Of course overflows sometimes happen. There are several potential causes for any washing machine to overflow. A common fault in that regard is one of the water valves hanging open / failing to close ... but your replacement should minimize the possibility (other than the odds of a manufacturing defect in the new part or a bit of debris in the water supply getting past the protective screens). Fix the problem at hand, don't worry so much about other things that could happen. :-) However, do make sure the valve is the problem before ordering the part. Test the solenoids for continuity with a multimeter, and confirm 120v at the solenoids when they should be on. Could also be a broken/shorted wire, temp switch problem, or timer problem.

Thank you for the quick response! There is water getting into the machine. You can plainly see that through the front-loading 'window'. When we put it on hot water vs. cold water, there seems to be more water flow on the hot and less water flow when we put it on cold. Yes by external valves I mean the where the hoses connect to the water supply. They were old so we decided to replace them, hoping it might solve the problem. We checked the debris screens and they are clean. It's weird. I'll turn the wash on and it seems to be working fine then when I go to check on it there's an NF error when it goes through the rinse cycle. I press start again and it continues through the cycle and seems to fill up fine. Any other recommendations? I hope I've described the problem well enough, let me know if you have any other things I can trouble shoot. Thank You!

Thanks, Asolo, Calliope, and Murphy. I live out in the country, on 31 acres, my property surrounded mostly by woods and fields. We used to make tofu commercially here, and our water had to be checked regularly. It always received excellent reports. Granted, that was in the 1970s and 80s, but as far as I can tell nothing much has changed insofar as my property and the neighbors' properties are concerned. Perhaps my ignorance is showing, but there are things about this situation that still puzzle me. The hot water is one of them. Yes, the sediment may have settled out in the hot water heater tank, but I would think 20 years worth of sediment would have caused a problem by now. Maybe not, but I still wonder why the problem is limited to the laundry water. We've never had a problem with water flow in the shower--and for many years five clean people lived here. Ditto the kitchen and two bathroom sinks and the dishwasher. I've never ever seen any kind of particulate in our drinking water, and believe me, I would have noticed. And any visible impurity would have been immediately apparent when we had the tofu business--tofu being a pure white product. I'll put in a call to the guys who installed the pump, and talk filters.......

You probably better off finding something similar to that locally. When I was building my house in 2002, we imported all the vanities from Spain, they came as a complete package, vanity, tops, mirror, lights, sinks, and all the plumbing fixtures, my plumber said right from the get-go use faucets that you can get locally because if something is missing or need replacement down the road it will be a hassle getting them plus they use the metric system and so is AU... unless they import this brand of fixtures to the US and modify to our standards. I end up using all the fixtures made by Grohe manufacturer and I would never use anything else, 19-yrs in my house and not a single issue.