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Regulations for small boilers

IBS_GuyIBS_Guy Member Posts: 19
NFPA 85 applies to boilers with a fuel input of over 12.5 million BTU/H. What code(s) apply to smaller non-residential units, say  between 1 and 12.5 million gas or oil?

Sorry if I'm in the wrong forum



  • Bob HarperBob Harper Member Posts: 732
    boiler codes

    First check your State building codes. Often, there will be mention of boilers and pressure vessels in numerous places such as under the Mechanical Code, Gas code, and possibly Plumbing Code. Next, your State probably has a Boiler Code but that generally exempts residential boilers from most of not all provisions.

    Now, for example: your municipality is under the 2009 International Residential Code. You look under Ch. 12 for Mechanical Administraiton, Ch.13 for General Mechanical System Requirements, Ch 14 for Heating and Cooling Equipment, Ch 17 for Combustion Air, Ch 18 for Chimneys and Vents, Ch. 20 for Boilers and Water Heaters, Ch 21 for Hydronic Piping, Ch 22 for Special Piping and Storage Systems, Ch 24 for Fuel Gas including section G2452(631) on Boilers, Ch 25 on Plumbing Administration, Ch.26 on General Plumbing Requirements, Ch 27 Plumbing Fixtures, Ch 29 Water Supply and Distribution, Ch 30 Sanitary Drainage, Ch. 34 Electrical General Requirements, Ch 35 Electrical Definitions, Ch 36 Electrical Services, Ch 37 Branch Circuit and Feeder Requirements, Ch, 39 Power and Lighting Distribution, Ch 40 Devices and Luminaires, Ch 41 Appliance Installation.

    Now, some of these references also refer you to other documents such as ASME CSD-1 and NFPA 85 where applicable. For chimneys, see NFPA 211. For Oil burners see NFPA 31.

    Now, your local municipality may have local ordinances that could apply. Your local water board along with the plumbing code will dictate the type of backflow prevention required for your installation. If you live in a restricted development, there may be restrictions on components visible to the exterior not limited to but including vents and chimneys, especially their terminations, setbacks from property lines, clearances from adjacent building intakes, and external oil and gas tanks and regulators. You could pass all inspections on a sidewall vent only to find the HOA doesn't allow it. Some municipalities have local ordinances about CO alarms, fusible links to fuel supplies, high and low fuel pressure safeties, and seismic considerations for examples. Installations at high altitudes could require some special adjustments but those should always be guided by combustion analysis.

    Last but not least are the listed instructions that come with the boiler and all the attending components. Every thingamajig attached to a boiler has instructions, requirements and maintenance instructions and possibly a warranty that all must be met.

    There, that's a brief overview. Does that help? ;-)
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