Something inside the valve body went wrong once before: the unit would reach the end of the recharge cycle, but water kept running down the drain. Eventually, a little "call service" light would illuminate. The first few times I could tap the valve body in various ways, something would shake back into place, and the unit would recover. It got to the point, however, when this procedure would no longer work. So I called Culligan repair. The guy took a look and said it would cost $300 to fix. Seeing the shocked look on my face, he immediately stressed that the repair cost was set by corporate. The part he put in looked like it should cost about $5. I told myself, "The next time something major like this happens, I'm ditching this unit and Culligan." This same valve problem began reasserting itself last month, although this may or may not be tied to the "no longer softens" problem.