How To Replace a Lateral in a Pool Sand Filter


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If you are having sand flush back into your pool during normal filtering operation of your sand filter, you may have a broken lateral at the bottom of your filter's standpipe. This guide shows you how to remove and replace a broken lateral. You will note that this procedure is the same as what you have to do to replace the sand in your filter so in this process you may as well replace your sand also.


Step by Step


Step 1

The laterals are attached to the bottom of the standpipe within your pool sand filter. To replace a broken lateral in your sand filter you will have to remove the Multiport Valve on the top of your filter. If your filter was not installed with union connections, you will have to cut the piping to your filter. When you reinstall the filter after replacing lateral, this would be a good time to add unions.

Step 2

Before you start to replace the lateral and change the sand in your filter, be sure to purchase any material or equipment you will need ahead of time. This might include a lateral or two, sand, the O-ring between the valve and the tank, Teflon tape, lubricant, and unions. For the sand use only high rate No. 20 Silica Sand. An example is pictured at left. Check the manufacturer to determine the amount required. This unit (Hayward S180T) uses 3 50 lb bags of sand - 150 lbs total. You can also purchase our superior to sand Click here for our Sand Alternative.

Step 3

Before you start to remove the filter valve, make sure you TURN OFF THE POOL PUMP. For maximum safety turn off the power at the circuit breaker to the pump.

Step 4

Next release the pressure in the filter tank by turning the drain cap at the bottom of the tank a half a turn counter-clockwise. Then remove the cap completely to drain the water out of the tank.

Step 5

Disconnect the waste hose that is attached to the "WASTE" line coming off the Multiport Valve.

Step 6

To remove the Multiport Valve unscrew unions that connect the piping to the "PUMP" and "RETURN" ports. If your filter does not have unions, cut the piping that connects these two ports. Be sure to leave enough room to attach unions later and stagger the cuts so that one union will not be installed on top of the other.

Step 7

Next take off the Multiport Valve flange clamp that holds the filter onto the tank. Screw off both bolts to separate the clamp. Keep track of the vinyl protector caps that are placed over the ends of the screws.

Step 8

With a gentle twisting motion, lift the valve off the pipe inside the tank. If you pull too fast or hard, you risk breaking the lateral pipes at the bottom of the tank.

Step 9

Tape the top of the pipe to prevent sand from entering and clogging the laterals.

Step 10

Remove sand carefully with a plastic cup until you can see the tops of the laterals at the bottom of the tank.

Step 11

Gently pull the pipe and lateral assembly out of the rest of the sand. Then before you pull the assembly out of the tank, carefully rotate the 10 laterals up to the side of the pipe so that they will clear the hole.

Step 12

Lift the pipe and lateral assembly out of the tank.

Step 13

Check each of the laterals for breaks and locate any damaged lateral. If the laterals are badly clogged you may want to soak them in a bucket of cleaning solution.

Step 14

For this model of sand filter, the laterals are clamped together between two plates secured with 5 screws. To take out the damaged lateral(s), remove the 5 screws. Note: In other models, the individual laterals are screwed into the base. These can be removed by gently twisting the lateral counter-clockwise.

Step 15

Work the top plate apart from the bottom plate. You may have to gently pry them apart with a flat screwdriver. Apply easy pressure at each of the gaps around the assembly to work it apart.

Step 16

Pull the top section off the bottom section to free the 10 laterals

Step 17

Lift the broken lateral(s) off of the bottom section.

Step 18

Replace the damaged lateral with a good one. Reseat the lateral with the tab pointing down.

Step 19

Replace the top section and press the two section together

Step 20

Check each of the laterals to make sure that they rotate up and down freely.

Step 21

Replace the 5 screws

Step 22

Check each of the laterals again to make sure that they rotate up and down freely.

Step 23

Wash out the tank with a garden hose.

Step 24

Check the drain cap for cracks and replace it securely.

Step 25

Fill tank about 1/2 way full with water to provide a cushion when the sand is poured in. This will help protect the laterals.

Step 26

Next you will be replacing the pipe and lateral assembly back inside the tank. Make sure the 10 laterals are rotated up. Place the pipe and lateral assembly inside the tank.

Step 27

After the lateral assembly is inside, carefully rotate the 10 laterals 90 degrees in their down position.

Step 28

Make sure the pipe is centered in the opening. Tape the top of the pipe to prevent sand from entering and clogging the laterals.

Step 29

The sand filter package came with a cardboard sand shield. If you still have this shield, place this over the pipe and within the opening. If not, you will have to take more care that the pipe remains centered when you pour in the sand.

Step 30

Pour sand carefully into the pool sand filter until laterals are fully covered. For this unit 3 bags should leave at least 6" space between the top of the sand and the top of the filter. Level sand as you pour and make sure the center pipe remains centered in the opening. Be careful when leveling the sand that you do not lift the pipe and lateral assemble up off the bottom of the tank. You will not be able to push the pipe back down without causing the laterals to rotate up.

Step 31

Remove the O-rind on the bottom of the Multiport valve and check it for wear. Since you only do this every 5-7 years, it's probably a good idea to replace this O-ring now. Lightly lubricate the O-ring with a silicon lubricant and place it on the underside of the valve.

Step 32

Remove tape from top of pipe. Slip the Multiport control valve onto the central pipe - check the O-ring to ensure it is positioned correctly.

Step 33

Install clamp around the tank and valve flange. Tighten multiport valve flange clamp with a screwdriver. Tap around the clamp with the screwdriver handle as you are tightening the clamp to help seat the clamp properly. Place vinyl protector caps over the ends of the screws.

Step 34

Reconnect the two unions to the "PUMP" and "RETURN" ports. If you did not have unions, add unions now or glue the pipes back together with straight couplers.

Step 35

With the pump OFF, depress the multiport valve handle fully and turn it to the "BACKWASH" position. Make sure that your waste line is rolled out to where you want to dump the pool waste water.

Step 36

Prime and turn ON the pool pump. Be sure that you have at least one suction and all discharge lines open.

Step 37

Run the pool pump for 2 minutes after you have a steady flow of water out the waste line (after the pump is fully primed). This will flush all the impurities or fine sand particles out of the sand media.

Step 38

Turn the pool pump OFF and turn the valve handle to "RINSE".

Step 39

Turn the pump back ON and run until the water in the sight glass is clear. This should take no more than 1 minute.

Step 40

Turn the pool pump OFF and turn the valve handle to "FILTER".

Step 41

Turn the pool pump ON. This is the normal operating mode for your filter. Note the pressure gauge reading. This is your clean sand filter pressure. When it increases to an additional 10 psi, it's time to backwash your filter.


(1 to 40 of 60)

 Posted: 9/14/2021 

can't get the laterals off will not unscrew can't get them to turn counter clock wise what can i do to get them off.

InyoPools Product Specialist  Posted: 9/14/2021 

What is the make and model or model number of the filter? We need to be able to identify it to figure out how then to disassemble it.

 Posted: 9/15/2021 

can't get the laterals off will not unscrew can't get them to turn counter clock wise what can i do to get them off. the last answer was wrong it is a aqua tools filter AT3118

InyoPools Product Specialist  Posted: 9/15/2021 

The laterals for that filter, Part # - 24600-0003 say there are two locking tabs, pictures also show the tabs. From the product description " It has 2 locking tabs near one end to lock into the hub also has 2 more locking tabs near the middle no numbers are molded into the lateral, but on the side with no slots, “this side up” and “made in Canada” are molded"

 Posted: 9/15/2021 

So how do i get them off ? I should be able to turn it once and pull it off right.

InyoPools Product Specialist  Posted: 9/16/2021 

By comparing the tab holes in the hub and the lateral tabs, it looks like a half turn and pulls out should be the way.

 Posted: 9/16/2021 

If i can get them to turn that"s the next thing thank you

 Posted: 7/9/2020 

no one shows what a broken lateral can look like..inwas surprised..mine was one tiny slit in one of the 8; i have a pic for you to use if you email me..i will email the pic back..i think what a broken lateral can look like is most important tonthis thread.

InyoPools Product Specialist  Posted: 10/20/2020 

Awesome, thank you. Send an example of the cracked lateral to ATTN: Matt.

 Posted: 10/9/2018 

How do change laterals on a Hayward 240 with side input. Looks like plate holding laterals is fixed with a tan on the center tube. Is there a trick to moving the retaining plate? The laterals will not unscrew, too tight. Suggestion?

InyoPools Product Specialist  Posted: 10/10/2018 

Hello Dow - are you referring to key 16 on this Hayward S200 & S240 parts listing?

 Posted: 5/15/2018 

You can vacuum the sand back into the filter.

Anonymous  Posted: 5/14/2018 

My son replaced the lateral system yesterday. There is sand on the bottom of the pool. How do we take it up?

InyoPools Product Specialist  Posted: 8/22/2016 

Joanibologna - Some sand contains very fine sand in the mix that may get thru the laterals. If that is the issue, vacuum the fine sand off the floor and send it out the waste line. If that isn't the issue, you may have to take the sand out again to check the laterals, the lateral hub and the standpipe for new breaks. Also, check that the laterals are fully rotated to their 90-degree position. And check your parts list to see if you should have an O-ring at the top of the standpipe.

 Posted: 8/21/2016 

We were getting a lot of sand in our pool so we had our laterals replaced and new sand filled, as well as a brand new standpipe and spider gasket. Our pool is still spitting tons of sand in the pool. The guy said we'd notice some sand until it all settled but this seems excessive. What could be the problem?

InyoPools Product Specialist  Posted: 7/23/2016 

ACS - Thank you very much for your observation !

 Posted: 7/21/2016 

After cleaning, inspecting putting in new sand etc. my filter was blowing sand into the pool when it first came on. Everyone said it had to be the laterals or the spidergasket. No one told me it could be that one of the laterals got pushed out of alignment while filling the filter with sand. If they are not at 90 degrees there is an opening between the laterals and the center pipe. One was knocked loose when I put the sand in even though I thought I was very careful. When I replaced it the second time I made sure to put sand underneath them by hand. With the tank half full of water the sand still piled up so I made sure to distribute it gently. It seems to be fine now.

InyoPools Product Specialist  Posted: 6/6/2016 

tabimichelle - Did you leave at least a 6" space between the top of the sand and the top of the tank? Also, some standpipes have an O-ring where they connect with the MPV. Is that in place? Lastly, you might have to remove the sand again to look at the laterals and their hub to see if you have any new damage.

 Posted: 6/4/2016 

I replaced my standpipe and laterals near the end of last season. Had to replace the valve this seasonal hooked our pipes up backwards (for about 3 weeks) #insertfaceinpalm We have since correctED the problem and nearly have the algea infested pool clear but after I vacuum to waste > backwash > rinse my sight glass fills with sand on rinse and won't clear and then loads the pool with sand when I cycle back to filter. Sand only enters the pool after that process. My laterals and pipe look fine. Any other ideas?

InyoPools Product Specialist  Posted: 6/2/2016 

Clint - I'm not sure what the problem is here. If the pool is getting cleaner and is in filter mode, the dirt has to be going into the sand. What is it that tells you that the sand does not need to be backwashed?

 Posted: 5/31/2016 

I have had my pool for 8 or 9 years. It has been up and running for a couple days. It's pretty dirty but getting better. My concern is that it hasn't needed backwashed for a couple days. Which is unusual normally when I open it I have to backwash often for several days. Could this be a sand filter problem?.

 Posted: 8/24/2015 

I had the main bottom drain closed I'm thinking maybe I was just trying to suck up too much sand at one time I'll try a little less
Thank you


InyoPools Product Specialist  Posted: 8/24/2015 

Waterman - Try boosting your suction pressure by closing down the main drain suction line.

 Posted: 8/24/2015 

I wound up with an awfull a lot of sand in my pool when I go to vacuum it to waste all it does is clog up my vacuum hose am I not getting the right amount of suction and if not why

InyoPools Product Specialist  Posted: 7/15/2015 

helpdebbie - Check the spider gasket in your multiport valve to make sure it is not damaged, but it sounds like you have a broken lateral or standpipe.

 Posted: 7/13/2015 

We have never owned a pool. It appears we hooked up the piping backwards. Now that we switched the piping we backwashed, rinsed and filter...we just get sand blowing straight into the pool...lots of it! we have backwashed again and again, rinsed again and runs clear...but as soon as we filter...sand continues to shoot into the pool? Help.


InyoPools Product Specialist  Posted: 6/15/2015 

Krystle - It's uncommon, but the standpipe does get damaged in operation or while changing the sand. If you have a " Hayward Pro Top Mount Sand Filter 18”,21”,22”,23”,24”,27" like the one shown in this guide, the standpipe can only be purchase by buying the whole "Lateral Assembly with Pipe" [#6] in the parts list. Select the Lateral Assembly that matches your filter tank size.

 Posted: 6/14/2015 

Hi! While I was changing the sand in our hayward sand filter the standpipe had broken off from the lateral attachment near the bottom, and the broken jagged piece still attached/glued in the lateral assembly, coukdnt get it out. Do I need to get new lateral assembly and stand pipe or is this a common occurrence? Help!! We are pools

InyoPools Product Specialist  Posted: 6/9/2015 

Bettboo2008 - Enter the make and model for your filter [example Hayward Pro 18"] in our search field, then select the parts list.

 Posted: 6/8/2015 

Were do i find the housing unit for the lateral filter arms? Mine is completely broke and need a new one

InyoPools Product Specialist  Posted: 5/26/2015 

25K gallons - Yes, the vertical stand pipe will crack occasionally and have to be replaced.

 Posted: 5/25/2015 

Thanks for your instructions, they were extremely helpful. Although we were getting a little sand in the pool, the lateral seemed to be the only recommendation to fix. Once removed the laterals seemed ok but the stand-pipe had a crack across the bottom of it. Have you ever come across this? I replaced the entire lateral w/stand pipe and am now beginning to finish opening the pool. I'll report how things turned out in a day or two. Thanks Again, 25K gallons

InyoPools Product Specialist  Posted: 7/8/2014 

voyage1 - Make sure you have at least 6" of space between the top of the sand and the top of the tank. Next check the spider gasket in your multiport valve to make sure it isn't damaged. Also, new sand sometimes has some fine sand that gets through the filter. Try vacuuming the sand off the pool floor and putting it out the waste port. Then backwash and rinse the sand 2-3 times to get any other fine sand out of the sand in the filter. And finally the vertical pipe on the lateral assembly sometimes cracks. If you don't want to take all the sand out again, at least take the multiport valve off the pipe and inspect the top of the pipe and the bottom of the multiport valve.

 Posted: 7/7/2014 

My laterals and Hayward sand filter are just like in the photos. I decided to check my laterals after having sand shooting into my pool all the time. Just in case, I ordered a new Hayward center pipe and lateral assembly to have on hand. Also, I ordered new # 20 silica sand since the sand hasn't been changed since installation in 2006. However, since pulling out the old sand, the existing laterals do not appear to be broken or cracked. Could the old sand eventually wear down where it would make it's way into the pool thru the laterals?

InyoPools Product Specialist  Posted: 6/19/2014 

Trip Davis - It does not matter if the laterals are positioned up or down. The water will get through them either way.

 Posted: 6/19/2014 

My filter froze in last year's cold winter. Started getting sand in pool and took filter apart. Laterals had come loose and I was able to fix it. My question is all the laterals I see online are 360 degrees. The laterals I have are 180 degrees. Are the openings on the laterals suppose to be up or down? I don't know.

InyoPools Product Specialist  Posted: 6/17/2014 

julie - Check the spider gasket in your multiport valve. It may be damaged and allowing water to flow out the wrong ports. See our guide on "How to Replace a Spider Gasket on a Multiport Valve". Remember to turn the pump off each time you change the valve setting.

 Posted: 6/16/2014 

Followed these steps to replace the entire lateral assembly and after the last step there is still water coming out of the waste line...any ideas?

InyoPools Product Specialist  Posted: 4/8/2014 

Jerry - If parts are missing off of the laterals, I would replace them before you fill the filter tank with new sand. Here's a link to the parts list: Jacuzzi Laser Sand Filter.

 Posted: 4/7/2014 

I have a Jacuzzi lazer filter system. I have it pulled apart but the yoke at the bottom tht hops the snap in laterals x 8. The yoke will not come out of the filter. I can pull it to the top but it is just shy of allowing me to pull it out. I have got all of the laterals out but a few of the do not have the small tab on the bottom. They snap back in pretty tight without the tab, what should I do, run with it or try to replace the laterals ?
Thank you for excellent information. Does your store carry the lateral?