
- Categories: Pool Fixing
Pool pump troubleshooting: the solution you are looking for is here!
Pool pumps help to keep your water clean and safe to enjoy. They’re an essential part of your pool maintenance. But like any equipment, they can break down due to a number of problems.
Fortunately, many of these issues are fixable without calling in an expert. So in this guide to swimming pool pump troubleshooting, we’ll help you diagnose common pump issues and provide advice on what to do about them.
And if they don’t work, where you can get professional help.
In this pool pump troubleshooting guide:
Pool pumps: which bit is which?
Before we get into the nitty gritty of pool pump troubleshooting, here’s a quick refresher of pool pump parts and what they do:
- Pool pump lid: The super durable pool pump lid is the first place you can check the health of your filtration system. Bubbles or no water are both a sign of issues.
- Strainer housing: Water is collected here first to be filtered from debris.
- Drain plug: This is used to drain the pump in preparation for winter or periods of no use – it’s not commonly used here in New Zealand.
- Housing with impeller: The control centre for your pump. The impeller spins on the motor shaft to pump water from your pool to its filter. You’ll also find the diffuser and seals here which help the impeller function.
- Capacitor: Like a car battery, the capacitor gives your pump a jolt of power to get started. They usually have around 5,000 starts in their lifetime, which sounds like a lot, but runs down quickly.
- Motor and shaft: These spin the impeller and power the pump.
- O-rings: These are simply the little rubber rings used to seal joints. They’re super important though, because wear leads to leaks and expensive damage.
3 signs your pool pump is on its way out
You should get a good eight to ten years out of a well-maintained pool pump.
But if the following things are happening, at-home pool pump troubleshooting may not solve your problem.
1. Constant leaks
We talk a bit about fixing different types of leaks below. But if you’ve done most of these numerous times now, it could be the seal on your motor shaft that has worn out.
This can sometimes be patched up, but if the problem persists, you may need to replace the pump.
2. Low pressure
If your filter pressure gauge is consistently low and you’ve tried all our tips below for clearing blockages, your impeller may be clogged with debris or wearing out.
3. Losing prime
Priming your pool pump involves flushing out the system of excess air. You want a vacuum effect that pulls in the water and forces out air.
If this is consistently failing, your pool water won’t be filtered properly. This causes a build up of debris and eventually, algae blooms.
You might need to replace your entire pump.
My pool pump is not turning on
If your pool pump is connected to a power source but not turning on, try the following:
- Check your pump timer: Is your pump set to turn itself off?
- Check the breakers: You might have tripped these during a cleaning session, or they might have tripped during the night.
- Check the pump wires: If you have an issue with pests like rodents, they may have made a meal of your electrical wires – literally! Turn off the power before inspecting.
My pool pump starts but quickly switches off
It’s often an electrical overload or failing capacitor that causes this problem.
- New pumps: If your pump is newly installed, get an electrician to check this out. There’s probably a voltage problem which isn’t something you want to play around with.
- Older pumps: If your pump has been installed for a while, then you might have a loose connection or failing capacitor. Try tightening up the wires and connections first. If that doesn’t work, you might need to investigate your capacitor.
If your pump runs for a while before switching off:
- Check the motor: It could be hot, so watch out. If it is, then overheating could be triggering the motor to switch itself off as a safety measure. Check your motor vents to ensure nothing is blocking them so the fan at the back of the motor can blow cooling air over the pump motor. On most pumps the thermal overload switch will reset itself once the motor has cooled sufficiently.
- Are you using a timer? If you wire your pump directly to the breaker and don’t use a timer, this could be the issue. Circuit breakers aren’t designed to be on/off switches and can wear faster. A motor starting switch could be a good solution, but you’ll want to consult an electrician about that.
- Are you using the right voltage? An overloaded circuit can causing overheating and a trip. You can try the pump on a different electrical circuit and if it then runs OK then you would probably need to talk to your electrician.
My pool pump isn’t pulling in or circulating water
This is probably due to a blockage somewhere. If the pump runs for too long without sufficient water flow, it will “run dry” which will lead to costly repairs. Try the following:
- Check your filter gauge: If it reads around 10psi/50-60 kPa above the usual number, clean out your filter. This should reduce the pressure in the filter and help the pump’s water flow.
- Clear the pump: Clean out the skimmer, pump basket and impeller of any debris. Check that the pump basket hasn’t split. It may need replacing.
- Check for leaks: Inspect your pipes to ensure there aren’t any leaks. If there are, scroll down to our leaks troubleshooting tips.
My pool pump is sucking in air
That’s not ideal, but there are plenty of things you can try if you see a steady stream of bubbles returning to the pool after the pump has initially primed – unless you have an Ozone system fitted:
- Check your water levels: If your waterline has dropped below your pool skimmer, it won’t pull water and air can be sucked in instead. This is an easy fix, simply refill your pool water to at least halfway up your skimmer. You can opt for automated pool equipment or a leveller that will keep track of this for you.
- Clear your skimmer and pump basket: If these are blocked by debris, the water won’t get through. Also check that your basket isn’t split so debris cant get into the pump.
- Check your skimmer weir doors: If these are stuck, your water flow will be impacted. Another super easy fix!
- Check the pump itself: Make sure the pump, intake lines, and accessories are all intact. Any cracks, breakages or faulty seals/O rings might be inhibiting the water flow.
- Check your pump lid o-ring: Can you see bubbling or hear a hissing sound around your pump lid? There might be some debris stuck, so try clearing that first. If that doesn’t fix the problem, you may need to lube or replace the o-ring.
- Check your union o-ring and suction side for leaks: Unfortunately it’s harder to spot problems with these o-rings, so you’ll need to get creative. One way to diagnose the problem is to bubble up some detergent and cover the joints and couplings. If the bubbles look like they’re being sucked in, you could have a suction side leak.
- Check your intake lines: These might be clogged. You’ll need to test each line individually to find out where the problem is. Switch all others off except the one you want to test and check the filter pressure gauge. If one has a lower line than the others, you’ve found your blockage. Use a hose jet to clear the problem or contact your pool professional.
My pool pump is leaking
Pool leaks can come from a number of different places, so you’ll need to get up close and personal with your pool pump to find the source.
Unfortunately, if the leak is coming from the pump itself, you might have a big problem.
Look at:
- The pump itself: Any visible cracks you can see? Are bolts on tightly and o-rings secure? Is the lid on properly? Check the motor, are any parts showing wear?
- The joining between the pump body and motor: If there’s a leak here, your mechanical seal might be failing. And unfortunately, this will only get worse over time. If water bypasses this seal and reaches the pump motor, it’s game over, so jump on this issue as early as possible! You’ll probably need professional help here.
- The pipe threads: These connect outlet and inlet pipes to the pump. Threads can overheat, melt and shrink which causes leakage.
- The shaft seal: This is inside the pump housing and stops water from getting into the electric motor. Over time, these can wear down and cause leaks underneath the pump.
My pool pump loses pressure after a few minutes
If your pump is losing pressure, the most likely causes are:
- Clogs: Clean out your skimmer, basket, and impeller of any debris. If the problem persists, try checking the filter pressure gauge for your intake lines. To do this, take it in turns to leave one line connected to your pump while you turn all others off, and check the pressure levels. The line with the lowest level may have a blockage.
NB: Never close all valves with the pump running! At least one should always be open.
- Leaks: These can occur in the pump itself and at joins in the equipment and lines. They’re often due to wear and can sometimes lead to costly replacements, so don’t leave them too long! Check the mechanical seal between the pump body and motor, any pipe threads, and the shaft seal inside the impeller. Some leaks will allow air to enter the pipework and reduce the water flow.
- Dirty filter: If your filter is blocked up or needs cleaning, it’s important to fix this quickly before algae develops. Regularly cleaning your filter will prevent blockages and help keep your water balanced and safe.
My pool pump is making a roaring or pulsing sound
This might indicate that your pump has no water flow. This is usually caused by a blockage or a leak.
Check your skimmer, basket, weir doors, and intake lines for blockages.
My pool pump is vibrating loudly
Some vibration is normal. But if you’re noticing abnormal levels of vibration coming from your pool pump, check out the following:
- Is it on a firm base? The pump will move a little when it’s working normally, so it may have shifted position. Check this first as it’s an easy fix.
- Are the bearings worn? Worn bearings can misalign the shaft of the pump and cause shaking. You can replace these yourself with the right tools, or contact your pool professional. Just make sure you do to avoid needing to replace your entire pump!
- Is it sucking in lots of air? Scroll up to our section on this to work through the potential causes. It could be your water level, issues with your skimmer, or a blockage or leak somewhere.
My pool pump is making a loud humming noise
There are two main causes of this problem in pool pumps:
- A clogged impeller: This is a common cause of a humming pool pump. All you need to do is clean out your impeller. Just make sure you’ve switched off the pump and disconnected it from its power source first.
- A failing capacitor: This isn’t such an easy fix. If your capacitor is failing to give your pump the power it needs to start, it will need to be replaced. That’s doable, but opening up your pump’s motor to find the part is tricky. You might want the help of a professional to avoid any further damage or electric shocks!
My pool pump is making a screeching noise
This is likely to be a bearing and/or a shaft seal problem.
You can replace bearings and shaft seals relatively easily, but it may be best to get professional advice on the tools and equipment to use.
Getting help: swimming pool pump repairs
If you’ve tried a few of these swimming pool pump troubleshooting tips without success, it might be time for a professional pool pump repair.
If you purchased your pool pump from us (or one of our dealers), fill out this simple form and we’ll be in touch.
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Hey! I'm Adrian, founder and pool expert here at Dolphin Pacific. I love spending time with family, fishing, and have been known to brew my own beer.