Why does my well pump lose prime?

A well pump loses prime when air gets into the suction side, water level drops below the intake, or there is a leak, blockage, or failed component in the system.

Common reasons a well pump loses prime

When a pump loses prime, it cannot move water because the pump casing and suction line are no longer full of water. In a shallow well system, that usually means the pump is pulling air somewhere or the well water level has fallen out of reach. In deeper systems, the problem is often tied to a check valve, foot valve, drop pipe, pressure tank issue, or pump wear.

In Central Florida, we also see seasonal water-table changes, aging equipment, and lightning-related damage that can make the problem show up suddenly. If your water stopped after a storm, the issue may be more than a simple loss of prime.

Signs the pump has lost prime

A few common symptoms point to a priming problem:

• The pump runs, but no water comes out
• Air spits from faucets before the flow stops
• The pump turns on and off repeatedly
• The pressure gauge drops to zero
• You hear the pump running louder than normal
• The system will work again after adding water, then fail later

If you are dealing with a drinking water well or a mobile-home-park well that is down, call us. Dunham Well Drilling handles well and pump problems across Polk County and Central Florida, and our Pump Repair & Installation service covers the parts that commonly fail in these systems.

What usually causes a prime problem

A pump loses prime for a reason. The fix depends on whether the issue is on the suction side, in the well, or in the pump itself.

Air leaks on the suction side

The most common cause is air getting into the line between the well and the pump. Even a small leak can break prime over time. On shallow well systems, that can happen at fittings, unions, pipe joints, cracked plumbing, or a worn seal.

If the pump has to be reprimed often, don’t assume the water table is the only issue. We regularly find small air leaks that are easy to miss without checking the whole system.

Check valve or foot valve failure

A failed check valve or foot valve lets water drain back out of the line after the pump shuts off. Once the line empties, the pump has to start over, and sometimes it cannot recover prime at all.

This is one of the first things we look at during pump service. A bad valve can look like a pump problem, but the real issue may be deeper in the well plumbing.

Low water level in the well

If the water level drops below the intake, the pump will pull air instead of water. That can happen during dry periods, heavy irrigation use, or if the well is undersized for the demand.

This is where a proper well evaluation matters. Dunham does Water Well Drilling and Shallow (2-Inch) Irrigation Wells for properties that need dependable water for irrigation and other uses. We also know which Polk County areas support reliable shallow wells and where deeper wells make more sense.

Pump wear or mechanical damage

An older pump can lose efficiency or develop internal wear that keeps it from holding prime. That includes worn seals, damaged impellers, or motor issues. In some cases, the pump needs repair rather than replacement.

Dunham’s Pump Repair & Installation service includes residential pumps, irrigation pumps, turbine pumps, industrial pumps, centrifugal pumps, and pressure tanks. We also have a full-line machine shop on-site, so pumps and turbines can be rebuilt in-house when that is the right fix.

What to check before you call

If you want to narrow down the problem before a service call, there are a few safe observations you can make.

• Look at the pressure gauge
• Listen for air in the water lines
• Check whether the pump loses prime after sitting overnight
• Note whether the problem started after a storm or power issue
• See whether the system is affecting one tap or the whole property

Do not open electrical components, pressure tank connections, or well equipment you are not trained to handle. If the pump is tied to electrical service or pressure controls, it is time to call a professional.

When the problem may be lightning-related

In Polk County, lightning damage is a common reason well systems fail. A strike can damage the pump, motor, pressure switch, or control equipment, and sometimes the system looks like it simply lost prime when the real problem is electrical.

If the trouble started after a storm, our Lightning Damage Repair service is designed for that situation. We can help with pump and motor repair, irrigation system electrical repair, pressure-switch and control replacement, and well casing damage assessment.

How Dunham finds and fixes the problem

We don’t guess at a prime issue. We look at the full system: the well, pump, controls, pressure tank, and water conditions. That matters because the same symptom can come from different causes.

If water quality is part of the problem, our Water Filtration & Treatment service can help identify what is actually in your water. We do on-site water testing and install treatment systems for hard water, smelly water, iron staining, and hydrogen sulfide odors.

For customers with irrigation systems, we also offer Irrigation Repair & Installation. That is useful when the loss of prime is tied to irrigation demand, pump issues, or a hard-to-find part that needs to be sourced quickly.

We’ve been serving Winter Haven and Polk County since 1950, and that experience matters when you are trying to diagnose a well system that keeps going down for the same reason. We are also a Florida Ground Water Association member and a licensed water well drilling contractor.

Call Dunham when your well pump keeps losing prime

If your well pump keeps losing prime, calls are worth making as soon as the system starts acting up, especially if you have no water, weak pressure, or a drinking water well or mobile-home-park well that is down. Call Dunham Well Drilling at (863) 965-2881 for help; we offer a 24/7 answering service, return calls within 48 hours, and bring 76 years of Central Florida well experience plus an on-site machine shop to the job.