Well I am certainly impressed on the quality of the responses. Thank you each. the 10:1 theoretical air-gas flowrate + the additional (50%) volume are memorable guidelines. It was good that the code venting reqrmnts were mentioned - had I not known about that. Very thorough all of you - and...
My first interaction with the forum: Hello out there.
I'm a 25 year career HVAC engineer too old but not too embarrased to ask if anyone knows a general rule of thumb:
What might the combustion air flowrates be for a 80% natural draft or 90+% forced draft boiler or furnace?
Combustion airflow...