Cleaning and Replacing Pool Cartridge Filters

Cleaning and Replacing Pool Cartridge Filters

You know you have a cartridge filter system for your pool, and you know you want your pool to be clean all season. But now that your pool is set up and running, questions are popping up in your head. “When do I need to clean the filter? Should I just replace the whole filter? How hard is this going to be? What have I gotten myself into?!” Well, you’ve come to right class! Pool filter cartridge cleaning and replacement is not difficult. We’re going to give you the run-down on when to clean and when to replace your cartridge filter so you and your family will be swimming in clean, clear waters all season long. 

When to Clean Your Pool Filter Cartridge

Your pool filter should have a pressure gauge that helps you determine how the pressure is holding (or not holding) in your pool. When your filter pressure gauge increases by about 8 PSI or more above the normal operating pressure, then it’s time for you to clean the filter cartridge. For example, if the normal operating pressure is 10 PSI and you see the gauge is reading 19 PSI, it is time to clean to the filter cartridge.

Other times you should clean your filter include:

  • Every six months if it hasn’t been done 
  • During an algae bloom treatment
  • After major storms
  • As part of opening or closing your pool

Cleaning your cartridge filter is a very important step in maintaining your pool and pool filter system. Check out this great article for a how-to guide for cleaning your pool filter cartridge and the products you may need.

When to Replace a Filter Cartridge

Generally, filter cartridges should be replaced about every 3-5 years. This is a broad range because the demand placed on the filters will vary from family to family based on your family size, frequency of use, etc. Instead of using time as the determining factor for filter replacement, it is best to monitor the performance and appearance of the cartridge filter. Here are some signs that suggest it’s time to replace your cartridge filter.

1. Pool Water Quality

If you notice your water is still looking cloudy and green even after you’ve cleaned out your filter cartridge, this is an indicator that your filter cartridge needs to be replaced. The cartridge is probably unable to filter the water as effectively as it once did because each time a cartridge is cleaned, the fibers separate a little bit more, allowing fine dirt and algae to pass through unfiltered. 

2. Frayed Fabric

When you pull out the filter cartridge to do your usual cleaning and notice that the cloth looks frayed or has a “furry” look to its surface, that’s a definite sign that a replacement is necessary. This furriness is caused by the tiny fibers ripping apart, and the fibers ripping apart indicate the material may begin to fail. Any holes in the material provide dirt a debris a direct path right back into your pool making the filter now inefficient. 

3. Broken End Caps

The plastic end caps on your filter cartridges are integral to the structure of your filter - they keep the filter material in a tight compact form. Most end caps are made of heavy-duty plastic, making them durable, however end caps are susceptible to wear and tear because of the harsh water chemicals in which they are constantly submerged. End caps can become brittle and broken, so it is best to replace cartridges right away when this happens. If a cartridge with a broken end cap is repeatedly used, a broken piece could circulate through the filter system causing equipment damage.

4. Crushed Cartridge

A crushed cartridge occurs when the inner core collapses. The inner core of your cartridge is the plastic reinforcement cage that backs the pleats, preventing collapse.  A failure of this type will cause the cartridge to resemble a crumpled soda can with pleats. The likely suspects for this issue are an already cracked inner core, sub-standard cartridges, or a cartridge that was too small. The latter commonly occurs when a pool owner buys the incorrect cartridge size but installs it anyway. It’s important to properly replace the filter cartridge with the correct size.

So that’s the dirt on when to clean and replace filter cartridges. With regular maintenance and upkeep, your filter is sure to be in tip-top shape, and your pool will stay clean and clear all season long!

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