When pool equipment starts to develop a fault, there are often some early warning signs. The difficulty is that these signs are typically easy to ignore. Or, if it’s a “silent sign” like a slow drop-in performance, you may get used to the slow decline over weeks or months and not even realize it.
Your Water Clarity Hasn’t Improved Despite Longer Run Times
If you’ve been reasoning that the pool looks a little hazy so I’ll run the pump for more hours, it may be time to rethink that strategy. Less-than-perfect water clarity post-sufficient chemical treatment indicates that you’re not turning the water over at a sufficient rate, the total water volume of the pool isn’t running through filtration frequently enough to catch and eliminate all the finer suspended particles.
That can occur due to an impeller that’s partially blocked and not turning all the water it should, a filter that’s reached or passed its use-by date, or a pump that was undersized to begin with or now is due to post-installation changes to the plumbing. Which have raised the total dynamic head, the cumulative resistance to flow from pipe length, fittings and elevation changes.
When high pressure hasn’t been fixed by a good backwash, nor air leaks or unexplained noise, then specialists like Shenton Pumps should be next on the list of people to talk to. A good pump audit means you’re not throwing good money after bad.
Your Filter Pressure Has Crept up and Stayed There
There is a specific PSI level that each filter in your system has when it’s clean and the system is operating normally. Find that level and keep it in mind. If the gauge shows you’re 8 to 10 PSI over that number and backwashing doesn’t restore the PSI level, you don’t have a dirty filter, you have a blockage.
If your filter is blocked, the pump motor will draw a lot more amperage to push past it. The water still comes back to the pool, so the problem is invisible. But the motor is putting out way more heat, running way over design limits, and wearing out exponentially faster. If that’s not the problem, scaled-up piping or even a partially blocked impeller can cause similar over-amping symptoms.
Left uncorrected, the over-amping condition overstresses the motor, which can ruin the mechanical seal. Once that’s compromised, water eventually gets into the motor.
You Can See Bubbles in the Pump Basket Lid
Air bubbles inside the pump basket are more than a mere annoyance, they indicate that air is entering the system somewhere on the suction side, whether at a fitting, a valve, the strainer pot, or a leaky lid O-ring. That air is going to cause cavitation inside the pump. Tiny bubbles will form and collapse against the impeller with great force, eventually causing the impeller to degrade physically over time.
More immediately, air in the system reduces hydraulic efficiency. Your pump can’t create the same pressure with a column of mixed water and air, so your turnover rate will drop. The pool will run all day long for naught as the water fails to move through filtration at the proper rate. This often goes hand-in-hand with “spitting” at the return jets, the return water spews into the pool in uneven bursts rather than a steady stream.
The Pump is Making Sounds it Didn’t Used to Make
There are two specific noises you should never neglect to address, one is a surging or pulsing noise, a rhythmic fluctuation in the motor sound that signals the pump is waging a losing battle with air and losing prime on-and-off. This causes the motor to overheat because it’s depending on a steady stream of water to keep it cool. Run it long enough in this condition and the motor will literally melt from the inside.
The other noise is a high-pitched screech, that almost always means motor bearings have failed. The bearings keep the motor shaft steady, and when they deteriorate the shaft begins to wobble. The result is a highly inefficient motor that consumes abnormal amounts of electricity. A screeching motor is likely using 3 times the electricity it should be to produce less than its normal output.
Your Electricity Bills Have Gone up Without Obvious Reason
It’s likely you may not notice this, as energy costs tend to change slowly. But a pool pump that’s working against a restriction, air in the system, or failing bearings uses more current than a system running properly. This extra operation will cost you over weeks and months.
Variable speed pumps drastically reduce this risk, as they can be turned down to the exact level they need to operate at, instead of just running at full power 100% of the time. Upgrading from a typical single-speed pump to an ENERGY STAR certified variable-speed pool pump can save you up to $450 per year in energy costs (U.S. Department of Energy). However, a variable speed pump that’s been turned up to maximum speed in order to compensate for a blocked or doomed filter won’t be efficient, the savings only occur with well-functioning, well-maintained pumps and filters.
The same is true for the other reasons on this list, whether the pool is leaking or the lights are on for longer to make up for insufficient clarity, the equipment is incurring additional costs in order to keep water quality where it should be. Most of the time, it’s cheaper to repair or replace something in response to the first warning signs than to wait for total failure.
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Becky is the voice behind Life in Velvet, an organised, intentional living blog focused on practical food, calm homes, thoughtful projects, and everyday systems that make real life feel easier. A mum of 3 living in the UK, Becky writes from lived experience, sharing what works, what doesn’t, and the decisions that make family life run more smoothly.
With a background in marketing and content writing, and over a decade of blogging experience, she brings a thoughtful, structured approach to everything from baking and home projects to routines and decision-making. Life in Velvet is where planning meets creativity, with ideas designed for real homes and real life.