That time of year in Southern Ontario to pack up the pool
Every year I remove the sand filter drain cap and let the water drain out. Sand has never come out.
This season I had some issues with the filter and opened it up to check a few things. I was going to run a hose into the filter and skim off any debris. Anyways, the laterals got "disturbed" so I had to empty the filter. While I was in there I replaced broken laterals and replaced the sand as well. When emptying the filter housing I saw no specific part that acted as a filer, plug or strainer to prevent sand from emptying out of the drain. So, I filled the filter with new sand. I replaced the sand only because I was in there and I expected the sand to have never been replaced (15+ years?). It was not a huge expense so that is why I went ahead.
Anyways, I read somewhere that because the sand is wet it pretty much stays in place and that is why it does not come out the drain when the cap is removed.
I closed the pool down this weekend and when I opened the drain cap, sand came flowing out with the water like a mud slide. It would not let up. The sand kept flowing.
I managed to wrap and tie some cloth around the drain neck to allow the water to drain but hold back the sand.
Did I fail to replace something when I changed the sand?
If not, does anyone have ideas why sand is emptying out the drain.