I saw this furnace in a basement of a home I inspected. This furnace was located in the unfinished part of the basement. The intake takes air from the basement and the exhaust routes outside like it should. My question is, shouldn’t the intake and exhaust vents both terminate outside? Either way, please explain why. I don’t see them often and don’t remember.
I believe its 50 cubic feet of combustion air for every 1,000 btu , so if thats a 80k btu input furnace you’d need about 500 sq ft with an 8’ ceiling
I know the combustion air is sufficient, I’m referring to the vent terminations. Is it ok that it is taking its intake air from the basement and not from outside? I thought they should be outside together. If it’s ok, then what’s the difference?
Me thinks Dennis answered your question, but lest backup a minute. Only you could answer combustible air requirements and the size of the unfinished basement, but I feel Dennis answered your question.
1: This furnace was located in the unfinished part of the basement.
2: The intake takes air from the basement and the exhaust routes outside like it should.
3: My question is, shouldn’t the intake and exhaust vents both terminate outside?
Dennis reply: I believe its 50 cubic feet of combustion air for every 1,000 btu , so if thats a 80k btu input furnace you’d need about 500 sq ft with an 8’ ceiling.
Yep. Looks good to go.
As to your hypothesis, a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation, “I thought they should be outside together” That would be under certain conditions.
Next time start off the post by posting the type of furnace and energy source. Manufacture, Model and serial numbers help. Why? The manufacture installation instructions moot most everything else.
Hope that helped:-)
This is all explained in the RUUD installation manual for this furnace. Have you reviewed the installation requirements from RUUD?
Thanks so much guys for your input. It helps greatly.
James S. Saunders, CPI
Certified Inspectors of North Carolina LLC.
You’ve got to say, I think that if I keep working at this and want it badly enough I can have it. It’s called perseverance. – Lee Iacocca
I think a refinement of the question would be - Is the heating system more efficient if the intake combustion air is sourced directly from the exterior?
Exactly John Paul, its about efficiency. The basement may hold plenty of air but every cubic foot sucked out is replaced from somewhere else, most likely from the conditioned space above.
Also , outside air is cleaner than what’s being drawn in from that basement helping to prolong the life of the furnace.
Exactly my thought. I was wandering what high efficiency furnace are you guys discussing, since it sucks conditioned air. I’m relatively new in those and I’m easily confused.
If I had paid for a high efficiency furnace, I would want it to function as efficiently as possible.