Has your well pump lost pressure? This happens more often than you’d think. Don’t worry, the fix is simple—you just need to prime the pump to restore flow and pressure.
What Does It Mean to Prime a Well Pump?
When a well pump loses its prime, the motor may still run, but no water gets delivered. Priming is what allows the pump to function correctly.
Priming a well water pump involves filling the pump and suction line with water to remove any trapped air. Air interrupts the vacuum needed for the pump to pull water from the well. Without a vacuum, no water will flow.
This process is most commonly required for jet pumps, which sit above ground and rely on suction, as opposed to submersible pumps that operate underwater and push water upward.
Signs Your Well Pump Needs Priming
A well system doesn’t always stop suddenly. Often, warning signs appear as the problem gradually worsens. Here’s what to watch for:
- Low water pressure: Faucets produce a weak stream that never improves.
- Inconsistent flow: Water comes out in short bursts or varies in intensity.
- The pump won’t start the water flowing: The motor activates, but your sinks and showers stay dry.
- Gurgling sounds: Air moving through the plumbing creates unusual noises.
- Frequent cycling: The pump switches on and off repeatedly but never builds proper pressure.
Common Causes of Lost Prime in Well Pumps
How can a well pump lose its prime? Here are some of the most common culprits:
- Air leaks in the suction line: Loose fittings or cracked pipes allow air to enter the system.
- Foot valve failure: The one-way valve at the bottom of the suction line fails to prevent water from flowing backward.
- Low water level in the well: Seasonal shifts or drought conditions reduce the available water, allowing air to enter the line.
- Drainage after maintenance: If the system was serviced or shut down, water may have drained from the pump and piping.
- Cracks in the pump housing: Even tiny fractures can create a sufficient gap to allow air to enter.
How to Prime a Well Pump
Priming a well pump is a hands-on process. Follow the steps in this guide to prime your jet pump and restore water flow safely.
Step 1: Turn Off Power to the Pump
Safety first! Switch off the power to work on the system without the risk of electric shock or accidental activation. Locate the breaker that controls the pump and turn it off before proceeding.
Step 2: Locate the Priming Plug
The priming plug (usually a screw‑type cap or plug) is typically located on the volute plate or casing, where you can easily remove it. Do so now to access the internal chamber.
Step 3: Fill the Pump with Clean Water
Pour water through the priming port until the pump housing is full. A garden hose works well for this step, but a clean bucket can be used if needed. Have a clean rag or towel nearby in case of overflow.
Take your time and make sure water fills the housing completely. You’ll know you’ve added enough water when it reaches the level of the port opening. If air bubbles rise up while filling, let them escape. This is the trapped air you’re trying to eliminate.
Step 4: Replace the Plug and Restore Power
Once the housing is full, replace the priming plug and secure it to form a watertight seal. Next, restore the power at the breaker panel. Return to the pump and observe it as it starts.
If you’ve primed it correctly, the pump should begin to pull water, and pressure should start to build. Open a faucet in the house, and before long, it should stop sputtering and begin flowing normally.
Step 5: Repeat If Necessary
Sometimes, one attempt isn’t enough. If the pump still won’t start moving water, shut off the power again and repeat the process. Air can remain trapped deeper in the suction line, especially if it runs long distances or slopes upward. Attempting a few rounds of priming usually resolves the issue.
Safety disclaimer: If you’ve tried several times and the pump still doesn’t work, there may be a mechanical or system-level issue. A broken foot valve, suction leak, or internal failure may require professional diagnosis and repair.
Preventing Future Well Pump Problems
A little maintenance goes a long way when preventing your well pump from losing pressure. Here’s how to keep your system operating smoothly:
- Inspect suction lines and fittings regularly, and tighten seals as needed.
- Replace aging check valves or foot valves before they fail.
- Avoid running the pump dry. Install a low-pressure cutoff switch if necessary.
- Clean sediment filters to avoid backpressure on the pump.
- Schedule annual well inspections to catch wear and tear early.
Professional Well Pump Services from FlowCore
If you need help priming your well water pump or suspect it needs a more in-depth repair, turn to FlowCare. We have supported North Texas homeowners with well pump services since 2006. Our team combines advanced diagnostics with real-world experience to resolve issues like lost pressure, dry pumps, and failed priming. We also design, drill, and maintain well systems across the Dallas-Fort Worth area.
Reach out today to ask questions or schedule well pump services.
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