Ok, I was trying to think of the best way to install a heater core while A) Not using already warm case air, and B) not pushing warm air into the case, so I came up with this idea. Both of my ideas show the heater core on the bottom of the case with a hole in the bottom to draw in cool air, a shroud, 2 and two 120mm fans.
The first picture has two 90 degree PVC elbows employed to duct the warm air from the heater core immeadiatly out of the case. I am a little warry about this because I also want to install a window and I only have a Mid-tower from In-Win. A variation on the first would be to run both fans into one 4" outlet, would that be ok?
The second picture shows a duct after the fans to guide the air into a 'chimney' and out the top of the case. This will clean up the side of the case a lot but also be more difficult to duct the 120s into a 3-4" PVC or metal duct. I thought that since warm air rises this might be more effective? Also it would be possible for another fan on the top of the blowhole to suck the warm air out of the tube. I do not think that would be necessary since there is already two 120s blowing out and up. Thoughts?
I was also wondering if two 120s would be needed on the heater core I am going to use, an 89 nissan sentra, the 'fin' area is 8 1/4"L X 5 1/2" H just slightly shorter than two 120mm fans. Good idea for two, or is one enough?
I posted this in the [H] and didn't get any good responses, maybe the PROs can help me out.