Venting question

can a furnace duct to a room be modified with a fan to draw freash air in?

i do plumbing and heating an no you cant or i should say your really not gonna want to lol.. what you can do is install a "fan in the can" take 3" dryer vent the aluminum shit and take a make up air fan and run the 3" dryer vent outside.

If you know how to wire shit up then take 14 gauge romex wire and wire in 120 volt then take a T-stat and take the 2 wires an you should be able to wire it to the terminals ( all fresh air intakes have different wirring diagrams) so when the T-stat is calling for heat ot A/C the can will come on. if you never did this type of work might take you a while.. 3 hrs plus and if your a hany guy then less then id say 2 hrs. depending on how you can run the vent.

Good Luck bro

If you have forced air heat, there are two kinds of ducts. Hot air ducts, and cold air returns (which allow air to leave and keep it flowing). Ducts are just things you can go look at from the basement. You can touch them and see where they go and what they must be there for. If you want to modify them to go or do something else, there is ductwork material available at hardware and hvac stores. Otherwise I don't understand your question.

I wouldn't modify any ductwork though. It was probably set up just the way it is for very good reasons, and taking the entire place's floorplan into consideration.