If you’ve noticed that one of your pool skimmers isn’t working properly, you’re not alone. A non-functioning skimmer can be a major annoyance—if not a precursor to more serious pool maintenance issues. Skimmers play a critical role in catching debris like leaves, bugs, and other floating matter before they sink and contaminate the pool water. When one of your skimmers is underperforming or completely dead, water quality can drop, and cleaning routines become increasingly burdensome.
This comprehensive guide will help you understand why one of your pool skimmers might be malfunctioning, how to diagnose the issue, and what steps you can take to resolve it. Whether you’re dealing with low suction, clogging, or a complete lack of operation, this article is your one-stop resource for all things skimmer-related.
Understanding How Pool Skimmers Work
Before diving into potential issues, it’s important to understand the basics of how a pool skimmer works. A skimmer is essentially a water intake opening located near the water surface level of the pool. As water circulates through the pool system, it flows into the skimmer, which pulls surface debris along with it.
Inside each skimmer, you’ll typically find the following components:
- Skimmer basket – This collects larger debris
- Weir – A swinging flap that helps regulate water flow and prevent backflow of debris
- Equalizer line – A small pipe that connects below the pool’s main drain to prevent the pump from running dry if the water level drops too low
- Suction line – Connects the skimmer to the pool pump
Most in-ground pools have multiple skimmers, each feeding into the pool’s circulation system. If one is not working as effectively as the others, there can be a variety of reasons—most of which are fixable without professional help.
Common Reasons Why a Pool Skimmer Stops Working
There are several potential causes for a skimmer malfunction. Let’s break them down and explore each thoroughly.
1. Low Water Level
One of the most common—and easiest to fix—reasons a pool skimmer isn’t functioning is water levels. If the water level is too low, the skimmer will struggle to pull in surface water effectively. Likewise, if the water level is too high, it may bypass the skimmer entirely.
Quick Tip: The ideal water level should be halfway up the skimmer opening. Anything below this will inhibit the skimmer’s efficiency. Adjust water levels with a garden hose or through the pool’s automatic refill system, if equipped.
2. Clogged Skimmer Basket or Plumbing Line
Another frequent issue is debris buildup inside the skimmer basket or in the plumbing line leading to the pump. Over time, leaves, hair, sunscreen residue, and other materials can accumulate and restrict water flow.
Warning: A clogged skimmer doesn’t just reduce effectiveness—it can also cause airlocks in the system, increasing wear on your pool pump and filter.
To check:
- Remove the skimmer lid and basket
- Inspect for compacted debris
- Clear out any obstructions
- Ensure the suction line (just below the basket) is also clear
You can also attach a garden hose to the skimmer and gently backwash the line to clear any deeper blockages. This helps restore normal operation.
3. Air Leaks in the Suction Line
When a skimmer isn’t drawing in water, it may instead pull in air. This disrupts the seal that makes the system work and can cause your pump to lose prime. The source of air intrusion is typically from a loose skimmer lid or damaged piping.
To identify air leaks:
- Start by making sure the skimmer lid is seated properly with a tight seal
- Check the union connection near the pump for loose fittings or damaged o-rings
- Visually inspect for deteriorating pipes or connectors under the skimmer
Even a small leak can create enough air to disrupt the skimmer and the overall filtration process.
4. Blockage in the Main Drain Line
Pools with two or more skimmers often share suction lines with a central main drain. If another section of the system is blocked, it can impact the skimmer you’re currently having trouble with.
In this case, check both your main drain and other skimmers for reduced suction. If they’re performing normally, then it’s likely an issue isolated to the malfunctioning skimmer. However, if multiple suction lines are affected, the problem probably lies further back in the system, such as in your valves or pump.
5. Faulty Multiport Valve Position
If you have a sand or DE filter system with a multiport valve, incorrect positioning could prevent water from passing through the affected skimmer. Check the settings on your multiport valve:
- Filter (normal setting)
- Backwash
- Rinse
- Recirculate
Make sure each setting lines up correctly with the function you’re trying to perform. Even a slightly misaligned dial can interfere with flow dynamics.
6. Damaged or Missing Weir
The weir is the flap that moves up and down with the water’s surface. If your skimmer has a broken weir or none at all, water may not flow efficiently into the skimmer, especially during calm conditions or periods of heavy sun evaporation.
Caution: A damaged weir often breaks from improper installation or wear and tear over time. Replacing it is relatively simple and keeps your pool operating optimally.
How to Diagnose a Faulty Pool Skimmer Step-by-Step
Understanding how to properly diagnose the issue can save you time and money. Let’s go through the process step by step to identify the root cause and get your skimmer up and running again.
Step 1: Observe the Skimmer Operation
Turn on your pool pump and observe the problematic skimmer. Watch if:
- There’s any suction at all
- Water is flowing slowly or in reverse
- There is visible air coming through the skimmer lid
If the skimmer is completely stagnant, it’s likely choked or disconnected somewhere in the system.
Step 2: Check the Water Level
As mentioned earlier, improper water levels are a quick and common culprit. Confirm the water level visually—skimmers only work when the water enters their designated intake area.
Step 3: Clear the Skimmer Basket and Suction Opening
Empty the basket and use a small brush or garden hose to clear the suction line opening located just underneath. If the water starts flowing normally after cleaning, the issue was simple clogging.
Step 4: Inspect the Weir and Lid Seal
Make sure the weir is intact and the lid is seated properly. Look for warping, cracking, or damage. If the lid doesn’t form a complete seal, it could be causing the pump to draw air instead of water.
Solution: Replace the weir or skimmer lid gasket if needed. These components are relatively inexpensive and critical for proper skimmer performance.
Step 5: Check for Leaks in the Plumping
To test for air intrusion:
- Turn off the pump
- Brush on soapy water along any visible plumbing connected to the skimmer
- Turn the pump back on and watch for bubbling
If you detect bubbles, this indicates an air leak that needs sealing or replacing.
Step 6: Evaluate the Multiport Valve and System Suction Balance
If you have multiple skimmers or a main drain, it’s possible that the suction has been unevenly distributed. Try adjusting the suction valves or equalizers to shift flow toward the malfunctioning skimmer momentarily.
Additionally, test the pump for appropriate pressure and flow rate to rule out mechanical issues in the filtration unit itself.
When to Call a Professional
While many skimmer issues can be resolved with basic troubleshooting and DIY maintenance, some problems fall outside the scope of average homeowners. Signs you should seek help from a licensed pool technician include:
- Signs of leaking underneath the skimmer or in the walls of your pool
- Skimmer body is cracked or showing structural damage
- Persistent loss of prime or low pressure even after clearing all visible obstructions
- The system frequently requires resetting or manual clearing just to function properly
Persistent skimmer issues can also point to broader circulation problems that affect the longevity of pumps, filters, and chemical balance.
Preventative Maintenance Tips for Pool Skimmers
Let’s look at ways to keep your pool skimmers working hard all year round without hassle:
1. Regular Cleaning
Establish a cleaning schedule—ideally, once a week during peak pool season. Empty the basket, rinse the suction port, and remove any visible debris buildup. If your pool sees heavy organic traffic (i.e., tree cover, insects), consider cleaning more frequently.
2. Monitor Water Levels
Keep an eye on the water level, especially after heavy rain or summer evaporation. Use a marker line in your pool if you need a visual guide. Maintaining proper water balance also helps the skimmer work efficiently.
3. Replace Worn Components
Gaskets, weirs, and skimmer baskets don’t last forever. Plan to inspect and replace these components every season or as needed if they show damage or deterioration.
4. Backwash and Pump Maintenance
Don’t forget to treat the pool pump, specifically the pump basket, as part of your skimmer health. If your pump basket is clogged, that can also reduce flow to skimmers. Regular backwashing keeps your filtration system functioning optimally.
5. Seasonal Skimmer Care
In climates where pools are closed for winter or periods of non-use, drain the skimmer and any connected lines to avoid freeze damage. Use airbags or foam in the skimmer throat and seal the lid tightly to prevent cracking.
Wrap-Up: Keeping Your Pool Skimmers in Top Condition
Whether you have one or multiple pool skimmers, they are a vital part of keeping your water clean and safe. Understanding how they work, identifying where a failure might be occurring, and applying troubleshooting steps can often resolve most skimmer-related issues.
From water levels and debris buildup to structural wear and air leaks, many solutions are quick, cost-effective, and simple to perform. However, if you detect persistent or complex problems—like cracked skimmer walls, plumbing leaks, or motor troubles—it’s wise to call a pool service professional to avoid lasting damage.
By maintaining good habits and promptly addressing signs of trouble, you can enjoy fewer maintenance headaches and a crystal-clear pool all season long.
If you found this article helpful, consider sharing it with other pool owners or bookmarking it for future reference. Keep your pool skimmers active—and your water sparkling!
Why is my pool skimmer not drawing water?
There are several reasons why a pool skimmer might not be drawing water effectively. One common cause is a blockage in the skimmer basket or the pipe leading from the skimmer to the pump. Over time, leaves, dirt, and other debris can accumulate and restrict water flow. Another possible issue could be an air leak in the system, which prevents the pump from priming properly. Checking the skimmer basket, cleaning out any debris, and inspecting for cracks or poor seals can help resolve this issue.
Additionally, the water level in your pool may be too low, preventing the skimmer from functioning correctly. A skimmer requires the water to be at the proper level—roughly halfway up the skimmer opening—to draw in surface water efficiently. If the water level is too low, the skimmer might pull in air instead of water, leading to poor circulation. Adjusting the water level and ensuring the pump is operating correctly can often restore the skimmer’s functionality.
Can a broken skimmer weir cause my skimmer to stop working?
Yes, a damaged or missing skimmer weir can definitely impact the performance of your skimmer. The weir is the small flap at the front of the skimmer that controls the flow of water into the skimmer. It helps maintain a consistent flow and prevents debris from escaping back into the pool. When the weir is broken or stuck in place, the skimmer’s efficiency can be reduced, causing it to draw in less debris and operate less effectively.
Replacing a broken weir is a relatively simple fix that can significantly improve your skimmer’s performance. Weirs are made of plastic or rubber and are designed to float slightly, allowing them to adjust to changing water levels and flow. If your weir is damaged, visit your local pool supply store to find a compatible replacement. Once installed, the weir should restore the skimmer’s ability to draw in surface water and trap floating debris properly.
What role does the pool pump play in skimmer performance?
The pool pump is essential for the operation of your skimmer system because it creates the necessary suction to draw water from the skimmer into the filtration system. If the pump is not running properly or is clogged with debris, it can reduce the flow of water through the skimmer. Additionally, if the pump loses prime or is not adequately sized for your pool, you may notice one or more skimmers not working effectively.
It’s important to regularly inspect the pump impeller and pump basket for blockages, as these can hinder water movement through the system. Air leaks in the pump’s lid or plumbing connections can also reduce suction power, making it difficult for the skimmer to function correctly. Ensuring the pump is in good working condition, free of leaks, and running for the appropriate amount of time each day can help maintain optimal skimmer performance.
How does a clogged skimmer basket affect skimmer operation?
A clogged skimmer basket can significantly reduce or even stop the skimmer’s ability to draw in water. The basket is designed to collect leaves, bugs, and other floating debris before they enter the pump and filtration system. However, when the basket becomes too full, it blocks the flow of water, causing the skimmer to underperform. This can result in standing debris on the pool surface and poor circulation from that particular skimmer.
To prevent this issue, it’s recommended to clean the skimmer basket regularly, especially during periods of heavy debris or after storms. If you notice that one skimmer is not working while the other(s) are functioning normally, a blocked basket might be the culprit. Simply removing and emptying the basket, then rinsing it clean, can often restore the skimmer’s performance and help maintain proper water circulation.
Can pipe blockages affect only one skimmer?
Yes, blockages in your pool’s plumbing lines can affect just one skimmer without impacting the others. This usually occurs when debris accumulates in the dedicated pipe that connects a specific skimmer to the pump. Since each skimmer is typically on its own line, a blockage in one won’t necessarily interfere with the others, which can lead to uneven skimming performance across the pool.
Diagnosing a pipe blockage can sometimes be done by checking how much water flows out of each line individually. If you suspect a line is blocked, using a garden hose to flush it backward or employing a plumber’s snake specific for pool lines might remove the obstruction. In severe cases, professional assistance may be necessary to fully clear the line and restore proper water flow to that particular skimmer.
Why is only one of my multiple skimmers working?
If your pool has multiple skimmers and only one is functioning properly, the issue could stem from improper water flow distribution. This can happen if the lines feeding the non-working skimmer are blocked or if the flow is unevenly balanced between the skimmers. Some systems include a valve that allows you to regulate the water flow between skimmers, and if that valve is closed or improperly adjusted, it can shut off or limit water flow to one or more skimmers.
Additionally, structural issues like collapsed pipes, poor plumbing design, or age-related wear can impact the less-functional skimmer. It’s also possible that the suction port or basket of the underperforming skimmer is damaged or not seated correctly. Examining the plumbing, opening or adjusting any valves, and inspecting skimmer components can help identify the issue and restore equal performance across all skimmers.
How can I prevent skimmer problems in the future?
Regular maintenance is the best way to prevent skimmer problems and ensure consistent pool operation. This includes routinely cleaning the skimmer baskets, inspecting the weirs for damage or wear, and checking the water level to ensure it remains within the ideal range. By staying proactive, you can avoid clogs and inefficiencies that disrupt the skimming process and potentially damage the pump and filtration components.
In addition to routine cleaning, periodically inspecting the plumbing lines and pump for signs of wear, leaks, or blockages can help prevent future issues. If your pool system includes adjustable valves for multiple skimmers, ensure they are balanced properly and not restricting flow to certain areas. Regularly running the pump for recommended durations and keeping the pool covered during high wind or debris periods will further help maintain optimal skimmer function and extend the life of your overall pool system.