TL;DR
A T&P relief valve is the brass safety valve threaded into the top or side of a water heater tank that opens automatically if the water reaches 210 degrees Fahrenheit or 150 psi, venting before the tank can rupture. Its discharge must run through an air-gapped tube terminating within about six inches of the floor or to an approved drain, never plugged or reduced.
What it means
A T&P relief valve is the brass safety valve threaded into the top or side of a water heater tank that opens automatically if the water reaches 210 degrees Fahrenheit or 150 psi, venting before the tank can rupture. Its discharge must run through an air-gapped tube terminating within about six inches of the floor or to an approved drain, never plugged or reduced. A valve that weeps occasionally may just be doing its job against thermal expansion, but one that has been capped is the classic setup for a tank explosion.
Where it sits in the glossary
T&P relief valve 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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