I have a Kenmore dishwasher that is about 4 years old. Tremendous soap build up. Dishes won't get clean. Classes filmy. I know I need to check filter but where is it? How do I get it out? Wrong soap? Hard water? Thanks.

If any, the filter is normally up front low above the ground.
Soap build up is normally caused by overdosing soap in reference to the water quality. The harder the water is, the more soap you need. Also the type of soap is important. Best to use are standard dishwasher tablets that have all necessary ingredients build-in already.

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