Hi I have a reehm 90+ furnace, I was told the fresh air and exaust vent were installed wrong. They currently are a 2" pipe inside a 3" fresh air. I need to raise it about 2' because it is too low to ground and snow plugs it. So would like to vent it right when I move it. At furnace it has 2-2" pipes coming out. Thanks for any help. Moe

I've had a new furnace just installed. The intake and exhaust both go through the exterior wall and are spaced 2" apart.

Use a concentric vent. http://www.htproducts.com/literature/lp-166.pdf

Only one hole and it won't look ugly. Recommended clearances are in the literature. Many manufacturer's make them.

There are other requirements that may need to satisfied like, the distance from a window or another source like a gas dryer vent. The install instructions for the furnace should have these.