When it rains it pours. Along with all of my other issues as of late, my top off system failed last night, and pumped about 6 gallons of RO/DI water into my sump. Luckily, I was home and noticed. I quickly shut down the return pump and grabbed my refractometer. The water in the tank was only down to 1.023 (that was a relief), the water in the last chamber of the sump was near 0. All other sump chambers were lingering around that same 1.023. I drained all of the water from the last 2 sump chambers to my top off tank, mixed in enough salt to get it to aroun 1.027 or so, let it aerate for a couple of hours and pumped it back into my sump. All is well (except my top of kit). I think the relay switch failed, as it began buzzing a few days ago. I was told by the company that the switch was just chirping, and that this should no affect the system. Oops. They had already agreed to send me a new one at half price, as the warranty was passed. Not bad customer service I guess.