What are the clearances to combustibles when using N-Vent? Clearances vary. Please see the installation manual for your unit for more information. Updated on April 14, 2021 Tagged: ClearanceN-vent Was this article helpful? Yes No Related Articles What do I use to run the drip line for the condensation T? Hot Water Supply Capacity How to Install an External Remote What are the clearances to combustible and non-combustible material from the heater? Can I install my heater in a closet/cabinet? Why are the side clearances larger for the new stainless steel models?