How to Change the Sand in Your Sand Pool Filter

The great thing about a sand pool filter is that you only need to change the sand every five to seven years. However, that’s probably enough time for you to forget how to make the change. Here’s a quick refresher.

Materials You’ll Need:

• Pool Filter Sand – use a high rated number like 20 silica sand
• Duct Tape
• Lubricant
• A screwdriver or drill
• A shop vacuum or bucket
• Face mask (optional)

Once you have the materials you’ll need on hand, follow these steps to change the sand in your pool filter:

1. Turn off the pool pump

2. Remove the drain cap

The cap is on the bottom of the tank. First loosen the cap to release some of the pressure from the tank and then fully drain the tank by removing the cap altogether.

3. Disconnect the multiport valve

Unscrew the unions that connect the waste, pump, and return pipes to their respective ports.

4. Take off the collar

Also called the flange clamp, the collar is what holds the filter on the tank. Use a screwdriver to remove the screws that holds the collar in place. Make sure you don’t lose the protective caps that cover the screws.

5. Take off the valve

It’s important to gently twist the multiport valve off the stand pipe inside the tank. There are lateral pipes at the bottom of the tank that you risk damaging when you pull the multiport valve too aggressively.

These laterals are attached to the bottom of the standpipe within your pool sand filter. Replacing a broken lateral in your sand filter means that you’ll have to first remove the multiport valve on the top of your filter.

6. Tape the stand pipe closed

Use your duct tape to tape the stand pipe shut to prevent any sand from getting in. Sand in the stand pipe means you’ll have sand in your pool.

7. Remove the sand

Use your bucket or shop vac (it goes much faster if you have a shop vac) to remove the sand. Be careful to not damage the lateral pipes.

8. Rinse

Get rid of any remaining sand by rinsing the inside of the tank with your garden hose. This is also a good chance to double check that your lateral pipes are still in good condition.

9. Plug the tank

Reattach the drain cap on the bottom of your filter tank.

10. Fill the tank halfway with water

11. Add the sand

Refer to your filter’s manual for the appropriate amount of sand to add. The quickest way to add the sand is to balance it above the top of the filter tank and then make a small slit or opening in the bag.

12. Check the o-ring and replace it if necessary

The o-ring is located on the bottom of your multiport valve. Since you don’t replace the sand in your filter often this is a good opportunity to check the condition of the o-ring and replace it if necessary. To do this you should first lubricate the new o-ring and place it on the underside of the valve.

13. Replace the stand pipe

Be sure to remove the duct tape you added to the stand pipe in step six above.

14. Slip the multiport valve back onto the stand pipe

15. Reattach the clamp

16. Reconnect the pipes to the multiport valve

17. Backwash

Be sure that the pool pump is off. Roll out your line so that the waste water will be dumped in a suitable location. Turn the filter on to backwash for two minutes. Keep an eye on your sight glass, which shows water coming out of the filter. When it runs clear you know you’ve cleared the debris out of your filter.

18. Rinse

Turn from the backwash setting to the rinse setting. Rinse for one minute.

19. Turn the pump on

This is the last step! Turn the pump back to the filter setting and turn the pump on.

A Tip on Pressure

The pressure that your pressure gauge reads while filtering the water should be at a normal pressure level. If it gets to 10 PSI or higher then you should backwash.

Hopefully this guide has jogged your memory (or taught you something new). Either way you’re now ready to replace the sand in your filter.