TL;DR
A secondary drain pan is the shallow corrosion-resistant tray installed under a horizontal air handler or evaporator coil in an attic or above a ceiling, sized to catch condensate if the primary drain clogs. The IRC requires it wherever coil leakage would damage building components, with its own drain to a conspicuous point or a float switch that shuts the system down.
What it means
A secondary drain pan is the shallow corrosion-resistant tray installed under a horizontal air handler or evaporator coil in an attic or above a ceiling, sized to catch condensate if the primary drain clogs. The IRC requires it wherever coil leakage would damage building components, with its own drain to a conspicuous point or a float switch that shuts the system down. Water dripping from that telltale pipe over a window or eave is the early warning that the primary line is blocked.
Where it sits in the glossary
Secondary drain pan 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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