Sand replacement is a straightforward task you can do yourself in about an hour

Hayward sand filters trap dirt and debris as water circulates through your pool. Over time — usually every three to five years, depending on how much you use the pool — the sand becomes clogged and stops filtering effectively. When this happens, you drain the filter tank, remove the old sand, and pour in new pool-grade sand. The whole job requires no special tools beyond what most homeowners have, and the sand itself costs between $30 and $60 per bag.

The process is the same whether you have a Hayward ProSeries, S200, S244, or other Hayward model: you turn off the pump, open the filter, scoop out the old sand, rinse the tank, add new sand in layers, and reassemble. The main difference between models is the size of the tank, which determines how many bags of sand you need.

Key Takeaways

  • Turn off the pump and close the multiport valve before opening the filter tank to prevent water from spraying out.
  • You need pool-grade sand only — never use play sand, silica sand, or any other type, as it will damage the filter.
  • Add sand in three layers, rinsing between each layer, so it settles evenly and the filter works properly.
  • The filter will not work correctly if you skip the rinse cycles after reassembly, so run the pump on the rinse setting for two to three minutes before switching back to filter mode.

Gather the right materials before you start

You will need pool-grade sand — this is the only type that works in a Hayward filter. The sand is specially sized to trap particles while letting water pass through. Bags are usually labeled "pool filter sand" or "#20 silica sand for pools" and come in 50-pound bags. Check your filter manual or the Hayward website to find the exact capacity of your model; most residential filters need two to four bags.

You will also need a bucket, a garden hose with water pressure, and a wet/dry shop vacuum (optional but helpful for cleaning the tank). Wear old clothes and have towels nearby — this job gets wet and sandy. If your filter has a drain plug at the bottom, place a bucket underneath before opening it.

Turn off the pump and depressurize the filter

Switch off the pool pump at the breaker or control panel. Wait five minutes for the system to depressurize — you will hear a slight hiss as air escapes. This step prevents water from spraying out when you open the filter.

Next, turn the multiport valve (the dial on top of the filter) to the "Closed" position. On some Hayward models, this setting is labeled "Off." If your filter has a pressure relief valve on the side, open it by turning the handle counterclockwise until water stops dripping out. This ensures all pressure is released before you open the tank.

Open the filter tank and remove the old sand

Most Hayward filters have a large clamp band around the middle of the tank. Loosen the bolts on this band by turning them counterclockwise with a wrench — usually four to six bolts. Once loose, lift the top of the tank straight up and set it aside on a flat surface. Be careful: the tank is heavy, and there may be water pooled on top.

Inside, you will see the sand and the internal pipe (called the standpipe) running down the center. Use a bucket or shop vacuum to remove the old sand. If you use a vacuum, work slowly to avoid clogging it. Once the sand is out, rinse the inside of the tank thoroughly with a garden hose to remove any remaining sand or debris. Pay special attention to the standpipe and the bottom of the tank.

Add new sand in three layers with rinsing between each

Before you add sand, make sure the standpipe is in place and find. Pour the first layer of sand — about one-third of the total amount — into the tank around the standpipe. Add water from the garden hose as you pour, so the sand settles evenly and does not create air pockets. The water should reach about halfway up the first layer of sand.

Once the first layer is settled, pour the second layer of sand and add water again. Repeat for the third layer. This layering method ensures the sand compacts properly and filters water evenly. If you pour all the sand at once, it will settle unevenly and create channels where water bypasses the sand entirely.

Reassemble the filter and run the rinse cycle

Place the top of the tank back on the base, making sure the O-ring (rubber gasket) is clean and seated properly. Tighten the clamp band bolts evenly in a crisscross pattern — like tightening a car wheel — so the top seals evenly. Do not over-tighten; snug is enough.

Turn the multiport valve to "Rinse" and turn on the pump. Let it run for two to three minutes until the water coming out of the waste line runs clear. This flushes out fine sand particles that would otherwise cloud your pool. Turn off the pump, switch the multiport valve back to "Filter," and turn the pump back on. Your filter is now ready to use.

When to call a professional instead

If the O-ring is cracked or the clamp band bolts will not tighten, the filter needs a repair before you add new sand. If water leaks from the seam after you reassemble, turn off the pump when ready and check that the O-ring is seated and the bolts are tight. If tightening does not stop the leak, the O-ring may be damaged and needs replacement — this is a $20 to $40 part you can install yourself, but if you are not comfortable doing so, a pool service can handle it in under an hour.

If the filter still does not pressure up normally after you run the rinse cycle, or if the pressure gauge reads much higher than before, air may be trapped in the sand or the standpipe may be cracked. Turn off the pump and check that the standpipe is fully seated. If the problem persists, a pool technician can diagnose whether the standpipe needs replacement.

Frequently Asked Questions

How do I know when the sand needs to be replaced?

The pressure gauge on top of the filter will read 8 to 10 pounds higher than normal when the sand is clogged. You can also backwash the filter (run the pump on the "Backwash" setting for two to three minutes) to clean the sand temporarily, but if the pressure stays high after backwashing, the sand has reached the end of its life and needs replacement.

Can I use regular sand from a hardware store instead of pool-grade sand?

No. Play sand, construction sand, and silica sand for other uses are too fine or too coarse and will either clog the filter or let debris pass through. Pool-grade sand is specifically sized to work with Hayward filters. Using the wrong type will damage the filter and cloud your pool water.

What if water leaks from the seam after I reassemble the filter?

Turn off the pump and check that the O-ring is clean and properly seated in the groove. Tighten the clamp band bolts evenly in a crisscross pattern. If water still leaks, the O-ring may be cracked or the tank may be warped. You can replace the O-ring yourself (it costs $20 to $40), or call a pool service if you prefer not to.

Do I need to backwash the filter before I replace the sand?

No. Backwashing cleans the sand temporarily but does not remove it. You will drain and open the filter to replace the sand, so backwashing first is not necessary. If the filter is very clogged, backwashing may make it easier to see inside the tank, but it is optional.

How long does it take to replace the sand?

The job usually takes 45 minutes to an hour, depending on how quickly the old sand drains and how many bags you need to add. Most of the time is spent scooping sand and waiting for it to settle between layers. If you have a shop vacuum, cleanup is faster.