Arkansas HVACR NewsMagazine January 2020

S tate, National, Chapter News Tech News

openings for a room containing combustion appliances:

Vertical opening – One-inch free area for each 4,000 Btu/hr. input of gas burning appliances in the room. Horizontal duct opening – One-inch free area for each 2,000 Btu/hr. input of gas burning appliances in the room. Mechanical fan – One CFM of air for each 2,400 Btu/hr. input of gas burning appliances in the room. Indoor air – 50 cu. ft. of area for each 1,000 Btu/hr. of the appliances. Not to get into the specifics of code because there are lots of specifics that you need to pursue beyond a tip like this, but you must have a dedicated method to get significant air to the furnace to ensure safe and complete combustion. If you do not, the real possibility exists that the furnace could begin burning improperly creating an unsafe condition for the occupants due to Carbon-monoxide. Different parts of the country provide combustion air in different ways, but you MUST have some method of providing unlimited fresh air to a furnace or to the room in which the furnace is located. This means when a furnace is in a tight space, ensure you have some sort of significant combustion air. — Bryan

Bryan Orr ( Founder / Podcaster / Dad of 10 ) Bryan is a lifelong learner, proud technician and advocate for the HVAC/R Trade. This article originally appeared at

https://www.hvacrschool.com/combustion- air/?utm_source=TechTips&utm_campaign=a6ab9c 5c3b- RSS_EMAIL_CAMPAIGN&utm_medium=email&utm _term=0_608fe06f1d-a6ab9c5c3b-64230413