I have pella wood windows crank out type, they are only 9 yr old. they get moisture around bottom,in winter ice, and they get mold or dark buildup in this area how or can this problem be fixed?
Put in a Warranty Claim, they aren't performing and are patently defective. Sorry but, that kind of "performance" over just 9-years is absolutely pitiful. Having any measureable amount of condensation (cause of early wood rot & staining or mold growth) means they AREN'T insulated.
The only other culprit would be DEFECTIVE gaskets. Pella should be quick to respond and should be ashamed of such truly horrible windows. Don't clean nor bleach them and get high quality clear and close-up pictures to Pella right away. This shouldn't be happening, even to the cheapest of windows, so don't take no for an answer and get a lawyer, if needed.