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How to Fix a Low-Pressure Swimming Pool Pump

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Learn these easy tips to troubleshoot your pool pump problems and turn that cloudy, dirty water back to crystal clear.

Learn these easy tips to troubleshoot your pool pump problems and turn that cloudy, dirty water back to crystal clear.

What to Do If Your Pool Cleaner Isn't Working

It's been looking and feeling a lot like summer these last few days, with temperature highs reaching the mid-90s where I live. I have a swimming pool, but unfortunately, the water isn't looking very clean.

Lately, I've noticed that the pool cleaner hasn't been working very well. Leaves from the neighbors' trees and other debris blown in by the wind are settling at the bottom of the pool. Normally, I would see them for no more than a day, but it seems like they are hanging around longer and not getting sucked up by my pool cleaner. I have a Kreepy Krauly Classic suction-side in-ground swimming pool cleaner.

Whenever I see this happen, I check these five things in the following order (from the easiest to the most difficult to deal with).

What to Check Before Calling the Pros

Scroll down for more information on each of these five items.

  1. Water Level
  2. Skimmer Filter
  3. Pool Cleaner
  4. Pre-Pump Filter
  5. Main Water Filter
Kreepy Krauly cleaning my pool

Kreepy Krauly cleaning my pool

1. Check the Water Level

When the water level starts to get low, the skimmer begins to take in air. When this happens, you'll start to hear a bubbling sound, and bubbles may come out of the water nozzles in the pool.

You will also start to hear the water pump cycle through fast and slow revving. When you hear this, it means that the pump isn't filtering as efficiently as it could be since it is pulling in air which it cannot really filter.

The solution to this is to open the valve that fills the pool with water and wait until it is at the correct level again, then shut off the water valve when done. You could also just use a garden hose to fill it up.

Skimmer with correct water level.

Skimmer with correct water level.

2. Check the Skimmer Filter

The next thing to check is the skimmer filter.

The skimmer filter is in the small opening on the side of the pool where surface water and anything floating on it are sucked into the filtering system. The skimmer filter is like a basket that catches leaves, grass, and other small things that float on the surface of your pool.

If you neglect the skimmer filter and it gets clogged up, the pressure in the water pump will drop. When the pressure drops, the pump cannot work efficiently—resulting in a pool that gets dirty faster than it can be cleaned.

The easiest thing to do to fix this problem is to lift the skimmer lid, take the filter out, clean it, and then replace it.

In my pool, I have occasionally neglected to check this filter and it has become clogged. I once had a small canvas sheet that came from my neighbor's canopy completely clog the skimmer! Fortunately, that was an easy fix.

Lift the lid, remove the skimmer basket, dump it out, and replace the basket and cover.

Lift the lid, remove the skimmer basket, dump it out, and replace the basket and cover.

3. Check the Pool Cleaner Itself

If the water level is good and the skimmer filter is clean, but the pool cleaner still doesn't seem to suck in the dirt at the bottom of the pool, it's time to check the pool cleaner itself.

Most pool cleaners now use kinetic energy to move along the bottom of the pool. This kinetic energy comes from a little piece of plastic in the intake of the pool cleaner that oscillates back and forth. As the little piece of plastic is getting sucked in through the pool cleaner hose, it bounces back and forth causing vibrations that propel it forward.

A normal operating pool cleaner, like the Kreepy Krauly model I have, will cause the water by the hose to ripple. If you aren't seeing the rippling, or the rippling isn't as strong as before, it is time to check the bottom of your pool cleaner. There might be something stuck in there.

On a couple of occasions, I discovered a pool toy had been sucked into the cleaner. I simply pulled it out, and the cleaner began working again.

4. Check the Pre-Pump Filter

The pre-pump filter is the next area to check. This filter is similar to the skimmer filter in that it is designed to catch medium- to large-sized debris before the water goes into the water pump.

The pre-pump filter typically has a transparent cover so you can see a bit of what's flowing inside. If it is starting to look dark or you can't see the filter walls, then it may be time to open the pre-pump filter cover and clean the filter itself.

If this filter gets clogged, the water pump pressure will drop significantly. When the pressure drops, the cleaning system will not work well. So take the plastic filter out, clean the dirt or debris buildup, then replace it. Make sure the cover is hand-tightened so as not to overtighten it.

Once you've cleared the filter and replaced it, the water pump and pressure should start sounding and looking normal.

Pre-pump filter with transparent lid on.

Pre-pump filter with transparent lid on.

Empty the basket and hand-tighten the lid.

Empty the basket and hand-tighten the lid.

5. Check the Main Water Filter

The main water filter should be cleaned every six months. If you are like me, I sometimes go longer than six months. An extended period of time where the filter isn't cleaned will cause it to clog. When a filter is clogged, the water pump cannot work effectively because the water pressure drops. At this point, the pool cleaning process can't keep up with the dirt or debris buildup.

I put this particular one last because I dread cleaning the main water filter. It takes a lot of time to remove the cover, remove the inner and outer filters, clean each of the filter elements, then clean the filter housing bottom.

However, if you've checked everything and the pool cleaning is still not working as it should, it is time to open and clean the main water filter.

Final Checklist Before You Call the Pros

It's getting hot and you're ready to jump into your pool, but the pool looks crappy. What do you do?

  1. Check the water level.
  2. Clean the skimmer.
  3. Inspect the pool cleaner itself.
  4. Clean the pre-pump filter.
  5. Clean the main water filter

If none of the above fixes your problem, it is time to call in the pros.

You'd better get going. It's getting hot out there!

Further Reading

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.


Dewald Lotter on October 13, 2019:

Istalled a new pump, no leaks vissible, primed the pump and started it up. Pump is pumping good as soon as i close the weir lid the pump cavitate

Rob Hampton from Port Richey, Florida on February 25, 2015:

Good Article!

J Forlanda (author) from US of A on March 02, 2013:

You are welcome. Hopefully it has given you some ideas of possible pump problems in the future and what can be done about them.

Suzy Frame on February 18, 2013:

Thanks so much for sharing this! I just got a new pool and have been having problems with its pump! I tried to fix it on my own but I think I will resort to calling calgary plumbers to see what they tell me to do or how they can help me! Thanks so much for sharing!