TL;DR
A hydrostatic relief valve is a spring-loaded check valve set into the main drain sump or floor of an in-ground pool that opens when groundwater pressure under the shell exceeds the water pressure above it, letting ground water flow into the pool instead of lifting the structure. It matters most when a pool is drained for replastering in areas with high water tables, where an empty shell can literally float out of the ground.
What it means
A hydrostatic relief valve is a spring-loaded check valve set into the main drain sump or floor of an in-ground pool that opens when groundwater pressure under the shell exceeds the water pressure above it, letting ground water flow into the pool instead of lifting the structure. It matters most when a pool is drained for replastering in areas with high water tables, where an empty shell can literally float out of the ground. Service techs inspect and replace the valve during resurfacing because debris can hold it open and cause a slow, mysterious leak.
Where it sits in the glossary
Hydrostatic 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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