Why Is My Pool Pump Humming but Not Running?
A pool pump that hums but does not run usually has a failed start capacitor, a jammed impeller, or seized motor bearings. Turn it off right away. A motor that hums without spinning overheats quickly and can burn out. With the power off at the breaker, you can check for a jammed impeller yourself. A capacitor or bearing problem is a repair job, and Top Dog Pool Supply repairs pumps and is a warranty station for most major brands.
What causes a pump to hum and not start?
- A bad start capacitor. The capacitor gives the motor the kick it needs to start. When it fails, the motor hums and does nothing. Heat shortens capacitor life, and Bakersfield summers are hard on them.
- A jammed impeller. A pebble, seed pod, or wad of debris can lock the impeller.
- Seized bearings. Bearings rust and lock up, often after a leaking shaft seal lets water into the motor, or after the pump sits unused.
- Low voltage or a wiring problem. A loose connection or the wrong voltage keeps the motor from starting.
- A failed motor. If the windings are burned, the motor needs to be replaced.
What can I check myself?
- Step 1: Turn the pump off at the switch or timer, then turn off the breaker.
- Step 2: Let the motor cool if it is hot.
- Step 3: Open the pump lid, pull the basket, and feel for debris in the opening behind the basket that leads to the impeller.
- Step 4: Check whether the motor shaft turns. On many pumps you can reach the end of the shaft at the back of the motor. If it will not turn by hand, the impeller is jammed or the bearings are seized.
- Step 5: If you cleared a jam, put the pump back together, fill the pump pot with water, turn the breaker on, and try it once.
- Step 6: If it still hums, turn it off and leave it off.
Should I repair or replace the pump?
A capacitor is a small repair. Bearings or a burned motor cost more, and if the pump is 8 to 10 years old or single-speed, replacing it often makes more sense. Most replacement pumps are now variable-speed. When you buy a Pentair IntelliPro3 VSF from Top Dog, installation in Bakersfield is free, and it comes with a three-year manufacturer warranty.
When should I call for help?
Call us if the pump still hums after you clear the impeller, if the breaker trips, if the motor is too hot to touch, or if you smell burning. You can bring the pump or motor to the store. If you'd rather have us come to you, a service visit starts with a $139 diagnostic fee. It covers our fuel and travel time, diagnosing your pool equipment, and a written work order for your approval. The fee doesn't cover any repairs.
How do I know if my pump capacitor is bad?
The motor hums but does not start, or starts slowly, and the shaft turns freely by hand with the power off. A swollen or leaking capacitor is another sign. Have a technician test and replace it.
Can I keep trying to start a humming pump?
No. Each try overheats the motor. Leave it off until the cause is fixed.
Why does my pump trip the breaker?
A shorted motor, water in the motor, or a wiring problem. Leave it off and have it checked.
How long should a pool pump last?
About 8 to 10 years. Heat, leaks, and running dry shorten that.
Don't cry, we can help
Bring the part, a photo, or the model number to Top Dog Pool Supply, and we'll help you figure out what it needs. We repair and install pool equipment and are an authorized service center for most major brands.
Visit us at 7440 District Blvd Suite B, Bakersfield, CA 93313, or call (661) 664-9000. We're open Monday to Friday 9 to 5, Saturday 9 to 4, and Sundays 10 to 4 from April through September.
Financing is available through GreenSky: 12 monthly payments on pool equipment, interest-free when paid in full within 12 months, subject to credit approval. Call (661) 664-9000 for details.