TL;DR
Type L vent is double-wall metal venting with a stainless steel inner liner, listed for oil-fired appliances and pellet stoves whose flue gases run hotter and more corrosive than what aluminum-lined Type B gas vent tolerates. The stainless liner shrugs off the acidic condensate oil and pellet combustion produce, and the listing allows higher flue gas temperatures, up to 570 degrees Fahrenheit.
What it means
Type L vent is double-wall metal venting with a stainless steel inner liner, listed for oil-fired appliances and pellet stoves whose flue gases run hotter and more corrosive than what aluminum-lined Type B gas vent tolerates. The stainless liner shrugs off the acidic condensate oil and pellet combustion produce, and the listing allows higher flue gas temperatures, up to 570 degrees Fahrenheit. Clearances to combustibles and termination heights follow the listing label, and substituting B-vent where L is specified is a fire and corrosion failure waiting to happen.
Where it sits in the glossary
Type L vent 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.
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See also
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