This is what I read from another reader in 2005. His name is John D, seems to be helpful. I will also try this and hope to clean my machine ..
this is often due to a buildup of soap and softener causing sludge, especially if you use low-temperature washes a lot.
Give it a HOT! wash, with NO powder, and some cotton towels. If you see them frothing up you will know it is dissolving soap powder that has built up.
Do it again.
When the hot water stops being soapy, you have got it clean.
This is a maintenence wash and you might find it mentioned in the machine instructions.
Pull out the soap powder drawer, and give it, and the slot, a scrub with hot water to remove any congealed softener and powder. If you find black mildew in there, spray and scrub with a kitchen clener that has bleach in it. the bleach kills the mildew, and then it comes off easier. I use a nylon washing-up brush (but personally, I have now taken to throwing the scoop of powder in through the porthole rather than into the drawer).
Also check the instructions for your powder and make sure you are not adding too much.
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