When pump (L) turns on because float switch (M) rises in water in tank (A) during the irrigation cycle, water is sent to the top of filter canister (I) and forced down through the 12 grit sand filter media, where hair, lint, and other debris is trapped in tiny spaces between the sand particles. Water then travels out to a series of irrigation valves for use in the yard.  Larger systems have larger surge tanks and pumps, but act on the same principle of using water as it is produced, instead of storing it.  This keeps the water fresh and oxygenated, which is good for plants.  Our controller starts and stops based on water availability, and our filter is backwashed with fresh water based on accumulated run-time.

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*Filter systems do not come fully assembled, as the plumbing design is different
in each home.  The schematic shown is for illustration purposes only.



To keep the filter clean, when the controller has accumulated a certain (programmable) amount of run time, it begins a self-cleaning cycle after that day's irrigation has been completed.

At the end of the day's irrigation cycle, the controller begins the self-cleaning cycle by opening valve (J) to let city water in and rotating valve (H) to divert the backwash to waste. City water is then rapidly forced up into the 12 grit sand filter media, causing sand particles to rise and separate from each other, releasing the trapped debris. Lighter than the sand, the debris rises to the top and flows out to the waste line.

When the process is over, the valves return to their irrigation position. This cleaning process has been used in agriculture, swimming pools, and water purification for decades.