FILTRATION MODE
During the filtration process, unfiltered water enters the system via the inlet manifold and the filtered water exits the system to the field through the outlet manifold. During filtration, the inlet ports are open and the backflush ports are closed. Water flows from top to bottom, across the sand layer.

BACKFLUSH MODE
During backflush, once a pre-set pressure differential or pre-set time is reached, the controller will activate one solenoid (valve and tank) at a time to perform a backflush operation. The inlet port closes and the backflush port opens. This reverses the flow of water in the media filter. Clean water from the other filters now flows into the filter from the bottom through every mushroom with equal pressure, lifting the sand media and freeing the accumulated debris. The debris will be flushed out the top of the filter through the backflush valve into the backflush manifold and to a suitable location. Only one filter should backflush at a time. The water that is backflushing one filter will have passed through the other filter(s) and thus backflushing will be made with clean filtered water.

As debris builds up in the media filter, a pressure loss will develop across the filter. The dirtier the filter becomes, the greater the pressure loss. When the pressure loss reaches a critical limit, the filter is dirty and in need of a backflush. Backflush controllers will sense the pressure loss through hydraulic connections and command a backflush sequence to begin when necessary.

A backflush restriction valve must be installed to prevent the sand from being washed out with the dirty water.

1. Remove the top cover and before adding any media to the filters, inspect the inside of the media filter tank to be certain there are no foreign objects in the tank.
2. Check the mushroom covers and connector pins to be sure they are all in place and secured straight.
3. If possible, fill the tank with water and check for leaks.
4. Fill the tank with the specified amount of sand. The level is indicated on a label that is affixed to the tank exterior. If no label is present, it is recommended to fill the tank to 6” or 7” below where the dome starts.

1. Close all the valves and verify that no pressure remains in the tanks.
2. Open the upper service cover.
3. Open the 3” plug on the lower cover and drain all the water and sand from the filter. Remove the lower cover for faster draining.
4. Carefully rinse the inside of the tank.
5. Check the inside underdrain.
6. Close the 3” plug and install the lower cover (make sure threads are free of sand).
7. Fill the tank with water.
8. Add the new sand.
9. Open all the backflush valves in sequence.

• System Operation
• Installation
• Maintenance
• Troubleshooting