What is the clearance required around a gas furnace in Ohio?

I would like to put up a wall in our basement to separate the unfinished part of the basement from the "living" area. However, the gas furnace would be about 2ft. from the wall (on the side where the pilot lights are visible). I plan to put a 5-ft sliding door in that part of the wall, so that I can access the furnace filter. How much clearance do I need to give the furnace? I live in Warren County, in the greater Cincinnati area.

2008-03-21T17:29:44Z

Additional note: Imagine the room where the furnace is ... approx 20 deep by 12 ft wide. The furnace would be in the corner, approx 2 ft from a concrete wall and 2 ft from the framed-up wall.

Anonymous2008-03-21T05:31:38Z

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the minimum clearances are listed in the furnace literature, and inside most furnaces, but my rule of thumb is leave enough room around the furnace to change it out or work on it without having to tear the wall out, wich is always greater than the minimum clearances

Anonymous2017-01-19T16:20:29Z

Gas Furnace Clearance

James M2008-03-21T11:33:57Z

You cannot put a furnace in an enclosed small room. It will lack combustion air and is against all city codes that I know of, I am speaking of a pilot or 80% furnace. If you look in the installation manual of your furnace Im sure it says on there a minimum size of the installation room and it is about 25 feet by 10 or more. Wall clearance on most furnaces is 2 inches. Do not do it with this type of a furnace as you are describing.

The new 90+ furnaces are sealed combustion with air taken directly from outside and can be enclosed in a small closet.

Kurtis G2008-03-21T07:18:56Z

The minimum clearence is different for different makes and models.
If yours is a zero clearence furnace make sure to refer to the 1st answer. Always think about where you may need to access for maintenance or repairs in the future.
(Zero clearence furnaces ARE safe to install right next to the wall.)

divnlurch2008-03-21T05:43:29Z

check with the local coutny builing codes office or your local DIY center. If it's in a garage or basement I know there is a minimum requirement nationally of 18" off the ground so vapors don't get to the pilot light on gas heaters, for electric kinda the same thing in case of flooding.

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