Stagnant water in a washing machine usually indicates a problem with the machine and you will need to get it repaired. However, once the washing machine has been fixed and is free of stagnant water, you might be left with another kind of problem. The standing water may have left behind a foul odour in the washing machine. Before you can use it to wash your clothes, you will need to remove the stagnant water smell.
Set your washing machine to a regular wash cycle using hot water.
Start the washing machine and wait until it is full of water.
Measure out 4.5 litres (1 gallon) of undiluted vinegar and add it to the washing machine.
Close the door and let the regular wash cycle complete.
Open the door and wipe out the inside of the washing machine with more neat vinegar on a cloth.
Fill the washing machine with towels and set it to the regular wash cycle again. Remove the towels after the cycle has completed.