Why Won’t My Pool Pump Prime?
A pool pump that won't prime is almost always pulling in air instead of water. The usual causes are low water level, a clogged skimmer or pump basket, a dry or cracked pump lid O-ring, or a closed valve, and you can check all of them in about 15 minutes. If you've checked those and the pump still won't catch water, or it hums without spinning, turn it off to protect the motor. Then call Top Dog Pool Supply at (661) 664-9000.
What are the 7 checks for a pump that won't prime?
- Step 1: Water level. It should reach the middle of the skimmer opening. On a hot, windy Bakersfield day, a pool can lose a lot of water to evaporation, and once the level drops below the skimmer, the pump sucks air.
- Step 2: Skimmer basket and door. Empty the basket and make sure the floating door (weir) isn't stuck closed.
- Step 3: Pump basket. Empty it and check that it isn't cracked. Leaves packed in the basket starve the pump.
- Step 4: Lid O-ring. Wipe it clean, check for flat spots or cracks, and coat it lightly with a silicone-based pool lubricant. Don't use petroleum jelly, because it swells rubber. A worn O-ring is the most common air leak, and we keep replacements in stock.
- Step 5: Fill the pump pot with water. Use a hose or bucket to fill the pump housing to the top, close the lid snugly, then turn the pump on.
- Step 6: Valves. Make sure the suction valves (skimmer and main drain) and return valves are open. A valve turned the wrong way after cleaning is a common culprit.
- Step 7: Look for air leaks. A steady stream of bubbles in the pump basket means air is getting in somewhere on the suction side. Check drain plugs, the lid, the unions in front of the pump, and any cracked fittings.
Why does my pump lose prime overnight?
If it primes but loses water when it shuts off, there's usually a small air leak on the suction side, often the lid O-ring, a pump union, or a cracked fitting. A pool that loses water to evaporation during the day can also drop below the skimmer overnight.
When is a pump problem beyond DIY?
- The motor hums but doesn't spin. That's usually a failed capacitor or seized bearings.
- It screeches or grinds, or the motor is too hot to touch.
- Water is leaking from between the pump and the motor. That means the shaft seal has failed.
- The breaker trips.
- It still won't prime after all seven checks. The impeller may be clogged or there may be a hidden suction leak.
Should I repair or replace my pool pump?
If your pump is older and single-speed, replacing it often makes more sense than repairing it. Federal efficiency rules that took effect in 2021 mean most replacement pool pumps are now variable-speed. Running slower for longer is also how you get the most from a pump through a long Bakersfield swim season. When you buy a Pentair IntelliPro3 VSF from Top Dog, installation in Bakersfield is free, and it comes with a three-year manufacturer warranty. Pentair rates it for up to 90% energy savings compared with single-speed pumps. Ask us about the IntelliPro3 offer.
How long should it take a pool pump to prime?
Most pumps catch water within a couple of minutes once the pump pot is filled with water and the lid is sealed. If nothing is moving after about 5 minutes, shut it off so it doesn’t run dry, and check water level, baskets, the lid O-ring, and valves.
Can a pool pump run without water?
Only briefly. Running dry for more than a few minutes can overheat and melt the shaft seal and pump parts. Always fill the pump pot before restarting.
Why are there bubbles in my pump basket?
Bubbles mean air is getting into the suction side: low water level, a worn lid O-ring, a loose drain plug, or a cracked fitting before the pump.
Why does my pump hum but not run?
A humming pump that won’t spin usually has a failed start capacitor or seized bearings. Turn it off right away to avoid burning out the motor, and have it checked.
Don't cry, we can help
Bring a water sample to Top Dog Pool Supply. Local pool owners get a free water test on our Taylor Xpress Flex system, and we'll tell you what to add, and how much, for your pool's size.
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.