How to Clean a Sand Filter
Turn off the Pool Pump
Any time maintenance is needed for the filter make sure the pump is turned off. This will prevent damage to the pumping as well as the multiport valve.
Backwash the Sand Filter
The multiport valve on the filter controls the flow of water through the pool system. When the pool system is being used normally, the multiport valve is set to “filter”. This directs water from the pool pump, through the filter and out the “return” port, and then back into the pool.
After making sure the pump is turned off, set the multiport valve to “backwash”. When set to this position the flow of water will reverse. Instead of entering the sand filter from the top of the unit the water will enter from the bottom. In addition, when set to “backwash” the water will be sent out the filter’s “waste” port, so the dirty water can leave the pool system.
Once the multiport valve is set to “backwash”, attach a backwash hose to the “waste” port. This will allow the dirty water coming from the filter to be removed from the pool system and drained into a drainage point like a sewer and storm drain.
Ensure that the multiport valve is set to “backwash” and the backwash hose is attached to the “waste” port. Then turn the pump back on and let it run for about three to five minutes, this will backwash the sand filter. Monitor the sight glass on the multiport valve during backwash. When the water in the sight glass changes from cloudy to clear, turn the pump off once again.
Rinse the Sand Filter
Following backwashing the filter, turn the multiport valve and set it to “rinse”. Rinsing the sand filter is an essential part of the process since the sand has moved around during the backwash and needs to be reset. Also, the filter has backwash and sediment that need to be removed so it is not release back into the pool.
With the multiport valve set to “rinse” turn the pump back on and rinse the tank for about 45 seconds (or longer depending on how dirty the filter is). After rinsing the filter, turn the pump off again.
Set Sand Filter for Normal Use
Finally, while the pump is off, turn the multiport valve back to “filter” which is the normal setting. Once the multiport valve is switched back to “filter” turn the pump back on as normal.