What is the best way to clean a cartridge pool filter?

Keeping your swimming pool water clean and clear is essential for an enjoyable swimming experience. The pool’s filter system plays a crucial role in removing dirt, debris, and particulates from the water. Cartridge filters are a common type of pool filter designed to trap particles as water passes through. Over time, the filter cartridges can become clogged with debris, reducing water flow and filtration efficiency. Knowing how to properly clean cartridge pool filters is important for pool maintenance. In this comprehensive guide, we will cover everything you need to know about cleaning cartridge pool filters for optimal performance.

How Do Cartridge Pool Filters Work?

Cartridge pool filters utilize filter cartridges made of pleated polyester fabric to capture particles from pool water. As water passes through the tightly pleated cartridges, dirt and debris become trapped on the surface of the fabric. The cartridges have a large surface area which allows them to efficiently remove particles 10 microns and larger. This includes leaves, twigs, sand, pollen, dust, hair, insects and other contaminants that make pool water appear cloudy. Filters are rated by how small of micron particles they can effectively filter from the water. Well-maintained cartridge filters keep pool water sparkling clean by screening out particles that reflect light and obscure visibility.

When to Clean Cartridge Filters

Cartridge filters should be cleaned whenever the pressure gauge on your filter system reads 8-10 psi above normal operating pressure. This increased backpressure indicates that debris is accumulated on the cartridges and impeding water flow. You may also notice cloudier water, reduced flow from return fittings, or overflow water from the filtration system—all signs it could be time to service the filter. For frequent swimmers or pools exposed to a lot of debris and use, cartridges may need cleaning every 2-4 weeks. Cleaning at the start of the swimming season and closing down for winter is also wise.Follow your pool filter manufacturer’s instructions for optimal timing between cleanings.

Preparing to Clean the Filter

Before beginning the cartridge cleaning process, you’ll need to take a few preparatory steps:

• Turn off the pump motor before beginning any maintenance tasks.
• Open the air release valve and allow pressure to fully escape the filter tank before opening it.
• Have all necessary cleaning supplies ready – filter cleaner solution, hose, towel, etc.
• Clear a level workspace to set the cartridges down and clean.
• Be sure proper safety gear is worn – gloves, eye protection, closed toe shoes.

Safely releasing pressure and disconnecting electricity are vital safety steps. Review your filter housing manual for the steps unique to your system. Once the pump is off and pressure is fully released, you can open the filter and remove cartridges for cleaning.

Removing the Cartridge Elements

Cartridge filters are designed for easy access to the filter media inside. Here are the general steps to follow when removing cartridges:

1. Unlatch the lock ring and turn it counter clockwise to unthread it from the filter body.
2. Lift the top half of the filter body off the lower portion. Place it upside down.
3. One by one, grasp cartridges by the handle and gently pull upwards to remove them.
4. Inspect each cartridge for tears and deterioration as you remove it. Plan to replace damaged ones.
5. Set the cartridges aside on a clean surface for cleaning. Handle them gently to avoid crushing pleats.

Your filter may have anywhere from 2 to 6 cylindrical filter cartridges. Keeping them organized will help with proper re-installation later. With the cartridges removed, inspect the interior of the filter housing for any cracks or damages. Now the cartridges are ready to be cleaned.

Cleaning Cartridges with Filter Cleaner

Filter cleaner solution formulated for cartridge filters makes washing away debris buildup quick and convenient. Here is the cleaning process using a filter cleaner:

1. Fill a bucket with filter cleaner and water per product label directions.
2. Submerge each cartridge individually into the solution, allowing them to soak for 5-10 minutes. This dissolves debris from the media.
3. Scrub each pleated surface with a soft brush or towel to help loosen up dirt. Do not use anything abrasive.
4. Rinse cartridges thoroughly with a garden hose. Spray between pleats until all cleaner residue is eliminated.
5. Shake or tilt cartridge to remove excess water. Surface should not be dripping wet.
6. Let cartridges dry completely before re-installing, usually 1-2 hours.

Filter cleaner solutions can dissolve oil, minerals, metals, organic debris, and more from the media. Follow manufacturer dilution and cleaning recommendations. Avoid using detergents or acid cleaners which could damage the cartridges. Completely rinsing away cleaner residue is essential. With a simple cleaning, cartridges are refreshed and ready for reuse!

Alternative Cleaning Methods

While filter cleaners provide an easy cleaning solution, cartridges can also be washed using:

Dish Soap – Mix a few tablespoons of dish soap into a bucket of warm water. Allow cartridges to soak before scrubbing each pleat surface with a soft brush. Rinse thoroughly. Avoid using abrasive scrubbers.

Power Washer – An electric pressure washer on a moderate setting can be used to spray cartridges with water to force out trapped debris. Take care not to damage the media.

Vinegar or Lemon Juice – A 50/50 mixture with water can dissolve mineral buildup and other deposits. Let cartridges soak before rinsing. Avoid using vinegar long-term as acidity could damage materials.

Pool Shock – Calcium hypochlorite or sodium hypochlorite shock treatments can oxidize and dissolve organic oils and waste. 1 tbsp per gallon of water. Handle chemicals safely.

While chemical cleaners offer convenience, household products provide an effective, natural cleaning solution in many cases. Never use harsh chemicals like chlorine bleach or muriatic acid which could ruin cartridges.

Disinfecting Cartridge Media

In addition to cleaning, you may wish to periodically disinfect your filter cartridges to destroy bacteria, fungi, algae, and other microorganisms that can accumulate in pool filters over time. Here are two methods:

1. Pool Shock Treatment

• Use calcium hypochlorite or sodium hypochlorite shock.
• Mix 1 tablespoon shock per gallon of water in a bucket.
• Submerge cartridges and soak 20-30 minutes.
• Air dry completely before reinstalling.

2. Cartridge Filter Cleaner with Sterilizer

• Look for filter cleaners containing an algaecide or fungicide.
• Follow product label for correct dilutions to sanitize.
• Soak, rinse and air dry cartridges.

This helps ensure all contaminants are eliminated from the filter media between cleanings.

Reinstalling Filter Cartridges

Once fully dried, cartridges can be reinserted into your pool filter system:

1. Inspect filter interior and o-ring for damage. Replace o-ring if worn.
2. Insert cartridges one by one in the proper configuration according to your filter manual.
3. Be sure cartridges are fully seated down into the lower filter base.
4. Replace the filter top, threading the lock ring back onto the tank.
5. Turn on pump motor and allow filter to prime before scaling valves up to full flow.
6. Check for leaks as system re-pressurizes.
7. Refer to manufacturer instructions for proper reassembly of your specific unit.

With clean cartridges secured into the filter tank, normal system operation can resume. Initially check the pressure gauge to confirm there is no longer an elevated backpressure reading on the system. Nor should you observe cloudy return water.

When to Replace Cartridges

Over years of use, accumulated dirt and chemicals from cleaning will gradually degrade and damage cartridge filters. Replacement is recommended every 3-5 years or when:

• Fabric pleats appear melted, misshapen, brittle or torn
• The cartridge frame is cracked or damaged
• Deep set stains or calcium deposits no longer wash away
• Flow and filtration performance remains poor after cleaning
• When replacing with newer cartridge models

Consult your filter manufacturer for cartridge lifespan estimates. Keep spare cartridges on hand for easy change-outs when worn ones require replacement during maintenance cleanings.

Helpful Cartridge Filter Cleaning Tips

Follow these tips for most effective cartridge filter cleaning and care:

• Clean cartridges when pressure reads 8-10 PSI above normal.
• Carefully release air pressure before opening filter.
• Rinse away all cleaner before reinstalling.
• Allow 2 hours minimum for thorough drying time.
• Inspect cartridges closely each cleaning for damage.
• Soak extremely dirty cartridges overnight before scrubbing.
• Alternate or replace chemical filter cleaners periodically.
• Lubricate o-rings with non-petroleum jelly before replacing.
• Mark dirty sides of cartridges to rotate each cleaning.

Proper maintenance keeps these vital pool filter components clearing water of debris for years of untroubled swimming enjoyment.

Conclusion

Cartridge pool filters provide an effective and affordable way to keep water free of dirt, leaves, pollen, and other debris that reduces clarity and cleanliness. While simple in design, cartridges perform best when properly maintained by periodic deep cleanings. This guide reviewed when cartridges need cleaning, how to remove them from the filter housing, proven cleaning methods using filter cleaners or alternative DIY solutions, and best practices for disinfecting, reinstalling and replacing cartridges when worn out. Following these steps for cleaning your cartridge filter will minimize required maintenance and extend the useful lifespan of these inexpensive filter elements for optimal water filtration performance season after season. Clean cartridges mean clean pool water your family can safely enjoy all summer long.