i've got a goodman 93% furnace.. it vents through a PVC pipe.. the HACK that installed this thing decided the best place to vent was a hole in my wall and right outside my house.. i have a PVC pipe running across my utility room and out the side of my house right next to where i'm puttign my nice paver patio and garden wall.. i was wondering if i could extend the pipe up about another 2 feet and run it through my attic then 90 run the pipe over to my soffit and 90 then a short pipe through the soffit. it would barely peak out the soffit and would look a million time better than what this idiot did.. i assume it needs to run horizional like that for icing problems in the winter? i'd really like some insight here.. if possible my ideal setup would be vent it striaht up out the roof like my plumbing vents.. a less effceint furnace vents striaght up right? any insight?