TL;DR
Pressure tank drawdown is the volume of water a well's tank actually delivers between the pump's cut-out and cut-in pressures—far less than the tank's nominal size, typically a quarter to a third of it. A 40/60 switch on an 80-gallon tank yields roughly 20 to 25 usable gallons per cycle.
What it means
Pressure tank drawdown is the volume of water a well's tank actually delivers between the pump's cut-out and cut-in pressures—far less than the tank's nominal size, typically a quarter to a third of it. A 40/60 switch on an 80-gallon tank yields roughly 20 to 25 usable gallons per cycle. Installers size drawdown so the pump runs at least a minute per start, protecting the motor, and a shrinking figure signals a failing bladder or lost air charge.
Where it sits in the glossary
Pressure tank drawdown 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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