When you start up your pool for the first time or at the beginning of the swimming season, you should have noted your clean reading on the pressure gauge. When the pressure gauge reading is 8 to 10 lbs. per square inch (psi) higher than the clean reading, you need to backwash the sand filter to remove the dirt particles and refresh the sand. If you don't backwash the filter, the sand will not filter the tiny dirt particles out of the pool water.
Multiport Valve Handle
Turn off the pool filter. Lift up on the multiport handle. Turn the handle to "Backwash." Roll out the backwash hose on the bottom of the pump.
Turn on the pump. Run for two to three minutes or until the water in the sight glass (if you have one) runs clear. Turn off the pump.
Turn the multiport handle to "Rinse." Turn on the filter pump. Run for one minute or until the water is clear passing through the sight glass. Turn off the pump.
Move the handle to "Filter." Turn on the pump. Roll up the backwash hose.
Slide Valve Handle
Turn off the pool filter. Lift up on the slide handle and pull up until it doesn't move any higher. This is the backwash position on a slide handle. Roll out the backwash hose on the bottom of the pump.
Turn on the pump. Run for two to three minutes or until the water in the sight glass (if you have one) runs clear. Turn off the pump.
Push the handle back down until it clicks and locks into place. This location is "Filter" on the slide handle.