Water flows through a pool filter by being drawn from the pool, processed to remove debris, and then returned to the pool. Here's a detailed breakdown of the process:
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Water Intake: The pool water is drawn into the filtration system through two main entry points:
- Skimmer: This surface opening collects leaves, insects, and other floating debris.
- Main Drain: Located at the bottom of the pool, the main drain draws water from the deeper areas, helping to circulate the entire pool volume.
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Pump Action: From both the skimmer and the main drain, the water is pulled into the pool pump. The pump creates the necessary suction to draw water from the pool and provides the pressure needed to push it through the filter.
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Filtration Process: After leaving the pump, the water enters the pool filter. Different types of filters work in slightly different ways:
- Sand Filters: Water is forced through a bed of sand. The sand traps dirt and debris, allowing clean water to pass through.
- Cartridge Filters: Water passes through a pleated filter cartridge made of paper or synthetic fabric. The cartridge traps particles as small as 10-20 microns.
- Diatomaceous Earth (DE) Filters: Water flows through a grid coated with DE, a fine powder made from fossilized algae. DE filters are very effective at trapping small particles.
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Clean Water Return: Once the water has been filtered, it's clean and free of debris. It's then pushed back into the pool through return jets, typically located on the pool walls. These jets also help circulate the water, ensuring even distribution of chemicals and temperature.
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Backwashing (for Sand and DE Filters): Over time, the filter media (sand or DE) becomes clogged with debris. Backwashing reverses the flow of water to flush out the accumulated dirt and debris. The dirty water is then discharged through a waste line. Cartridge filters need manual cleaning; you remove the cartridge and hose it down.
In summary, the process is a continuous loop: pool -> skimmer/main drain -> pump -> filter -> return jets -> pool.
