Your swimming pool pump must be primed in order to operate properly. When your pool pump is on but the pool water is not moving, the pump has "lost its prime". This means that air has entered the pump. Be sure to determine why the pool pump has air in it, instead of water, before you prime the pump again. Follow these steps carefully, to ensure you have covered every contingency. The safety of swimmers using your pool depends on the pump working in optimum condition.
Step 1- Figure Out How the Air Got In
Air is often present in the pump the first time you start it up in early summer, especially if you "winterized" your pool by disassembling the pump. Be sure you have reinserted and resealed all the parts you took out of the pool pump. Check that the water level in the pool is as high as possible and that it is flowing into the skimmer inlets. Inspect and clear any clogs and debris in the skimmer and the primary drain. Remove decaying leaves and hair from the pump strainer basket and the impeller. After these possibilities have been eliminated, try to prime the pump manually.
Step 2- Prepare to Prime the Pump
Shut off all the pool support equipment, including the pump, filter unit, and pool heater. Open the valve marked "Air Relief" at the top of the pool pump. Close all the skimmer inlets, and then open the primary drain valve completely. Check that the pump basket is full of water. If not, add as much as necessary by garden hose or bucket. Examine the pool pump lid and its O-ring seal, in the underside of the lid, for wear, cracking or other damage. Replace the O-ring if it shows any of these problems. Do not lubricate the O-ring or any other gaskets or seals. This will cause particles to stick to them, preventing an effective seal. Secure the pump lid again, fastening the screws to "hand tightness". Avoid over-tightening, as this strains the flexible seals. Set the valve on top of the pool filter to the filter position.
Step 3- Prime the Pump
Activate the pump. Run it for 2 to 3 minutes, but no more than 5 minutes. If the pool water flow does not begin after 5 minutes, shut the pump off and try again. Pool pumps tend to be water-cooled, so running yours "hot" could damage the pool pump seal, impeller and motor. When the pool pump is circulating water effectively again, open the skimmer inlets one at a time, checking that the pump does not lose suction again. Once all the skimmer inlets are open, close the pump's "Air Relief" valve, and restart the swimming pool filter unit.
As a pool owner, become familiar with the machines that help your pool operate and keep the water safe to swim in. The more thoroughly you understand them and learn to maintain them yourself, the better your pool's support systems will function.