TL;DR
The liquid line is the smaller, uninsulated copper pipe in a refrigerant circuit that carries warm high-pressure liquid from the outdoor condenser to the metering device at the indoor coil, typically 1/4- to 3/8-inch tubing in homes. Because the refrigerant in it is subcooled rather than cold, it runs bare, and a technician reads its temperature and pressure to calculate subcooling when verifying charge.
What it means
The liquid line is the smaller, uninsulated copper pipe in a refrigerant circuit that carries warm high-pressure liquid from the outdoor condenser to the metering device at the indoor coil, typically 1/4- to 3/8-inch tubing in homes. Because the refrigerant in it is subcooled rather than cold, it runs bare, and a technician reads its temperature and pressure to calculate subcooling when verifying charge. A filter-drier is usually installed in this pipe to trap moisture and debris.
Where it sits in the glossary
Liquid line 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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