Why is My Pool Pump Sucking Air?

A clear, sparkling pool is a delight during the hot summer months — and a properly functioning pool pump is essential to maintaining the water's cleanliness and clarity. 

However, if you notice your pool pump is sucking in air, this can be a major cause of stress and concern.  

In this article, we explore the signs that your pool pump is sucking in air, the various causes behind the issue, how to find a pool pump air leak, and how to properly resolve the problem.

Air in the pool pump can lead to various problems, including reduced circulation, increased energy consumption, and potential damage to your equipment. Read on to discover how to keep your pool pump in great working condition during the swimming season. 

Signs My Pool Pump is Sucking-In Air

Before diving into the causes and solutions, it's essential to recognize the signs that indicate your pool pump is drawing in air. Identifying these warning signs early can help you address the issue promptly and prevent further complications down the line. 

Here are the four main signs that your pool pump is sucking in air: 

• Reduced Water Flow: One of the most noticeable signs is decreased water flow from the pool jets or return lines. If you notice weak or inconsistent water flow, it may be due to air entering the pump system and preventing the proper flow of water.
• Bubbles in the Pump Basket: When you open the pump strainer basket, you might see air bubbles inside instead of the device being filled with water. This is often a clear indication that air is being sucked into the pump, signifying a need for maintenance or repairs. 
• Gurgling or Whining Sounds: Unusual noises emanating from your pool pump, such as gurgling or whining sounds, can be a sign of air infiltration. Pay close attention to any unusual sounds coming from the pump during operation.
• Increased Pressure Gauge Reading: Another sign to watch for is an abnormally high-pressure gauge reading. When air enters the system, it can disrupt the flow of water and cause increased pressure within the pump and filter. Reading your pressure gauge regularly is crucial for noticing any changes or increases to the pressure in a timely manner. 

Air in the Pool Pump: 6 Causes to Know About

Now that you're familiar with the signs of a pool pump drawing in air, let's delve into the potential causes behind this issue. If you are unsure of what is ultimately causing your pool pump to suck in air, this breakdown can help you determine the root problem to discuss with a professional pool repair company. 

Here are six common causes of air in a pool pump: 

1. Low Water Level: A low water level in your pool can allow air to be pulled into the skimmer, which then makes its way into the pump. Ensure that your pool water level is maintained at the appropriate level, typically halfway up the skimmer opening or the center of the pool's tile line.
2. Pool Pump Air Leak: Pool pump air leaks can occur at various points in the system, including the pump lid, fittings, valves, or the pump housing itself. Inspect these areas for visible cracks, loose fittings, or damaged O-rings that might be allowing air to enter the system.
3. Stuck Skimmer Flap: The skimmer flap (aka the weir) is responsible for regulating the flow of water into the skimmer. If it gets stuck in the closed position, it can create a vacuum, pulling in air. Ensure the skimmer flap moves freely and isn't obstructed by any foreign objects or debris.
4. Pool Strainer Basket: The strainer basket inside the pump housing can develop cracks or become misaligned, allowing air to enter. Regularly inspect and clean the strainer basket, and replace it if you notice any damage.
5. Pool Pump O-Ring: The O-ring on the pump lid creates a watertight seal. If the O-ring becomes worn out or damaged, it can allow air to enter into the pump over time. Inspect your pool pump’s O-ring regularly and replace it if necessary.
6. Pool Pump Priming Issues: If your pool pump struggles to prime or maintain prime, it can lead to air entering the system. Ensure that all valves in the system are in the correct position and that there are no obstructions in the suction line.

How to Find a Pool Pump Air Leak

Identifying the source of a pool pump air leak is crucial for effective troubleshooting. 

Here's a step-by-step guide on how to find a pool pump air leak:

1. Visual Inspection: Start by visually inspecting the entire pump and filtration system. Look for cracks, loose fittings, and damaged O-rings. Pay close attention to the pump lid, pipes, valves, and the strainer basket.
2. Water Test: To identify leaks more effectively, you can perform a water test. With the pump running, dip a small brush or sponge into a mixture of water and liquid dish soap. Gently apply the soapy water to potential leak points. If there is a leak, you'll see bubbles forming at the source.
3. Pump Lid Inspection: Focus on the pump lid and its O-ring. Ensure that the O-ring is properly lubricated and free from any visible damage. A damaged or improperly seated O-ring is a common source of air leaks and may require a replacement.
4. Check Valve Positions: Verify that all the valves in your pool's plumbing system are in the correct position. A partially closed or stuck valve can lead to air being sucked into the system, requiring a manual correction to open the valve back up. 
5. Skimmer and Weir Inspection: Examine the skimmer and its flap (the weir) for any debris or obstructions that might be preventing proper water flow. Make sure the weir moves freely and is not stuck in the closed position.

How to Fix a Pool Pump Sucking Air

Once you have identified the source of the air leak, you can take appropriate steps to fix the issue. 

Here are some common solutions for addressing a pool pump that is sucking in air:

• Replace Damaged Components: If you discover cracked pipes, fittings, or a damaged O-ring on the pump lid or strainer basket, replace these components immediately. Ensure that all connections are secure.
• Lubricate O-Rings: If the O-ring on the pump lid or other fittings appears to be in good condition but is not sealing properly, apply a silicone-based lubricant to improve the seal.
• Repair Skimmer Flap: If the skimmer flap is getting stuck, inspect it for debris or damage. Clean and lubricate the hinge mechanism, and ensure the flap moves freely.
• Adjust Water Level: Maintain the proper water level in your pool to prevent the skimmer from drawing in air. Adjust the water level as needed to keep it within the recommended range.
• Prime the Pump: If you are experiencing priming issues, manually prime the pump by adding water to the pump housing before starting it. This helps remove air pockets and improve suction.
• Seal Any Cracks: If you find any cracks in the pump housing, pipes, or fittings, use appropriate sealant or epoxy to seal them. Ensure the sealant is fully cured before restarting the pump.

Final Thoughts: When to Reach Out to a Pool Pump Professional

A pool pump sucking in air can lead to various problems that affect the efficiency and performance of your pool's water circulation system. By recognizing the signs, identifying the causes, and following the appropriate steps to fix the issue, you can ensure that your pool pump operates smoothly.

If you cannot locate or fix the air leak on your own, it is highly advisable to consult a professional pool technician. A professional technician has the expertise and equipment necessary to accurately diagnose the problem at hand and fix it with efficiency. 

Remember that keeping your pool water clean and inviting all season long is vital. Regular maintenance and vigilance are the keys to preventing air leaks and preserving your pool pump’s longevity.