First let me say that I'm a semi-rookie when it comes to pools. I bought my house 1 yr ago & it came with a pool. I've got the water chemistry aspect of things down pretty good, but I'm not the best at troubleshooting mechanical issues...which brings me here
The issue i'm having is this: when my pump kicks on, the water level in my pool DRASTICALLY drops (like 1" in a little over an hour). The water level only drops when the pump is turned on. This just started happening this past Sunday (Aug 2nd). It's so bad that i'm having to decrease the time I run my pump to ~2 hours per day, and then fill the pool back up with the water hose every day (not looking forward to next month's water bill). From reading some other threads on here, i'm thinking I may have an underground pipe leak on the suction-side (i really hope not). Another possibility I thought of is that maybe my multi-port valve is broken and the water is going out my waste/backwash line. Something else I noticed is that when my Polaris is OFF, there is a small stream of water leaking from what appears to be the impeller area of the Polaris booster pump. When the Polaris booster pump is ON, the leak stops.
Some info about my pool & pump/filter arrangement. Pool was built in 1997, it's 15,000 gal, gunite IG. I have 3 lines that go to my pump (each line has its own valve...like they type of valve you'd see on a garden hose spigot); #1 a "main drain" in the deep end, #2 a line from the skimmer baskets, and #3 a "vacuum line" which comes from a small plastic pipe that protrudes about 2-3" into the side of the pool & it's ~6-8" below the waterline (I hook my vacuum hose up to this). Unfortunately I don't know the make, model, or capacity of my sand filter, pump, & booster pump for the Polaris 380. I do know that both pumps are single speed pumps. I can take pics of all this when I get home from work today. And I think the previous owner left me a folder with information about the pool...I'll find that; hopefully it has specs in it on the equipment.
ANY help, suggestions, or comments are greatly appreciated!! Thank you in advance!!