TL;DR
A burner orifice is the precision brass fitting with a drilled metering hole that feeds gas to a burner at the exact flow its BTU rating requires, sized in number-drill increments where a few thousandths of an inch change the firing rate. Each fuel needs its own size, since propane runs at higher pressure and carries more energy per cubic foot than natural gas, which is why fuel conversions swap every one of these fittings and the appliance data plate lists both specs.
What it means
A burner orifice is the precision brass fitting with a drilled metering hole that feeds gas to a burner at the exact flow its BTU rating requires, sized in number-drill increments where a few thousandths of an inch change the firing rate. Each fuel needs its own size, since propane runs at higher pressure and carries more energy per cubic foot than natural gas, which is why fuel conversions swap every one of these fittings and the appliance data plate lists both specs. A wrong or worn one produces sooting, yellow flames, overheating, or carbon monoxide. Spiders blocking the tiny opening are a classic cause of a grill or furnace burner that will not light.
Where it sits in the glossary
Burner orifice is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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