High Efficiency Gas Furnace Fresh Air Intake
In these types of furnaces the exhaust is vented outside via a pvc pipe.
High efficiency gas furnace fresh air intake. The exhaust gas of the furnace will not reach over 140 degrees fahrenheit. 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. Since high efficiency furnaces draw air directly from outside the furnace itself does not require a fresh air intake in order to replace inside air that otherwise would have been drawn from the room the furnace is located in. High efficiency pvc or cpvc venting materials and a zero clearance to combustibles.
However this does not mean that your home does not need a fresh air intake just because you have a high efficiency furnace. If a furnace has an afue rating of 90 percent or greater it is considered condensing. See reference 5 in sealed combustion units as most high efficiency furnaces are. When a home is well air sealed or tight it may warrant an optional fresh air intake that pulls air from outdoors into the furnace and prevents partial vacuum situations.