If you find that your water system is losing pressure or failing to cycle, you can perform basic flojet pump troubleshooting by checking the power supply, the intake lines, and the filter screen. Most pump failures stem from air leaks in the suction line or a clogged inlet filter rather than an internal mechanical breakdown. If the pump runs continuously without building pressure, you likely have an air leak between the water tank and the pump head.
Troubleshooting common flojet pump failures
When your pump fails to operate, the most common cause is a lack of power or a tripped thermal breaker. These units rely on a steady flow of electricity to engage the internal motor. If the motor doesn’t hum when you open a faucet, check the fuse or the circuit breaker first. A blown fuse often indicates a motor that’s drawing too much current due to internal wear.
Another frequent issue is debris entering the pump head. Even small particles of sediment can block the check valves, preventing the pump from holding pressure. When these valves can’t seat properly, water flows backward into the tank, causing the pump to cycle on and off rapidly. This behavior is called “short cycling” and can lead to early motor failure if not addressed quickly.
Finally, check the suction side for air leaks. If the hose clamps are loose or the inlet fittings have cracks, the pump will pull in air instead of water. Because air is compressible, the pump can’t reach the pressure threshold required to trigger the internal pressure switch. You can verify this by checking the Flojet product installation manuals for the specific pressure settings of your model, which vary based on the pump’s intended flow rate and voltage.
Safety: Inside a mains-powered machine, the parts behind the outer cover can hold a dangerous electrical charge even after it has been unplugged — that’s why they sit behind a cover. Opening the housing, or testing or replacing anything behind it, is a job for a qualified technician, never a home repair.
Inspecting electrical supply and connections
If your pump is completely silent, the issue is almost always electrical. Start by verifying that the battery or power source provides the correct voltage for your specific unit. If you’re using a 12V system, ensure the battery charge hasn’t dropped below 11V, as the motor may lack the torque to start.
Check the wiring terminals for signs of corrosion or loose connections. A loose wire creates high resistance, which generates heat and can melt the plastic connectors near the motor. If the wires feel hot to the touch while the pump is trying to run, shut off the power immediately to prevent a fire.
This section isn’t for users who want to perform internal motor repairs or bypass the pressure switch. If your electrical system is sound but the motor still fails to turn, the internal brushes are likely worn out. In such cases, you should replace the entire pump assembly rather than attempting to open the sealed housing. Attempting to pry open a sealed motor housing usually breaks the waterproof gasket, which guarantees a short circuit within days of reinstallation.
Cleaning the inlet filter and intake
A clogged inlet filter is a common reason for low water flow. Most pumps have a clear plastic strainer located on the suction side before the water enters the pump head. Over time, sediment and mineral deposits build up inside this mesh, restricting the volume of water the pump can draw.
To clean the filter, turn off the water supply and unscrew the clear cap on the strainer. Remove the mesh screen and rinse it under clean, running water to clear any trapped debris.
Avoid using sharp tools to scrape the screen, as this can create holes that allow grit to pass into the pump head. If the mesh remains discolored after rinsing, soak it in a solution of equal parts white vinegar and water for thirty minutes to dissolve stubborn mineral scale.
If the screen is clear but the flow remains weak, check the intake hose for kinks or collapses. A vacuum can cause a soft hose to pinch shut, which starves the pump of water. This is a common mistake for users who install flexible tubing without proper reinforcement, costing them efficiency and potentially burning out the pump motor due to dry running.
If your hose collapses under suction, replace it with a wire-reinforced suction hose. This rigid construction prevents the tube from flattening while maintaining the necessary flow rate for your specific pump model.
Fixing persistent pressure switch issues
The pressure switch is the small component that tells the pump when to turn on and off. If the pump stays on even when all faucets are closed, the switch may be stuck or out of calibration. This often happens if the system is frequently exposed to high pressure or if the water contains high levels of calcium.
Before you consider a replacement, ensure that all faucets and valves are fully closed. Even a slow drip in a showerhead or a leaking toilet valve will prevent the pressure from building enough to trip the switch. Check your water meter; if the dial moves while everything is off, you have a leak, not a switch failure.
If you have confirmed there are no leaks in your plumbing, the internal diaphragm of the switch may be damaged. A common mistake is attempting to adjust the spring tension screw to compensate for a failing diaphragm. This rarely works and often leads to the pump cycling rapidly, which can burn out the motor windings within weeks.
This fix is for users who have verified the rest of their plumbing is airtight. If the pump continues to run despite having no leaks and a clear filter, the pressure switch has reached the end of its functional life.
At this point, the most cost-effective path is to replace the switch assembly or the pump unit, as internal calibration requires specialized equipment not available to the average home user. If the contacts show visible pitting or black carbon buildup, don’t attempt to clean them; replace the entire unit immediately.
Common mistakes to avoid
Running the pump dry is the most common fatal error. Operating the unit without water causes internal seals to overheat and fail within minutes. If you hear the pitch of the motor rise significantly, cut the power immediately to prevent permanent damage.
Ignoring a cycling pump is equally destructive. If the unit kicks on and off every few seconds, you likely have a pressure leak or a faulty check valve. This rapid switching ruins the motor brushes and drains your battery in under an hour.
Using undersized wiring creates a hidden bottleneck. Thin wires cause voltage drops that prevent the motor from reaching rated speed and pressure. Always match your gauge to the manufacturer’s length requirements.
Finally, avoid over-tightening plastic fittings. These ports crack easily under pressure, creating microscopic air leaks that are nearly impossible to diagnose. Tighten fittings by hand, adding only a quarter-turn with a wrench if absolutely necessary.
Maintaining system integrity
You can prevent many of these issues by performing a simple check of your water system once every three months. The goal is to ensure the pump isn’t working harder than necessary to move water through your home.
| If you’re doing this | Do this instead | Why |
|---|---|---|
| Using thin, flexible tubing | Use reinforced, rigid piping | Prevents hose collapse and air leaks |
| Ignoring a slow drip | Fix the leaking faucet | Stops the pump from cycling constantly |
| Forgetting the strainer | Inspect the filter monthly | Keeps debris away from the valves |
| Running on low battery | Keep voltage above 11V | Protects the motor from stalling |
Most owners mistake a buzzing sound for normal operation. If you hear a constant hum while no taps are open, your system is likely fighting a hidden pressure leak. This oversight increases electricity consumption and significantly shortens the pump’s lifespan.
To diagnose the source, close all valves and watch the pressure gauge for sixty seconds. If the needle drops, you have a leak. If the needle remains steady, the issue is likely a failing check valve. Always prioritize sealing the leak before replacing the pump.
Frequently asked questions
Why does my pump turn on when I am not using water?
Your pump is likely reacting to a small leak somewhere in your plumbing system. Even a tiny, invisible leak in a toilet valve or a faucet will cause the pressure in the lines to drop. When the pressure falls below the factory set point, the pump activates to restore it. Check every fixture in your home for moisture or drips, as these are the most common causes of phantom cycling.
How long should a pump last?
A standard pump typically lasts for a variable period, though this depends entirely on the frequency of use and the quality of the water. Units used in systems with high sediment or those that run continuously will fail much sooner than those in clean, low-demand systems. If your pump is frequently cycling or running dry, you can expect its lifespan to be cut by at least half.
Is it safe to repair the pump myself?
It’s safe to perform external maintenance like cleaning the filter or checking electrical connections, but you should never open the motor housing. Internal repairs require specific tools and technical training to avoid damaging the seals or the motor windings. If the problem is internal, you risk voiding your warranty or causing an electrical hazard by attempting to disassemble the pump components yourself.
What happens if I ignore the air in my lines?
If you ignore air in your lines, the pump will struggle to build the pressure needed to trigger its automatic shut-off switch. This causes the motor to run continuously, which generates excessive heat and wears out the internal diaphragm. Over time, the motor will overheat and fail completely, requiring you to replace the entire unit rather than just bleeding the air out of the system.
How do I stop the pump from vibrating?
You can stop the vibration by mounting the pump on rubber feet or using flexible hoses to connect it to the plumbing. Most vibration comes from the motor’s movement transferring through rigid pipes into the wall or floor of your home. By adding a small amount of “give” to the connection points, you isolate the motor and significantly reduce the noise it makes during normal operation.
Conclusion
If you’re still having trouble after checking these common points, contact a licensed plumber or the manufacturer’s customer support for your specific model. They can help you determine if the issue is a simple fix or if the unit has reached the end of its functional life.
