High efficiency pvc or cpvc venting materials and a zero clearance to combustibles.
High efficiency gas furnace fresh air intake.
However this does not mean that your home does not need a fresh air intake just because you have a high efficiency furnace.
Fresh air intake for high efficiency furnaces i am a homeowner in new jersey who recently had a carrier infinity ics modulating gas furnace model 58mvc installed.
See reference 5 in sealed combustion units as most high efficiency furnaces are.
The exhaust gas of the furnace will not reach over 140 degrees fahrenheit.
The concentric vent kits are normally used on fireplaces or other mid to standard efficiency direct vent appliances mnc123 jan 4 14 at 6 46.
In these types of furnaces the exhaust is vented outside via a pvc pipe.
Unfortunately the fresh air intake you have described is the second type and does not provide direct combustion air to the furnace room as it is directly connected to the return air plenum for.
If a furnace has an afue rating of 90 percent or greater it is considered condensing.