TL;DR
An unloader valve is the pressure-regulating valve on a pressure washer pump that diverts water into a bypass loop the instant the trigger gun closes, letting the engine keep running without deadheading the pump. A worn or stuck one announces itself through pressure spikes that kick the gun, surging at the nozzle, or full pressure that never develops.
What it means
An unloader valve is the pressure-regulating valve on a pressure washer pump that diverts water into a bypass loop the instant the trigger gun closes, letting the engine keep running without deadheading the pump. A worn or stuck one announces itself through pressure spikes that kick the gun, surging at the nozzle, or full pressure that never develops. Extended bypass operation also cooks the recirculating water, so operators release the trigger no more than a few minutes or shut the machine down between surfaces.
Where it sits in the glossary
Unloader 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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