TL;DR
A multiport valve is the rotary control mounted on a pool's sand or DE filter that redirects water among six positions — filter, backwash, rinse, waste, recirculate, and closed — with one handle. It is the fitting the owner touches most, and worn internal gaskets show up as water running to waste during normal filtration or pressure that will not hold after backwashing.
What it means
A multiport valve is the rotary control mounted on a pool's sand or DE filter that redirects water among six positions — filter, backwash, rinse, waste, recirculate, and closed — with one handle. It is the fitting the owner touches most, and worn internal gaskets show up as water running to waste during normal filtration or pressure that will not hold after backwashing. Moving the handle only with the pump off is the rule that prevents most of its failures.
Where it sits in the glossary
Multiport 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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