switch
  Test by draining the tank and checking air pressure with no water inside.

Q5: How often should I replace my pressure tank?

A: Most tanks last 10–15 years. Signs it’s time: frequent pump cycling, rust on the exterior, or inability to hold air pressure.

Q6: Can I use PEX pipe for the entire well-to-tank run?

A: Yes! PEX is freeze-resistant, corrosion-proof, and code-approved for potable water. Just ensure it’s rated for your system’s max pressure (usually 80–100 PSI).

Conclusion

Knowing how to plumb a pressure tank from a well empowers you to maintain a reliable, efficient water system while avoiding expensive repairs. With the right tools, proper sizing, and attention to detail, you’ll enjoy steady water pressure for years to come.

👉 Found this guide helpful? Share it with a fellow homeowner on Facebook, Pinterest, or Reddit! Your DIY success could inspire someone else to take control of their home’s water system—safely and confidently.

Remember: When in doubt, consult a certified well professional. Water systems involve electricity and pressure—safety always comes first.