I have just bought a single fill washing machine and modified the water input
by using a switched 3/4 inch switched tap splitter.
I have to turn the hot water on by hand, and when it's full turn it off and turn the cold on.---
But I have noticed when it is filling it automatically switches from the left hand fill in the soap dispenser, to the middle one. Meaning the two solenoids (hot and cold) are still fitted and working.
All they've done is blank off the hot fitting and siamesed the two pipes internally.
So all that would be need to make it dual fill would be
One pipe fitting and two bits of hose.

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