TL;DR
A spillage test is the check for combustion gases escaping a draft hood or barometric damper into the room instead of rising up the flue, performed by holding a smoke pencil, mirror, or match at the hood's relief opening after the appliance has run several minutes. Technicians run it with the house depressurized worst-case, exhaust fans on and doors closed, since that is when water heaters and furnaces backdraft.
What it means
A spillage test is the check for combustion gases escaping a draft hood or barometric damper into the room instead of rising up the flue, performed by holding a smoke pencil, mirror, or match at the hood's relief opening after the appliance has run several minutes. Technicians run it with the house depressurized worst-case, exhaust fans on and doors closed, since that is when water heaters and furnaces backdraft. Persistent spilling indicates a blocked, undersized, or competing flue and is a carbon monoxide red flag.
Where it sits in the glossary
Spillage test 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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