I wouldn't stress about it too much. The furnace that heats your dwelling probably creates a lot more steam than your grow does. No one will think twice about seeing steam rising from a vent on your roof in the winter. The same goes for a clothes dryer or gas water heater. The smell of tasty buds should be of much greater concern.
If you do "fix" the steam, you'll end up with a lot a water that you'll have to deal with.