The Hayward S220T High-Rate sand filter will need to have the sand changed every two to five years depending on the type of usage that the pool receives. The sand filters the tiniest of dirt particles from the pol water during the filtration process. After time, the sand breaks down and will not filter the particles anymore, and it needs to be changed.
Turn off the Hayward S220T pool pump. Remove the drain plug from the bottom of the pool pump to drain out the water.
Disconnect the elbow adapter from the left side of the filter control valve. Disconnect the waste line from the right side and disconnect the return line to the pool on the left side of the filter control valve.
Loosen the flange clamp on top of the S220T pump, which holds the filter control valve in place. The clamp has a U-shaped closure that is popped open. Use a screwdriver to loosen the nut and bolt on the clamp, but do not remove. Remove the top with the O-ring.
Remove the sand from the inside of the pump with the plastic cup. Do not scoop near the center standpipe, but toward the sides of the pump. When you near the bottom of the pump, use the wet and dry vac to remove the remainder of the sand. Be careful not to damage the bottom laterals. Vacuum very carefully to remove any sand inside the fins (laterals).
Replace the drain cap on the bottom of the pump. Put a piece of duct tape over the top of the standpipe to prevent any sand from getting inside. Fill the pump halfway full or to just under the lip of the standpipe. Use the plastic cup to add 250 pounds of #20 silica sand.
Remove the duct tape from the standpipe. Place the O-ring and the filter control valve on the pump with the flange clamp. Snap the "U" closure to lock. Use a screwdriver to tighten the nut and bolt so the flange clamp is tight.
Reconnect the waste line, pool return and elbow adapter to the Hayward S220T filter control valve using the Teflon tape to seal the pipes and prevent leaks. Turn on the pump and inspect the pipes for leaks.