TITLE: Why Are Bubbles Coming Out of My Pool Return Jets?
META DESCRIPTION: Seeing bubbles coming from your pool return jets? Learn what causes air in pool plumbing, how to check for suction leaks and when to call for repairs.
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Why Are Bubbles Coming Out of My Pool Return Jets?
You walk outside and notice a steady stream of bubbles coming from the return jets in your swimming pool.
At first, it doesn’t seem like a big problem. The pump is running, water is circulating and the pool looks relatively normal.
But the bubbles keep coming.
Persistent bubbles from pool return jets often mean air is entering the circulation system, although some equipment intentionally introduces air into the water. A low water level, suction-side plumbing leak, loose pump lid or problem with the pump’s water supply can allow air to move through the system.
In Lake Havasu City, where evaporation can lower pool water levels quickly, checking the water level is a sensible first step.
Are Bubbles Coming From Pool Returns Normal?
A few bubbles immediately after starting the pump may be normal, especially after the system has been opened for maintenance.
Air that entered during filter cleaning or pump basket maintenance may need time to move through the plumbing.
However, continuous streams of bubbles from standard return jets deserve investigation.
There are also exceptions.
Some spas and water features intentionally introduce air. Certain pool systems use ozone generators or other equipment that can create visible bubbles during normal operation.
Before diagnosing a leak, identify whether your system includes equipment designed to introduce air.
1. Check the Pool Water Level
Start with the simplest possibility.
If the pool water level falls too low, the skimmer may begin pulling air along with water.
That air travels through the pump and circulation system before appearing at the return jets.
Depending on the skimmer design, the water level is commonly maintained around the middle of the skimmer opening, but you should follow your pool builder’s or equipment manufacturer’s recommendations.
If the water is below the proper operating level, correct it before continuing to run the system.
Lake Havasu’s hot, dry climate makes evaporation a recurring maintenance concern. EverClear explains local water-loss conditions in its article on pool evaporation and distinguishing normal water loss from leaks.
2. Inspect the Skimmer Basket and Weir Door
The skimmer helps remove floating debris from the pool surface.
If the basket is heavily clogged, water flow into the system may be restricted.
The skimmer’s floating weir door can also become stuck or fail to move properly.
Under certain conditions, restricted water flow can contribute to the skimmer drawing air.
With the system safely shut down as directed by the manufacturer, inspect and clean accessible skimmer components.
Make sure the weir door moves freely and isn’t trapped in an incorrect position.
3. Check the Pool Pump Lid and O-Ring
The pump lid is another common place to investigate.
Most residential pool pumps have a clear lid covering the strainer basket.
A damaged lid seal, improperly seated O-ring or loose lid may allow air to enter the pump while it’s operating.
Sometimes the problem appears shortly after someone opens the basket to remove debris.
The lid may not have been seated correctly, or the seal may have become dirty or displaced.
Turn the pump off before inspecting the lid. Follow the manufacturer’s instructions for safely relieving pressure and opening the equipment.
Never open a pressurized pool system.
Inspect the seal for damage, debris or incorrect placement. Replace damaged parts with components specified for your pump.
4. Could There Be a Leak in the Suction Plumbing?
Yes.
The suction side of the circulation system includes the plumbing that carries water from the pool toward the pump.
When the pump operates, these lines are under negative pressure relative to the surrounding air.
A small opening may allow air to enter even when water isn’t visibly leaking out.
Possible problem areas include:
- Pump inlet connections
- Threaded plumbing fittings
- Valve stems and seals
- Pipe joints
- Damaged suction plumbing
- Equipment connections that have deteriorated over time
This explains why a pool can have an air leak without an obvious puddle around the equipment pad.
EverClear provides pool equipment and plumbing repair services throughout Lake Havasu City and Mohave County.
5. Look at the Pump Basket While the System Runs
If your pump has a transparent strainer lid, you may be able to observe the water inside without opening the equipment.
Many properly primed pumps operate with a basket chamber that appears mostly full of water.
A persistent large air pocket or substantial turbulence may indicate that air is entering the system or that the pump isn’t receiving an adequate water supply.
However, the appearance of the basket varies by pump model and operating conditions.
Use it as one clue rather than a final diagnosis.
6. Can a Dirty Pool Filter Cause Bubbles?
A dirty filter generally creates a restriction on the pressure side of a typical pool pump, not an opening where air enters.
Therefore, a dirty filter alone isn’t usually the direct cause of persistent air bubbles entering through the return jets.
It can affect overall circulation performance, and pressure readings may help identify separate flow problems.
If bubbles are present, inspect likely suction-side causes rather than assuming that cleaning the filter will solve everything.
7. Could the Pool Pump Be Losing Prime?
Yes.
When a pump loses prime, it no longer maintains the water-filled condition needed to circulate water properly.
Air entering through the suction side can contribute to this problem.
You may notice:
- A pump basket that doesn’t fill properly
- Reduced water flow from the returns
- Unusual pump noise
- Difficulty restarting after the pump shuts off
- Persistent bubbles in the return water
These symptoms can have several causes, so don’t assume a new pump is required.
If the pump cannot maintain proper prime, shut it down and arrange service rather than allowing it to run without adequate water.
Why Are the Bubbles Worse After Cleaning the Pool?
Sometimes a suction-side connection is disturbed during cleaning or maintenance.
For example, connecting or removing a suction cleaner hose may introduce air into the system.
Opening the pump basket can also introduce air that must be cleared after restarting.
Brief bubbles following maintenance may be expected.
If the bubbles continue, check that accessible connections were restored correctly and that the pump is operating normally.
Can Arizona Heat Affect Pool Plumbing Connections?
Pool equipment in Lake Havasu operates through extreme temperatures and prolonged sun exposure.
Over time, seals, plastic components and other equipment parts can deteriorate from age, operating conditions and environmental exposure.
Heat alone doesn’t prove why a particular fitting or O-ring failed, but damaged or aged components should be considered when investigating a persistent air leak.
Routine pool service and maintenance can help identify developing circulation and equipment problems before they become larger repairs.
Is It Safe to Swim When Bubbles Are Coming From the Returns?
Small bubbles by themselves don’t necessarily make pool water unsafe.
However, an underlying circulation problem can interfere with filtration and sanitizer distribution.
If the pump isn’t operating correctly, water circulation is significantly reduced or water chemistry cannot be maintained within appropriate limits, avoid swimming until the problem is corrected.
Also, never use a pool when electrical equipment is damaged or there’s reason to suspect an electrical hazard.
For guidance on maintaining healthy swimming pool water, consult the CDC’s home pool and hot tub water treatment recommendations.
When Should You Call for Pool Plumbing Repairs?
Arrange professional service if:
- Bubbles continue after the water level and accessible components have been checked
- The pump repeatedly loses prime
- Water flow is noticeably weaker than normal
- Air appears to enter through equipment connections
- The pump makes unusual noises
- You suspect a leak in buried or inaccessible plumbing
Locating suction leaks can require specialized diagnostic methods.
Attempting to seal random fittings without identifying the actual problem can waste time and leave the underlying issue unresolved.
Frequently Asked Questions
Why are bubbles coming out of my pool return jets?
Persistent bubbles often indicate that air is entering the circulation system. Common causes include low pool water, skimmer problems, damaged pump lid seals and suction-side plumbing leaks. Some specialized equipment intentionally introduces air.
Can a low pool water level cause bubbles?
Yes. If the skimmer begins drawing air because the water level is too low, that air can travel through the pump and appear at the return jets.
Why are there bubbles in my pool after the pump starts?
A short burst of bubbles may occur as trapped air clears after startup or maintenance. Continuous bubbles require further investigation unless the system is designed to introduce air.
Can a suction leak exist without losing pool water?
Yes. Because suction plumbing operates under negative pressure while the pump runs, a small opening may draw air inward without producing an obvious external water leak.
Will replacing my pool pump fix the bubbles?
Not necessarily. The problem may involve the pump lid seal, valve connections, water level or plumbing. Diagnose the source before replacing equipment.
Stop the Air Before It Becomes a Bigger Circulation Problem
Persistent bubbles from your pool return jets are worth investigating, especially when accompanied by weak circulation or difficulty keeping the pump primed.
Start with the water level, skimmer and accessible pump components. If the problem continues, have the suction plumbing and equipment evaluated.
EverClear Pool Service has served Lake Havasu City and Mohave County since 2005, providing pool pump, plumbing and equipment repairs along with regular pool maintenance.
If your pool is drawing air, losing prime or experiencing circulation problems, contact EverClear Pool Service or call (928) 453-5819 to schedule an equipment evaluation.