Skimming & Debris /
What Causes a Pool Skimmer to Suck Air Instead of Water?
A skimmer that pulls air usually points to low water, clogged baskets, a suction-side leak, or a valve issue. Start with safe checks before chasing hidden faults.
Archive date: this article was written for PoolSkimmer on Oct 7, 2026 and given the earlier archive date of Sep 16, 2026 so the blog reads as an organized archive. It was not published on that date.
The Cause of an Air-Pulling Skimmer
The job of a pool skimmer is to take surface water and feed it to the circulation system. When it begins to pull air, you will see the consequences: bubbles in the return jets, a churning basket, or even the pump losing its prime. In most cases, this points to a restriction or a minor leak on the suction side.
It is not something to put up with. A skimmer that does not work properly can leave debris behind, put undue strain on the filter and compromise circulation. Should the pump become uncharacteristically loud, lose prime with some regularity, or if there is any question of an electrical issue, the pool should be taken out of service and a professional called in.
Some Safe Preliminary Checks
Before going after leaks, rule out the simple things. Turn the pump off and consult the equipment manual before you open the skimmer basket or handle any of its components.
Look at the following:
- Water level: An opening that is not covered by water will draw in air.
- The baskets: Debris in the skimmer or a clogged pump basket will impede flow and reduce suction.
- Weir door: Make sure it is present and not stuck so the surface water can get in.
- Filter: If it is in poor condition, system flow will be affected.
Put on appropriate PPE for any inspection or cleaning. If the pool is running low, bring the level back to normal and see if that resolves it.
Dealing with Persistent Air
Assuming the baskets are clean and the water is at the right height, a leak on the suction side is the probable culprit. Because of the vacuum created when the pump is on, these do not always manifest as an outward drip. You might notice hissing from the pump lid, air in the strainer pot, or the pump failing to hold its prime once shut down.
Examine the pump lid for cracks, check the O-rings and unions for wear, and look over the valve stems and PVC fittings. The skimmer line or underground plumbing could also be at fault. Leave any motor components or electrical work well alone.
Valves, Blockages and the Elements
Make sure your valves are set correctly. If the skimmer is being starved because another line (like the bottom drain) is open too wide, or if a valve is only partially closed, the skimmer may start to pull air, particularly with changes in pump speed.
Then there are obstructions to consider, such as a clog in the skimmer throat or pipe, a problem with the impeller, or a check valve that has gone bad. A collapsed suction pipe underground is another possibility. High winds or a lot of activity in the pool can also upset the water level and skimming; in that event, let things settle and top off the pool before retesting. Under no circumstances should one put a hand into an opening where there is active suction.
Time to Call in an Expert
If you have done the basic checks and the skimmer is still drawing air, or if you are seeing a pattern of returning bubbles, a noisy or hot pump, or suspect a seal has failed, contact a qualified pool technician. They have the means to pressure-test the line and inspect seals without risk.
For your own safety, do not swim in cloudy water or if you have reason to believe there is an electrical fault in the vicinity of the equipment. And be sure to adhere to all manufacturer instructions and chemical labels when carrying out maintenance.