[jyl]

There are two probes at the rear of the tank, that detect when the tank has filled with water. I had cleaned them with a soft cloth as the manual said. So I said screw it and scrubbed the probe tips bright with a green scrubby. I also inserted a valve online with the water supply house to control the incoming pressure. But I think scrubbing the probe tips is likely what fixed it. I will get some deliming agent and delime this machine. I may also order a new probe set for $80, just to have them ready. Some reading - thanks for the link! - suggests those probes are practically a consumable.

Then again, service in my house will be like.retirement for this machine. In commercial use they must run dozens of cycles a day, seven days a week. Here it may run a dozen or two a week.