TL;DR
A reversing valve is the four-way refrigerant valve that lets a heat pump switch between heating and cooling by redirecting compressor discharge to either the indoor or outdoor coil. A small solenoid pilots the slide, and the loud whoosh during defrost cycles is the valve doing its job.
What it means
A reversing valve is the four-way refrigerant valve that lets a heat pump switch between heating and cooling by redirecting compressor discharge to either the indoor or outdoor coil. A small solenoid pilots the slide, and the loud whoosh during defrost cycles is the valve doing its job. When the slide sticks mid-travel or the solenoid fails, the system blows the wrong temperature or loses capacity in both modes—a repair distinctive to heat pumps, since air conditioners have no such part.
Where it sits in the glossary
Reversing 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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