The pump is a vital component to your swimming pool. It keeps water flowing through the filter so that your pool isn't littered with leaves or other debris. It also maintains a circulating current in the water, reducing your risk of nuisance algae. There are several reasons why your pump may randomly shut off—a behavior known as "pump tripping." Most commonly, your pump may be operating at the wrong voltage, overheating, or simply failing to compete with your neighborhood's electrical needs.
One of the most common causes of a pump tripping is incorrect voltages. The pump requires a motor to function, and that motor requires electricity. Most pool pump motors are designed to run off 115 or 230 volts. If your pool was recently installed or if your pump was recently replaced, it may be wired incorrectly. This scenario is the most likely if your pump consistently trips just five to ten seconds after turning on. A bad capacitor may also be to blame. Capacitors regulate the amount of electricity the pump receives and can go bad with age. Loose wires can also reduce the amount of voltage into the pump. Have a licensed electrician inspect the pump immediately, especially if you are unfamiliar with pool pump wiring.
The pump uses a spinning impeller to suck water through the pool's filter. If the impeller gets stuck, the pump motor will hum and then may shut itself off. Any sort of debris can get wedged in the impeller and hinder its movement, including rocks, leaves, dead animals or articles of clothing.
Freeing the impeller requires taking the pump apart. If you're not comfortable doing this, call in a professional.
A lack of flowing water can give the illusion that the pump has shut off even when it hasn't. If your pump is running but is not actually moving any water, it may need to be primed. Priming is when water is allowed to flow through the pump and the pool's filter. Check the water level in your pool.
For safety reasons, many pool pumps are designed to shut off automatically if they begin to overheat. The mechanisms that perform this task are known as thermal overload switches. If your pump continues to shut off, it could mean that the thermal overload switches are going bad. It is also possible that your pump is overheating, in which case you'll need a technician to determine why and solve the problem. You should troubleshoot an overheating pump yourself only if you are very familiar with the device.
High Energy Demand
On extremely hot days, your pool pump may shut off because it simply cannot pull enough electricity from the grid. Power drops from your local supplier may occur when a large number of people are all running air conditioning units, swimming pool pumps, and other devices at the same time. Your local power company should be able to verify a power drop in your area. If this is the problem, you will simply have to wait to turn on your pump until full power is restored.