Quote Originally Posted by millpool
My pool was perfectly filled one week. The next week it was overflowing because of water pressure under the hydrostatic valve. Six days later there was 2.5 feet of water in the deep end. Apparently the valve was stuck in the open position. This has happened twice before. Can anyone recommend how to fix this one and for all? Thanks
If your valve opened while the pool was full of water, then there was more pressure from groundwater outside the pool than from the pool water inside the pool. A very unusual situation. Is the pool located in a hillside or at the bottom of hill? On first glance, it this appears to be a serious engineering issue.