After a period of time, the contaminates in a sand filter start to clog the sand to the point where water flow is significantly diminished and the pressure gauge rises 8 to 10 psi above normal operation readings. To clean out the contaminates, you have to backwash the sand. This guide shows you the steps in backwashing a filter.
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Anonymous Posted: 11/11/2018
I did a dumb thing the other day while vacuuming my pool. Normally I vacuum it on the “waste” setting, but I must have Ben half asleep and vacuumed the entire pool with it on the “backwash setting” what does that mean, and have I done harm to the system or the filter?Reply
Anonymous Posted: 11/11/2018
I did a dumb thing the other day while vacuuming my pool. Normally I vacuum it on the “waste” setting, but I must have Ben half asleep and vacuumed the entire pool with it on the “backwash setting” what does that mean, and have I done harm to the system or the filter?Reply
InyoPools Product Specialist Robert M. Posted: 11/15/2018
Thank you for contacting Inyo. You probably didn't do any significant damage to the filter. However, all of the vacuumed debris went to the bottom of the sand bed instead of the top. This means that when the system is returned to filter and turned on, all of the debris will blow back into the pool.Reply
Matthew Posted: 8/7/2018
Hello Jerry - this issue may not be stemming from your filter but from the pump or plumbing. How is your pressure gauge responding in these situations, is it rising or dropping? Do you see air bubbles in the pump basket causing it to lose prime? If so, then you may have an air leak causing the pressure problems. Is your water green or cloudy? If so, the rise in pressure could be from algae (dead or alive) is quickly clogging the filter causing repeated backwashes.Reply
InyoPools Posted: 7/27/2018
Hello Dean - You'll need to backwash the filters when the filter gauge rises 10 psi over the clean filter PSI. For example, if your filters are 15 PSI when the filter is clean, they'll need to be backwashed when the PSI is 25.Reply
Dean Posted: 7/21/2018
I have 2 36" filters at work. How often should I backwash?Reply
Inyopools Posted: 7/13/2018
Hello Vince - The vacuum to waste feature would serve as your "rinse" setting.Reply
Anonymous Posted: 5/27/2019
Thank youReply
Vince Posted: 6/15/2018
My pool filter valve doesn't have a rinse setting. What can i do when I need to rinse?Reply
Inyopools Posted: 6/8/2018
Hello Nick - No, you do not need to close the return/outlet when backwashing. You can keep those open.Reply
nick Posted: 6/7/2018
When you backwash, do you keep the outlet/water return side to the pool closed or open?Reply
Jerry Posted: 6/5/2018
I have a sand filter.It has new sand and laterals have been cleaned. When you backwash it has very little pressure, after one minute it will almost stop running. What can be wrong with it.Reply
Inyopools Posted: 5/30/2018
Hello Joseph - You shouldn't worry about adding more contaminants to the filter when backwashing. The process of backwashing will flush contaminants out of the filter. If you want to bypass the filter, use a chemical called Floc & Vac and vacuum all the debris directly to waste.Reply
Joseph Lawson Posted: 5/27/2018
I just bought a sand filter for the first time. The manual says it should run around 8 psi. It is running around 10 psi, though. Back washing and rinsing is not making much of a difference. My water is very cloudy because I neglected the pool this winter. I just got the algae under control. My concern is by back washing with the cloudy pool water, am I just adding more contaminates into the sand? Is there an easy way to backwash and rinse with clean water from a source other than the pool?Reply
Inyopools Posted: 5/15/2018
There is a small gasket/o-ring where you thread in the sight glass. That may have gone bad and that is why it is leaking.Reply
Anonymous Posted: 5/14/2018
I have water coming out of sight valve when backswashing, what is wrong?Reply
Inyopools Posted: 4/23/2018
Hello JS - You shouldn't need to close the skimmer when backwashing. The only reason for closing the skimmer would be if you lose so much water that the water level drops below the skimmer when backwashing. If it is a suction style vac, the most common cause of the cleaner not switching ends is lack of suction. This could be caused by a dirty filter, holes in the cleaner hose, or a suction side air leak.Reply
JS Posted: 4/20/2018
There is a shut off valve beneath my skimmer. Do I turn it off (so that water from the pool doesn't flow) before backwashing? Also, my vacuum goes around by itself but it never seems to get to one side of the pool. Is this a problem? Thanks so much!Reply
Anonymous Posted: 3/30/2018
Has no-one installed a backwash tank? We have a 500 litre tank. The tap is about 20 cms from the bottom. Backflush into this and the next morning the suspended stuff has all fallen to the bottom and the clean water can now be put back into the pool with a hose pipe. I'm in South Africa which is a water scarce country but I would think that this would be good practice anywhere in the world.Reply
InyoPools Product Specialist Dennis R. Posted: 8/28/2017
Joel - You generally backwash a filter when the pressure gauge reads 10-12 psi higher than the last time you backwashed it. And you generally change the filter sand ever 5-7 years.Reply
Joel Posted: 8/27/2017
Great video, few question new to the pool world. How often do you run the backwash how often do I change the sand?Reply
InyoPools Product Specialist Dennis R. Posted: 8/7/2017
Anonymous (sand in pool) - You may be seeing the fine sand that is in the new sand. Try backwashing and rinsing a couple of more times to wash out any fine sand. Then check the spider gasket in your MPV. If it is damaged, it may be letting sand into the Filter return when it is in Rinse or Backwash. Then you may have to take the sand out again to check the lateral hub and standpipe for creaks.Reply
Anonymous Posted: 8/6/2017
I have a Hayward sand filter and I'm getting sand going back to the pool! I have taken the sand and the laterals out to make sure there there's any damage and found no damages. I put everything back and started again but still have sand going into the pool. I am at my wits at help will be a greatReply
InyoPools Product Specialist Dennis R. Posted: 8/1/2017
Gemo - Try backwashing and rinsing a couple of more time to see if that clears up your sand issue. If not, you may have to remove the sand to check the laterals, the later hub and the standpipe for cracks or other damage.Reply
Gemo Posted: 7/31/2017
Just installed a new MPV. When i rinse after backwash, a seemingly large amount of sand rushes into the glass sight and the waste line. When i switch back to the filter position some sand discharges into the pool. Did i potentially mess up the install? I know the Stem popped off when i removed the old MPV, but i was hoping we would just discharge any sand that got in and then all would be well.Reply
InyoPools Product Specialist Dennis R. Posted: 7/31/2017
Ga - A cloudy pool is one indication that your filter is not performing well and its sand needs to be replaced. If you don't know when the sand was last replaced, I'd replace the sand. See our guide on "How To Change Sand In a Sand Filter".Reply
Ga Posted: 7/31/2017
Please help I've been to 3 different pool places and no one knows what's wrong with my cloudy (milky) pool water. All my chemicals are testing fine.just bought the house with a SAND pool filter. I'm use to a earth filter is my pool water cloudy cause I need new sand,the pool is probably about 7 yrs. Old and we don't know if they ever changed it. When we opened it the water was green now it's just been cloudy for bout 2 weeks.no one knows why,Reply
InyoPools Product Specialist Dennis R. Posted: 7/20/2017
Anonymous (adding sand after backwash) - No, you do not have to add sand after backwashing. You only lose a very small amount of sand during backwash.Reply
InyoPools Product Specialist Dennis R. Posted: 7/20/2017
Rob - To pump water out of your pool, just set the MPV to "Waste". This mode bypasses the filter. Water flows directly from the pool to the waste port. See our guide on "How a Multiport Valve Operates".Reply
Anonymous Posted: 7/20/2017
You do have to add new sand after backwash?Reply
Rob Posted: 7/20/2017
I have an unground pool with pretty much that same sand filter. We got a lot of rain and I need to pump some water out. What order should I do the backwash, waste and rinse operations?Reply
Susan Posted: 7/12/2017
Thanks you so much for these easy step by step instructions. So clear and easy to use. Prior I was so confused of the exact procedures & now I get it. ??Reply
InyoPools Product Specialist Dennis R. Posted: 7/10/2017
hope - It sounds like your pump is not priming. Make sure your pool level is high enough so that water is flowing into the skimmer. Then see our guide on "How To Prime a Pool Pump".Reply
hope Posted: 7/9/2017
trying to backwash hayward pool filter but when i turn pump on to filter first, there is no water going through jets and in the basket.Reply
InyoPools Product Specialist Dennis R. Posted: 7/3/2017
John - No, you only see water flowing in the sight glass when water is going out the waste line.Reply
john Posted: 7/3/2017
is there suppose to be water in the sight glass all the time mine has noneReply
InyoPools Product Specialist Dennis R. Posted: 6/26/2017
pam - If you have a surge of backwater to the skimmer when you turn off the pump, you may have backpressure building up in the top of your filter tank that impedes water flow as it builds up over time. Check for suction air leaks in the pipe connections at and before the pump. See our guide on "How to Identify and Correct Air Leaks".Reply
Kim Ray Posted: 4/16/2019
I have the same problem. Back wash every 1-2 days to keep flow strong. Any other issues it could be? I dont see significant bubblesReply
InyoPools Product Specialist Robert M. Posted: 4/17/2019
Hello Kim - We'd be glad to assist you. What problem are you having with the pool system?Reply
InyoPools Product Specialist Dennis R. Posted: 6/26/2017
Aj - Use the "Waste" mode to purge extra pool water. Using "Backwash" over a period of time would wash away some of your sand. See our guide on "How a Multiport Valve Operates".Reply