by Hearthman on Mon Sep 06, 2010 11:43 am
JP, sorry for the delay but I've been swamped.
This is an interesting situation because the codes don't really address combustion appliances outside of buildings for the most part. I checked the 2009 IRC and found M140104 Exterior Installations simply calls for appliances to be listed and labeled for outdoor installation. The unit must have good support and level foundation.
G2441.1 requires the unit to be listed to ANSI Z21.56. M2006 is for Pool Heaters (does not mention 'spas') and calls for installation per mfrs instructions (pmi), and that the clearances must not interfere with combustion air, draft hoods, or flue termination relief and it must have 'access'. G2427.2.2. simply states appliances with 'integral vents' should be installed pmi and per sectiion 2427.7, which deals with vent termination clearances for mechanical exhaust venting.
Drawing from my experience as a mfrs. technical rep., I would recommend they sketch the installation as a floor plan and vertical elevation showing all windows and intakes with their corresponding measurements and ask the mfr. to issue a written recommendation on placement. This can then be taken to the Building Dept. where most any AHJ would be happy to sign off on it. I also recommend they review their carbon monoxide alarms and install them on each floor, outside sleeping rooms or replace any more than about 5 yrs old. I recommend unlisted low level CO monitors, such as the CO Experts or NSI 3000 over ANY CO alarm listed to UL 2034 or UL2075 due to lack of low level protection and reliability issues.
JP, let me know if you hear back from this poster as this is a good example of a gap in the codes.
Warmest regards,
Hearthman
Keep the fire in the fireplace.