I have a 4-year-old softening system with a Clack WS1-CS valve. It regenerates about every 2 weeks without a problem. However, between regenerations, water continuously leaks from the Clack valve through the brine tubing into the brine tank, at a rate of about 0.4 gallons per day. By the time the next regeneration is due, there's 5-6 gallons of excess water in the tank. Then it pre-fills for the brining cycle and adds even more water. When all this water is suck out during regeneration, it takes 3 times the normal salt load with it. So I'm using salt at an excessive rate. I assume the problem is a leaky seal somewhere inside the valve. Could it be anything else? Is this something that a homeowner can repair himself?