Of couse, turn off water to machine. Remove hoses. Then had to open unit - easiest by popping spring in with flat blade in seam under lid. Screws holding valve are on back of unit at hose inlet, so simply unscrew to remove failed valve. Clamp holding hose onto valve is crimped with pliers to remove. I suggest spending the 50 cents a hardware store for new clamp, as my reattachment of existing clamp onto new value leaked. There are four electrical connectors, so remember order in which you removed them and return to same on new unit.
Reassemble in reverse (hoses, water on) and your all set.
Pretty easy: I figure it would be about $200 for service guy and part. My cost: $30 and 30 minutes