Water Discharges To Discharge Hose While In Filter Position

by Brian
(Galloway, NJ)

When I run the filter in the filter position, a small amount of water continues to run out of the discharge hose. Normally when it was in the filter position there was no flow to the discharge.

After I vacuum and the pool is clean, I run the filter. Within a few hours of running the filter there is a small amount of sand/dirt that accumulates.

This is within a short period of time. I replaced the lateral valve assembly w/ center pipe since the pipe in my original one broke.

I have a Hayward s180t1580.

Any help is appreciated.

Thanks for the question Brian

You want to check the obvious things first. Be sure the gasket around the pump lid is clean, not split or cracked, and free of debris. Be sure you're bleeding the air out of the system.

Also you'll want to check the spider gasket in the Multiport valve. These gaskets can get old, cracked, or worn.

Don't lube it with a petroleum based product. Use a good lube such as:


Jack's Lube

Pool Filter Multiport Valve Gasket Sealant

Pool Filter O-Ring Gasket Valve Lube Sealant 1.75 oz. bottle

Don't glue the gasket in place. When it comes time to clean them or replace them, you're going to need to carve it out and run the risk of chipping or breaking the surrounding plastic.

Here's a link to the spider gasket picture:

Water Coming Out Backwash Hose During Filtration

Here's another good link:

Replaced Lateral But Still Sand In Pool

Is your sand new? This will cause debris to go back into the pool, which is normal. New sand is loaded with dirt. It's this dirt that goes back into the pool. As the sand gets used it will settle and you'll see less dirt. If this is a problem, you can always vacuum to WASTE. This bypasses the filter so the dirt doesn't get caught in the sand again.

I had to vacuum the Y pool for a couple of weeks until the new sand settled in.

Check what's known as "freeboard". This is the measurement of the top of the sand to the top of the filter. You can check with the filter manufacturer to see what the correct amount of sand your filter uses.

Be sure the water level is between 1/3 - 1/2 up from the bottom of the skimmer. Water level below the skimmer and your system will draw in air.

Another thing that might contribute to sand going back into the pool is not doing a RINSE after back washing.

You may have accidentally dumped the sand into the filter without covering the stand pipe coming up from the bottom middle of the filter. The sand might stop going back into the pool as it is consumed.

Here are some other things you can consider:

1. Broken lateral and/or diffuser

2. Channeling

3. New sand

4. Old sand

5. Not doing the RINSE after back washing

6. Lateral impacted with sand and/or debris

7. Not having the correct measurement of freeboard

Sand, with good maintenance, can normally last anywhere from 5 - 10 years.

To post a reply, or if you have a similar question, you can see your post on the Q&A page in the "Sand Filters" category.

Check back to this post for updates or answers.

If you need immediate assistance (within 24 hrs) or for emergency personal assistance, you can make a donation of your choice and I'll answer your questions by phone.

Contact Me


Hope this helps and have a great Summer.


Click here to read or post comments

Return to Pool Sand Filter Maintenance.

swimming pool care, basic pool care, above ground pool maintenance, inground, salt water

Click Here To Learn How This eBook Can Save You TONS Of Time & Money

Click Here To Learn The Best Way To Clear Up Your Pool 

Recent Articles

  1. Our Swimming Pool Water Is Slightly Milky? Problems..

    Please can anyone tell us why we have a slightly milky look to our swimming pool water? How can we get that chrystal clear water? When we do a test (we

    Read More

  2. White Slimy Film On The Bottom Of Pool

    the water was crystal clear but upon skimming the top we noticed a white slimy film completely covering the pool liner.

    Read More

  3. High Cynaric Acid

    My pool is a 26,000 gallon above ground vinyl liner. around 7/31/2014 the cya raised to 113

    Read More