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Parts for Whirlpool KHWS01PWH0 Washer - AppliancePartsPros.com

[COLOR="Blue"]My front load washer fills with water when not in use. I shut off the water supply and remove the hoses to see if the valve is leaking. There is no leaks at the valve. This eliminates the inlet valve on the washer I assume.[/COLOR]
I am not sure how you tested this as you would not see a leak.
You said the washer fills with water so it depends how much water.
A water valve leak could fill it but I doubt a drain hose problem would do this as once the trap in the house plumbing empties the filling should stop.

[COLOR="Blue"]I can only guess that rinse water in the drain hose is leaking past drain motor back into drum! Am I correct? and if so what would fix this problem?[/COLOR]
It could be siphoning back into the unit.
To double check this, turn off the water taps if the filling stops then it is the water valve.
Pull the drain hose up so that it is not down in the plumbing trap, if the filling stops then it is the drain system. Most likely the anti siphon ball, could be it is just dirty.
See the Pump And Motor Parts section, if you click on a parts description or picture a new page will open with additional info about that part.
This would also be a good time to clean out the filter (Item 14).

Note that the drain hose should not go all the way down to the trap. Also there should be room around it in the stand pipe so air can pass by it.
See the Operators Manual, it should have some install info.
Here it is just in case you do not have it.
http://www.whirlpool.com/digita...0Guide%20-%208182400.pdf