Cleaning a man's suit can be a complicated task, especially if mold is involved. Sometimes it is possible to clean mold off yourself to avoid a dry cleaning bill.
Wool comes in a number of different types. If the fabric is made from a tightly knit wool it has the best chance of surviving a washing without shrinkage. The looser the knit, the more likely the shrinkage.
The sooner you can remove a stain the better. The longer it has had a chance to set in, the harder it will be to remove.
Try to first remove the mold, by gently brushing it off with a stiff brush or broom. Newly set in mold should come off in this manner.
Washing a wool suit usually ruins the fabric, however, spot treatment may work if the spot is small enough. Use a mixture of lemon juice and salt to try to remove the stain. Remember to only put the mixture on the stain itself.
Attempting to wash a wool suit may result in shrinkage and wrinkles that are impossible to remove. If the brushing and lemon juice mixture does not work, take the item to a dry cleaner. The dry cleaning bill will be cheaper than a new suit.