The main problem I had was defect impeller in the circulation pump. The upper part had loosened from the base. I glued it back on with epoxy, and the machine worked again for some months until it happened again. I glued it again, and it worked for some weeks. A better glue would have been better. But the real problem is (was?) the quality or method of attaching the two impeller parts together. Since the machine was 12 years old, the replacement punp would cost more than a new machine, so no a new machine is in place. (I also had a problem with the water supply (valve stuck in closed position with handle in open position), and with latch mechanisms in the circulation pump assembly stuck by the o-ring du to poor reassembly after I had opened it. Discovered and fixed.)