Make up on externally vented furnace?

Hi all,

Quick question - If you have a high efficiency gas furnace with direct pvc vents to the exterior does the unit need any additional make up air from the room its located in?

Need more information Thomas, was it single wall PVC, some have intake air also. how big was the room ? and was it sealed.

Not if it’s obtaining its combustion air from the exterior.

Yes, single wall pvc, the unit was placed in a small space under the stairs with no vents in the wall. It was not a sealed unit.

Is the water heater gas?

The water heater was electric and located in another part of the house, so we don’t have to take that into consideration.

Based on this information the answer would be no

I agree with charlie

Thanks Guys for the help, that was what I assumed but wasn’t sure!