Water coming out backwash hose

Jun 26, 2007
ok the pool finally looks a little better. new problem though, when i have the sand filter on filter a little bit of continous water is coming out the backwash/waste hose, any idea why? we've had the filter on non-stop for about a week trying to get a green water issue resolved and was told we had to leave the filter on until its clear.


TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
Silver Spring, MD
It sounds like the main valve is leaking a little. Double check that the main valve is fully into the filter position. If it already is and you have a multiway valve it is probably the spider gasket, if it is a push pull valve it will be one of the O rings. Either way it is probably not too serious, the right replacement part and a little work and it will be fine.


LifeTime Supporter
Mar 31, 2007
If your valve is like mine (push handle down to change position) I sometimes have to make sure I pull up on the handle when I put it in filter or mine will leak a bit, may try that.
Jun 26, 2007
ok so now the filter is leaking out the backwash in all positions. I had to turn off the filter and put it in closed position cause our backwash hose is too short and the pool was emptying into our neighbors yard. When it was on it was running between 5-10psi at the most. What could cause the water to leak out the backwash in the filter and closed positions? and still do it when turned off? i have the multi-port round valve system where you turn the valve 360 degrees circle to get to your setting.


TFP Expert
LifeTime Supporter
Mar 29, 2007
Coastalish 'down easter'
TB, want the good news first? - it's probably only the 'spider gasket' that Lion spoke of - turn the system off and remove the 6 -10 screws & nuts that hold it together (keep track of the screws and nuts!! put them in a cup so you don't lose any!!). Pull off the top of the multiport and look inside. What I suspect you'll see is that the gasket is warped (the warpage can be cause either by leaving the unit tight on the gasket over the winter or by lubing it with a petroleum based product! :shock: ) A new gasket will fix this problem.

Bad news - it's possible that the 'tracks' that the gasket fits into may be cracked, broken or warped :( . If that's the case, you'll need to replace the whole multiport to correct the leaks :cry:

I will hope that you realize that changing multiport positions while it's under pressure (i.e. the pump is running) will trash the gasket or unit VERY quickly!!

Hope it's nothing too serious, and good luck with it!! :)