Quick answer
Turn off the pump at the breaker. Raise the water to mid-skimmer, clear the basket, open the valves and check the pump lid and o-ring. Fill the strainer with water and restart once. If it still will not hold prime, stop and call a technician; do not run it dry.
What you're seeing
- No water is moving from the returns.
- The pump basket stays partly empty or bubbles appear at the returns.
- The pump is hot, loud, humming or tripping the breaker.
- Pressure is low and the pool is not filtering.
What usually causes it
Cause 01
Water level is below the skimmer
The pump pulls air instead of water. This is the first thing to check, especially after a leak or a hot week.
Cause 02
Air leak on the suction side
A loose lid, dry o-ring, cracked union or failing valve can let air in before the pump.
Cause 03
Clogged basket or impeller
Leaves, hair and pine needles restrict flow. The impeller can also wrap with debris even when the basket looks clear.
Cause 04
Motor or electrical fault
A humming motor, tripped breaker or burning smell needs a licensed electrician, not another attempt to restart it.
How to fix it, in order
Work through these steps once, with the pump running and the filter clean. Do not stack a second chemical dose before the first has circulated and you have retested.
- 01
Cut the power first
Turn off the pump at the breaker before opening the lid, basket or any union.
- 02
Check the water level
Fill to the middle of the skimmer mouth. If it drops again quickly, investigate a leak before running the pump continuously.
- 03
Clear the suction path
Empty the basket, open the skimmer valve and check the impeller through the strainer opening. Remove debris carefully.
- 04
Restore the prime
Fill the strainer with water, lubricate a dry o-ring if needed, close the lid and start the pump once. Watch for a quick, steady prime.
- 05
Stop if it will not hold
Repeated dry starts damage the seal and motor. If the pump hums, trips the breaker or still pulls air, call a technician.
What not to do
- Never run a pump dry; the seal and motor can overheat quickly.
- Do not open the strainer lid while the pump has power.
- Do not keep resetting a breaker that trips; that is an electrical fault.
Keeping it from coming back
- Keep the water at mid-skimmer and the baskets clean.
- Inspect the pump lid o-ring and unions at the start of the season.
- Watch for air bubbles and address them before they become a prime problem.
- Drain and protect the pump before the first Ontario freeze.
When to stop and call a pro
Do not force it
Call a licensed technician if the breaker trips, the motor hums without spinning, there is a burning smell, the pump leaks at the seal, or it still will not prime after the basic checks. Electrical and motor work is not a DIY repair.
Compare local repair helpGeneral guidance for residential pools in Ontario. Chemical doses depend on pool volume and test results; follow the product label and keep gas, electrical and major shell work with licensed trades.